ESE's works engine tuner

[Frits Overmars]

I really like your idea about outside transfers cooling....After BDC the exhaust port turns into a transfer port :whistle:

[lucf]

The MatLab program is a general computer program that is used for all kinds of physical calculations at technical universities such as TU Delft
When my son studied there, he wrote as an exercise a program in MatLab that was made especially for drag racing. But it can also be used for speed records at Saltlake Utah.
He graduated cum laude in Aerospace cum laude in 2004 and now makes calculations for missiles for his daily work.

All necessary variables can be entered. I was able to test this program directly in practice when in 2000-2004 I did 50cc dragrace on the 1/4 mile in Drachten.
3 distances were measured on the track: in time and speed. It is important that all distances in time and speed are just right in the MatLab output.
In addition to the correct weight and all gears, this can be done by the correct input of torq, cd value, +/- wind in bft, shift time e.o.

For the 18 hp 50cc sprinter in those years, that should happen very precisely. Later I made a lot of calculations with this program, not for Ryger.
Also based on G-measurements I made with MrDyno on the sprinter. Or take over from camera pictures on a racing bike.
Some examples that you can find in this photo album on Facebook https://www.facebook.com/luc.foekema/media_set?set=a.1992436069636.77827.1805454134&type=1

The fact that so many people stick to the results of that test bench, with all the different results, is a mystery to me.
I have seen many test bench results in my life and especially lately with extreme deviations.
A test bench also depends on calculations, which is no different from what happens in the MatLab program.

But I use data recorded on the road under the right conditions and not in a box where the circumstances always deviate.
It seems to me that data measured on the basis of practice is somewhat more reliable.

[TZ350]

After BDC the exhaust port turns into a transfer port :whistle:

Well, yes, Ok that is true in its own way, never thought of it like that myself but I see what you mean, I like it.

[katinas]

Today test - Red rounded piston with matched head/piston, Blue - Std piston tested two days ago.

[Muhr]

Today test - Red rounded piston with matched head/piston, Blue - Std piston tested two days ago.

Have you made any changes to get similar in exhaust duration after you have finished the radius?

[ken seeber]

The thing is the question of variables Luc. For your on-road assessment method (say MatLab), you have so many variables: frontal area (rider position, head up, head down)), road surface over the distance, tyre pressures, rolling resistance, wind, gear change variabilities, temps etc, etc, and in your case an engine that only has to survive for 400 metres rather than a full GP distance, the comparison to other engines under different test conditions is pretty inconclusive.

An inertia dyno, assuming the conditions (temp, humidity and pressure) can be well monitored & corrected for (eg RAD), so there is a minimum of variables compared to an on-road prediction.

For me, I’d like to see a direct, same dyno, A:B:A:B comparison on the same day before drawing any conclusions. However, even with that, when we have to add to that the cooling, mixture, exhaust design and ignition etc might be optimized for a possibly different application, then the numbers almost become meaningless.

The ultimate dyno is who wins on raceday in their particular genre of competition. And irrespective of that, is that we can all learn from each other and, importantly, all have a giggle on the way and not get too serious.

[JanBros]

In addition to the correct weight and all gears, this can be done by the correct input of torq, cd value, +/- wind in bft, shift time e.o.


as according to you dyno's are shite, how have you determinned the correct input of torq ? and if you can determine the correct number of torq before matlab, you can also determine the correct horsepower ... just multiply torq with rpm. so basicly your program is a fancy gimmick that has no real purpose ???

[lucf]

The thing is the question of variables Luc. For your on-road assessment method (say MatLab), you have so many variables: frontal area (rider position, head up, head down)), road surface over the distance, tyre pressures, rolling resistance, wind, gear change variabilities, temps etc, etc, and in your case an engine that only has to survive for 400 metres rather than a full GP distance, the comparison to other engines under different test conditions is pretty inconclusive.

An inertia dyno, assuming the conditions (temp, humidity and pressure) can be well monitored & corrected for (eg RAD), so there is a minimum of variables compared to an on-road prediction.

For me, I’d like to see a direct, same dyno, A:B:A:B comparison on the same day before drawing any conclusions. However, even with that, when we have to add to that the cooling, mixture, exhaust design and ignition etc might be optimized for a possibly different application, then the numbers almost become meaningless.

The ultimate dyno is who wins on raceday in their particular genre of competition. And irrespective of that, is that we can all learn from each other and, importantly, all have a giggle on the way and not get too serious.

Hi Ken, long time ago!
You can merge many variables to one value that you can use, because they all have to do with resistance, in the program I choose a cd value for 1m2.

For my drag racer I was able to determine the correct value as described earlier: 3 measurements of time, speed and distance on the 1/4mile at 60ft - 201 - 402 meters.
If you choose only a little bit wrong in torq or cd, then not one of the 3 matches the real measurements in time and/or speed, made by the organization Explosion.

My little front wheel was not always visible for the time measurement, so I had a very fast 60ft time that nobody understood.
When I shortened the distance of 402m in MatLab with 1.4m of the wheelbase, the starting speed changed from 0 to 14 km/h, everything was right again.
For me a proof that it worked 100% because the backwheel was measured first.
https://www.facebook.com/photo.php?fbid=10204499430844866&set=picfp.1805454134.10204499430604860&type=3&theater

Also measurements for road racing were done with a camera on the rpm or tachometer and you have an extra controle with the switching times and speeds.
So even from a video, the correct Cd value can be separated from the correct torq value.
The best examples are the 50cc speed records on YouTube video with the camera, time and milestones.
You are a little while busy before everything is correct, but you will know if you need it.

For a quick calculation on the 150m I only need weight and time. Because a little change of CD value does not do much anymore.
For my drag racer there were no differences to measure with applying a little streamline or not.
The same counts for correction for wind + of - which can be used in the program, but on short sprints at 150m it will change very little.

And the higher the power and/or the shorter the distance, the less important that CD value and wind becomes.

In the present case, 72cc the Derby, which is not mine, was already tested on the dyno with 31.9 hp at 13.900 rpm
Photo's of the graph are visible on Racehelden forum https://www.deraceheldenvanweleer.nl/index.php?topic=2007.0
Beside it was already written here by Yannik, but most people apparently do not want to see this.

So the outcome with 32.75pk was no surprise to me and especially not when you see how this Sietse and Gerard made it !!

[Frits Overmars]

Today test - Red rounded piston with matched head/piston, Blue - Std piston tested two days ago.
335877 Power graph colours are often hardly distinguishable from one another, but in your graphs red is really red and blue is really blue.
And writing the appropriately coloured comments in the graphs :msn-wink: makes life a lot easier for us viewers. Bravo!

[jellert]

And irrespective of that, is that we can all learn from each other and, importantly, all have a giggle on the way and not get too serious.

Amen to that.

[Jannem]

In the present case, 72cc the Derby, which is not mine, was already tested on the dyno with 31.9 hp at 13.900 rpm
Photo's of the graph are visible on Racehelden forum https://www.deraceheldenvanweleer.nl/index.php?topic=2007.0
Beside it was already written here by Yannik, but most people apparently do not want to see this.



Please. It's not a matter of not wanting to see it. The link you provide requires a login and gives zero information unless you have the login credentials. This has been already mentioned here a few posts back, and it doesn't help your cause to post the same link again with that kind of comment. Just pisses off everyone who's left still actually wanting see information from you.

[katinas]

Have you made any changes to get similar in exhaust duration after you have finished the radius?

No, this last important adjustments not made nor SX65, nor SX85, so exhaust/transfers duration with radiused piston slightly higher than with std piston during all tests.
After looking at all graphs, I really keen to see how engine react to this adjustment and maybe later, he will try to do this with SX65.

[Muhr]

No, this last important adjustments not made nor SX65, nor SX85, so exhaust/transfers duration with radiused piston slightly higher than with std piston during all tests.
After looking at all graphs, I really keen to see how engine react to this adjustment and maybe later, he will try to do this with SX65.

It would be very interesting, if we take 1mm it could be something like 4 ° - 5 ° exaust which would correspond to the difference you have in rpm peak hp.
Geat work:2thumbsup

[wobbly]

I can suggest a way better option to doing MatLab calculations, especially when those results are only logged at a tiny number of discrete points.
There is a app from NT- project called Virtual Dyno.

http://www.ntproject.com/software_vd1eng.htm

This uses all the inputs from the several types of dashboards available that use GPS data to generate a track map.
The data ( from up to 18 satellites concurrently ) is then integrated with the speed/time/mass/inertia info, and produces a Hp curve of the engine thru a whole lap of the track.
My inertia dyno of the best KZ2 engine showed a peak of 48.8Hp at 13800.
The Virtual dyno showed 48.5 Hp at 13600 with an identical curve shape.
My take on the difference is the pipe cooling from 132Km/Hr as every other variable is identical such as egt,water temp,and acceleration rate.
If it wasnt for the hassle/cost of doing track testing, I would ditch the dyno altogether.
As the Virtual Dyno uses a huge number of data points that are averaged to produce a real world representation of the engines performance.

[lucf]

I can suggest a way better option to doing MatLab calculations, especially when those results are only logged at a tiny number of discrete points.
There is a app from NT- project called Virtual Dyno.

http://www.ntproject.com/software_vd1eng.htm

This uses all the inputs from the several types of dashboards available that use GPS data to generate a track map.
The data ( from up to 18 satellites concurrently ) is then integrated with the speed/time/mass/inertia info, and produces a Hp curve of the engine thru a whole lap of the track.
My inertia dyno of the best KZ2 engine showed a peak of 48.8Hp at 13800.
The Virtual dyno showed 48.5 Hp at 13600 with an identical curve shape.
My take on the difference is the pipe cooling from 132Km/Hr as every other variable is identical such as egt,water temp,and acceleration rate.
If it wasnt for the hassle/cost of doing track testing, I would ditch the dyno altogether.
As the Virtual Dyno uses a huge number of data points that are averaged to produce a real world representation of the engines performance.


Thanks for the links Wobb, This will be the new way to measure the power of any vehicle in the future.
And it is done on the road which is much more usefull that any other way.
Your KZ engine has less power on the track than on the dyno, and what do you want to know on the dyno or on the track?

New GPS action camera's from GoPro or Garmin will do the same. With a drone above the circuit you could analyse the power of a F1 car.
The weight is know, the track is known, the weather circumstances are known. So you only have the analyse the G-forces and you can calculate the horsepower.
And if the downforce is known still more accurate.

[jonny quest]

Not trying to make light of your accomplishments LucF.
It's easier for a smaller engine to make more HP per cubic inch than a bigger one. So your percentage is probably off in relation to the RSA.
Smaller bore, better flame travel, less internal friction...

[lucf]

Please. It's not a matter of not wanting to see it. The link you provide requires a login and gives zero information unless you have the login credentials. This has been already mentioned here a few posts back, and it doesn't help your cause to post the same link again with that kind of comment. Just pisses off everyone who's left still actually wanting see information from you.

I never force anyone to have a look.
And there are enough people here who has a login.
And if you don't want to have one, piss of yourself with your useless reply.

[Carel H]

.
Difference = Maximum - Minimum;
if (Difference > 0)
{MAPout = Difference;} // MAPout becomes an indication of air flow through the motor.


}while(IgnPulse != true); // keep looping until there is an ignition pulse.


analogWrite(17, MAPout); // pressure difference as a MAP value sent to the EFI CPU.
int Maximum = 0; // Reset the Maximum Variable so as to find the next crankcase maximum pressure.
int Minimum = 1023; // Reset the Minimum Variable so as to find the next crankcase minimum pressure.
(IgnPulse = false); // reset IgnPulse for the next cycle.
}

With analog sensors there will very often be a numerical difference, so you will be constantly setting Mapout. So there is no edge detection. Edge detection meaning when you want to go from scenario 1 to scenario 2.

Solution 1: make difference larger because of the noise.

Solution 2: use a moving average filter (MAF) to suppress the noise, giving a lower difference (which will be still larger than 0).

And then there is the threshold, which may also be a variable: above this point everything is OK, below this point not. With this, you can have an Arduino based on/off detector, not mapped.

[lucf]

Not trying to make light of your accomplishments LucF.
It's easier for a smaller engine to make more HP per cubic inch than a bigger one. So your percentage is probably off in relation to the RSA.
Smaller bore, better flame travel, less internal friction...

This is corrected in the graphic I showed many years ago for the first time.

https://www.deraceheldenvanweleer.nl/index.php?action=dlattach;topic=1822.0;attach=5929 5;image
https://www.facebook.com/photo.php?fbid=10208986539539779&set=pcb.10208986716384200&type=3&theater

[wobbly]

What I am going to do is datalog the pipe surface temp ( in the header, the mid and in front of the stinger entry ) at the track, as I have done
on the dyno for Neels.
This was done as we wanted to change the EngMod code to enable these real world temps to be input.
Once I know what the real temps are at the track, then I will go back to the dyno with sufficient air blowing over the pipe to simulate the track result.
I can easily do 50 dyno runs in a day, with a change to some variable for every test.
Every result is started and ended with the same water temp with auto cooling control,and egt temps, by changing the jetting.
This is much much easier to do on an inertia engine dyno than trying to get all the other variables lined up, such as tyre temp etc on track.
Its a nightmare in time and money to get sufficient data on track, then have to ignore that run just to change a jet.
But if the time and money constraint wasnt an issue, then I would be at the track every day using just the Virtual dyno app.

[TZ350]

With analog sensors there will very often be a numerical difference, so you will be constantly setting Mapout. So there is no edge detection. Edge detection meaning when you want to go from scenario 1 to scenario 2.

Solution 1: make difference larger because of the noise.

Solution 2: use a moving average filter (MAF) to suppress the noise, giving a lower difference (which will be still larger than 0).

And then there is the threshold, which may also be a variable: above this point everything is OK, below this point not. With this, you can have an Arduino based on/off detector, not mapped.

Thanks for your input, I am enjoying learning a bit about signal processing.

On each cycle (engine revolution) Max cant decrees and Min cant increase, they just go to their respective extremes within each cycle. Then after a trigger pulse is seen they are reset to their respective starting points.

I like your idea of a minimum difference or a moving average, otherwise the difference is the difference between Max & Min with noise.

Mapout is written to the EFI CPU only once a cycle as the cycle is completed. Maybe I could apply a mean moving average to MAPout outside the loop over a number of cycles. Or a moving average to Max and Min within the loop. I will run it in its simple form first with a scope, to see what needs to be done. .... :niceone: thanks for the ideas.

[Jannem]

Nothing pro, but useful entry level tool to make back to back power comparisons on wheels to try things out:

http://atom007.heimat.eu/tmt/gsf_dyno.html

Does have temp and baro corrections though. You can just record the exhaust sound with a cell phone during the run. Beats the guesswork every time. Coupling that with deto and ex.temp sensor is already a lot for a beginner.

[lucf]

This is what Jan wrote when I published the graphic for the first time.

Jan Thiel, tuner of the fastest twostroke ever exist in GP racing till 2007, the Aprilia RSA 125cc, wrote next.

Quote from : Jan Thiel on October 18, 2012 , 06:17:55
Beautiful graphics Luc ! That 'red ' abilities are 100 % definitely achievable. It will , however, most of the time, and especially money, are missing.
To meet the RSA power was used 5 days per week by 6 people and with it the aid of the drawing room, and electronic engineers. And that over about 12 years is not that simple ! We started in 1995 with 46.5 hp, and ended in 2007 with 54hp, so 0.6 to 0.7 HP per year on average. Actually seems very little , but it was a lot of work ! We made about 300-400 cylinders per year. So to get that far, there are at least 3600 cylinders made. But maybe 4800 !, I did not count them .... Of course, a lot of cylinders were equal to each other ! But we surely tested 30 different types of flushing channels, and also exhaust conduit 20 different types. Estimated that another 100 different cylinder heads and of course lots of exhaustpipes!
Overall it was pretty special, and will not arise so quickly again!

Quote from Jan Thiel November 19, 2015
Calculations with a specific program are certainly very useful!
I wish I had something at Aprilia, then I had definitely become further!

https://www.facebook.com/luc.foekema/media_set?set=a.1992436069636.77827.1805454134&type=3
When pictures could be load up directly, I would do so.

[koenich]

thought Jan has actually no idea?

Pity that you keep coming back attempting to collect claps for nothing...:tugger:

[Michael Moore]

It can be more convenient to blow an engine up on the dyno in the shop where you've got all the tools/parts available to fix it vs going to the time/effort of dragging everything out to the track to blow it up.

:)

cheers,
Michael

[katinas]

Interesting, if Mrs. Robert John Tait tried these engines.

https://patents.google.com/patent/EP0337768A2/en

[wobbly]

Yea LucF we have all seen that, from before Jan realized the extent of your inflated views on your ability.
But seems funny that you now have blocked him, as he now throws shit at you at every opportunity.
The whole world is STILL waiting for even a small part of the bullshit you have spouted over many years regarding the Ryger ,to be proven even a little true.
If you are still trying to make it work then even some small insight into the REAL story would help your standing in the 2T community, that currently is well past the U bend in the toilet.

[lucf]

Yea LucF we have all seen that, from before Jan realized the extent of your inflated views on your ability.
But seems funny that you now have blocked him, as he now throws shit at you at every opportunity.
The whole world is STILL waiting for even a small part of the bullshit you have spouted over many years regarding the Ryger ,to be proven even a little true.
If you are still trying to make it work then even some small insight into the REAL story would help your standing in the 2T community, that currently is well past the U bend in the toilet.

Jan is not blocked,

That´s what some people like to tell, who are blocked themselves, because they are not honest.
And such guys I don´t want to see anymore, untill they will speak the real truth.
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131082527#post1131082527

With Jan I´m on speaking terms, we shake hands beginning this year, so no problem with him.

About Ryger, I´m not allowed to tell anything about it. And it´s not my wish that it took so long.

[flyonly]

Does anyone have a contact in Asia for drag bike parts. I am interested in getting some wheels, tires and front forks. I would like to get some advice from a racer. I have tried to FB message some places but get very little response.


Sent from my iPhone using Tapatalk

[philou]

crankshaft balancing for italian tuner


dropping the crankshaft forward as the direction of rotation of the engine tends to favor high rotation speeds, while dropping the shaft in the opposite direction to rotation, such as most of the original series motor shafts from scooters the delivery at low revs is promoted, improving the initial thrust.

Have you noticed that?

[SwePatrick]

Does anyone have a contact in Asia for drag bike parts. I am interested in getting some wheels, tires and front forks. I would like to get some advice from a racer. I have tried to FB message some places but get very little response.


Sent from my iPhone using Tapatalk

I have bought 'thailandtires' from Treatland in USA, very fast deliverys to Sweden.
But the rims i have bought in different places.
I use puch maxi grimeca rim at front, converted to discbrake from a downhill bicycle, easy as i´ve got a downhill fork.
And a Zundapp Star Grimeca at rear.

Front wheel total weight is ~3.5-4kg
Rear is about 4.5-5kg

Total weight of chassi without engine is at this point 37kg =)

[flyonly]

I have bought 'thailandtires' from Treatland in USA, very fast deliverys to Sweden.
But the rims i have bought in different places.
I use puch maxi grimeca rim at front, converted to discbrake from a downhill bicycle, easy as i´ve got a downhill fork.
And a Zundapp Star Grimeca at rear.

Front wheel total weight is ~3.5-4kg
Rear is about 4.5-5kg

Total weight of chassi without engine is at this point 37kg =)

Do you have any pictures?


Sent from my iPhone using Tapatalk

[TZ350]

I have bought 'thailandtires' from Treatland in USA, very fast delivery's to Sweden.

I have brought a few things from TV Treatland over the years, even visited them a couple of times in San Francisco. Great guys, easy to deal with and very prompt shipping.

Go here, then click on the picture to search their on line inventory:- https://www.treatland.tv/

[SwePatrick]

Do you have any pictures?


Sent from my iPhone using Tapatalk

Yes =)

Rear rim is not painted black yet thou.
Both are 17"
Front is 1.2" wide
Rear is 1.6" wide
Front is Vee Rubber Gekko Star 45/90-17
Rear is vee rubber V266 drag slick - 60/75-17

335884335883

[flyonly]

Yes =)

Rear rim is not painted black yet thou.
Both are 17"
Front is 1.2" wide
Rear is 1.6" wide
Front is Vee Rubber Gekko Star 45/90-17
Rear is vee rubber V266 drag slick - 60/75-17

335884335883

They look good. Vee Rubber 266?


Sent from my iPhone using Tapatalk

[Muhr]

https://www.facebook.com/luc.foekema/media_set?set=a.1992436069636.77827.1805454134&type=3
When pictures could be load up directly, I would do so.

Hello Loc
Took a look at your graph of the RSA level / cc and got a feeling that you had taken hk / cc per rev an did this below to confirm. To the question as below, it is thought that transmission losses are 1: 1 with cc?(which I find hard to believe)




RPM RPM/13000(RSA) 51,7 hk/125cc Hk (CC *RPM/RSA*HK cc )

25 cc 22215 1,708846154 0,4136 17,7

50 cc 17638 1,356769231 0,4136 28,1

100 cc 14012 1,077846154 0,4136 44,6

250 cc 10324 0,794153846 0,4136 82,1

400 cc 8819 0,678384615 0,4136 112,2



Sincerely, Muhr

[lucf]

Transmisson losses are in percentage of the power, so are included.

[SwePatrick]

Transmisson losses are in percentage of the power, so are included.


They are not! :no:
But it´s the lazy mans fast explanation(that also comes quite close, but only in the ballpark). :msn-wink:

Losses increases with raised rpm, even if power is the same.
Losses increase with raised torque(power) even if rpm is the same.
Different wide gears chew the oil different.

[SwePatrick]

They look good. Vee Rubber 266?


Sent from my iPhone using Tapatalk

Yes, these ones:

https://www.treatland.tv/v/vspfiles/photos/vee-rubber-V266-65-fslash-75-17in-2.jpg

[Muhr]

Transmisson losses are in percentage of the power, so are included.

Of course my bad.
what i meant was that 50cc at 17600rpm has a transmission loss of 1.1hk sounds a bit short?

[lucf]

Of course my bad.
what i meant was that 50cc at 17600rpm has a transmission loss of 1.1hk sounds a bit short?

I don't care about an exact number for resistance.
The only thing that counts here is the equation.
All is equal in hp/resistance/surface/rpm

[SwePatrick]

All is equal in hp/resistance/surface/rpm.

And thereby your calculations is bull.

[lucf]

And thereby your calculations is bull.

I can't help you don't understand

[wobbly]

And right there Luc we have the crux of all the issues that a huge number of people all around the world seem to have with so much of what you say, in many forums.
Its NOT that we dont understand at all, you narcissistic fuck,its that you are not explaining it at all well ( or in most cases ,not explaining it at all ).

[Muhr]

I don't care about an exact number for resistance.
The only thing that counts here is the equation.
All is equal in hp/resistance/surface/rpm.

It's a way of seeing it. Something else I see, as a possible problem is that after 125cc, you will pretty fast get in to problem with space to achieve enough time area. (you probably need to crush RAS's flow efficiency to achieve the numbers you posted) Or am I wrong?:scratch:

[lucf]

Jan is not blocked,

That´s what some people like to tell, who are blocked themselves, because they are not honest.
And such guys I don´t want to see anymore, untill they will speak the real truth.
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131082527#post1131082527

With Jan I´m on speaking terms, we shake hands beginning this year, so no problem with him.

About Ryger, I´m not allowed to tell anything about it. And it´s not my wish that it took so long.


How about this Wobbly? soon as possible forgotten ?

[wobbly]

Before I answer I will talk to Jan directly.
I am not as friendly and accommodating as he is,so dont get your hopes up just yet.

[SwePatrick]

I can't help you don't understand

I have noticed you live in a theory world.
You simulate this and that in different programs.

I own MOTA myself, and i can see similar things as you when simulating some combo.
If a minor parameter is set wrong the power can raise through the roof easily.
Things aren´t that easy in real world.
The MOTA program doesn´t care about too high compression for example, power raises all the time when adding compression.
If engine is producing 50hp at 15-1 compression, it produces 60hp at 20-1 compression, but it isn´t possible in real world to use that, you´re just fooling yourself.
One need to go into the data check if Bmep etc etc is at acheivable and safe levels.
I get the feeling this is where your ryger gets that power from, that is so jawdropping(as you explained).
Then to make it more trustworthy you take the data and put it in an excelsheet.

If i take my 72hp petrol simulation in MOTA and just change it to methanol, the power raise up above 100hp.
Way off what´s possible in the real world.
More likely the power would be 82-84hp if everything works as it should.

This is just an example of how easy one can mess up simulations if one do not have the sense of what´s happening in the real world.
And as you don´t care about drivetrainlosses tells me you aren´t serious, and thereby you simulations is bull(shit), nothing to spend time on.

[lucf]

I have noticed you live in a theory world.
You simulate this and that in different programs.

I own MOTA myself, and i can see similar things as you when simulating some combo.
If a minor parameter is set wrong the power can raise through the roof easily.
Things aren´t that easy in real world.
The MOTA program doesn´t care about too high compression for example, power raises all the time when adding compression.
If engine is producing 50hp at 15-1 compression, it produces 60hp at 20-1 compression, but it isn´t possible in real world to use that, you´re just fooling yourself.
One need to go into the data check if Bmep etc etc is at acheivable and safe levels.
I get the feeling this is where your ryger gets that power from, that is so jawdropping(as you explained).
Then to make it more trustworthy you take the data and put it in an excelsheet.

If i take my 72hp petrol simulation in MOTA and just change it to methanol, the power raise up above 100hp.
Way off what´s possible in the real world.
More likely the power would be 82-84hp if everything works as it should.

This is just an example of how easy one can mess up simulations if one do not have the sense of what´s happening in the real world.
And as you don´t care about drivetrainlosses tells me you aren´t serious, and thereby you simulations is bull(shit), nothing to spend time on.


In 1968 I was with my private Kreidler 5 speed in the headgroup of the 50cc Dutch TT Assen as fast as:
Suzuki 50 cc of Anscheidt - Jamathi of Paul Lodewijks - 12V Kreidlers of Aalt Toersen and Jan de Vries.
https://www.facebook.com/luc.foekema/media_set?set=a.3413567757040.109062.1805454134&type=3

So no practice experience?
And what do you want to learn me about what symulation at all?
I did have many teachers like you, but I think you must be realy stupid to think I need them?

[Gremlin]

This is a valuable thread with many hours of contributions and discussions from around the world.

The moderators will not tolerate this thread descending into personal abuse, so if you have nothing of value to contribute to the topic at hand don't bother posting.

[TZ350]

335890

Luc is number 19, 1968 Assen TT

<iframe width="560" height="315" src="https://www.youtube.com/embed/eqZr1nshrTY" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen=""></iframe>

Short clip, it is worth looking at it just to hear the 50cc engines in full flight.

I would love to hear more technical insights, not just how good Luc see's himself but real mechanical and design details that we can think about and apply to our own tuning and development efforts.

[lucf]

This is a valuable thread with many hours of contributions and discussions from around the world.

The moderators will not tolerate this thread descending into personal abuse, so if you have nothing of value to contribute to the topic at hand don't bother posting.

You are right, Thanks Gremlin !!

[JanBros]

You are right, Thanks Gremlin !!

maar de gigantische blok hout in je eigen oog zie je weer niet ???


translated : just telling Luc in dutch it was also meant for him, but of course he doesn't see it that way. 'cause he is still the best and everybody still loves him :jerry:

[SwePatrick]

I´m not trying to teach =)
I´m just trying to say that digital numbers in a software isn´t to be trusted, certanly when 'operator of the software' doesn´t care about some essential data to get numbers in the ballpark.

One need to back those numbers up with a real life dyno to get peoples attention and respect.

I have also simulated the Aprilia RSW/RSA in MOTA and got about the same powercurve, but it´s lacking a couple of horses, it says 52 crankhorses at peak.
They dynoed it 54 sprocket horses.
But if i try to acheive the same number with altering things from the blueprints the curve freaks out.
And by that i get to the conclusion that different programmes can´t simulate real life.
You can get close, but that´s all.

So, never trust those programs fully.

[Muhr]

I think if people can stick with telling their own experiences and be humble with that other may have different experiences. I think one can avoid many unnecessary discussions.:drinknsin
Lucf I am still very interested in hearing more about your conclusion that rear wheel power is the same per cc and crank revolution regardless of cylinder volume. You have also added a hp to some graphs, which would be interesting to know more about.

[jamathi]

335891
This is a valuable thread with many hours of contributions and discussions from around the world.

The moderators will not tolerate this thread descending into personal abuse, so if you have nothing of value to contribute to the topic at hand don't bother posting.

Maybe this is interesting to some people
A picture of the Ryger piston...
It keeps breaking!
Does anyone understand why? You Wobbly?
Power is less than 40HP, probably around 35, or less.
About 50% less than was announced......
Just about as fast as a much cheaper ROTAX Max
The piston looks quite heavy.
No change of 30.000 rpm!
Maybe half of it?
Anyone still believing in this 'miracle'?
How could anyone ever take this seriously?
The scrap heap is still waiting, patiently.

I also heard some people invested more than 500.000 Euro in this project.
Sadly everything will be lost.....
As not even 1 engine was sold, and there are 50 in stock

There will be NO personal abuse!

[Martin1981]

I have the feeling that the ryger engine is shit. But the piston looks funny.

[jamathi]

I have the feeling that the ryger engine is shit. But the piston looks funny.

Yes, the piston makes you laugh.....
But your feeling is 100% right.
Shit

[Muhr]

335891

The piston looks quite heavy.
No change of 30.000 rpm!
Maybe half of it?

There will be NO personal abuse!

wondering what bigend force would be at 30000 rpm 8-10,000 kg?

[lucf]

This is an article about Ryger in an Italian magazine.
Nobody in the Ryger team knows that it would be published.
Frits has not put in any to this Ryger concept in the few month he was involved.
I translated the Italian text via Google because I wanted to know what was being written.
The translation is therefore not perfect, but the scope is clear.

Especially the photo caption below makes clear what your dear gentleman Frits told the Italians.

Ryger 125 Revo:
Revolutionary and devastating or not?
Among the new homology questions for the 125 KZ-class, there is a new Dutch engine that would have 70 hp and would reach 30,000 rpm. But was it so? And what effect would his arrival on the market and in the race have?
While the eyes of all kartists who were interested in the new techniques were mainly focused on the new single-engine "ok" engines that debut in 2016, it seems that the revolution is coming from another direction.
Among the requests for homologation for the 125-class with the gearbox, one in fact came from the Netherlands, whose miracles were discussed. Let's talk about the engine Ryger 125 revo, a unit intended for KZ which, according to the few technical information available, would have the beauty of 70 horses and would reach 30,000 rpm. It is at least revolutionary, and not just from a technical point of view, if this news were confirmed, the effects on the market and on the offers could be devastating. But they can also all be useless concerns.

Between accusations and rumors The question is therefore parracchie ...... However, assuming that there is little else outside the certain numbers on Facebook. It is not our custom to talk on the basis of simple actions, but it is clear that such news can not pass in silence, if only because of the consequences that could be a hoax, an exaggeration of widespread art to talk about before I even saw something "black on white"?
A hypothesis anything but peregrine falcon in an environment such as that of karting that lives a lot on the paddock voices.
and an opportunity to consider is answered by Andrea Severi (SGM) who reasons the issue in such terms - that these figures are scattered to speak only. Anchio I only heard about it, but there are many things that come back mon. For example, we talk about solutions for patents, but is this really true? Because in that case there would be official documentation, my environment I did not find anything. But if the method really works, it would be something epochal in the world of motorsport. And the first thing I would do, even before the speech with my neighbor would be to patent everything.
In short, the fact of accepting the veridicity of certain statements and a first step is not of poci. Also because the first question that arises and how we would come to a result after years and years of development of the twofold technique and without any results so far not even comparable?

photo caption
The Dutch Ryger 125 revo is derived from an idea that has been developed by Frits Overmars for about ten years, the primose that can be seen on the photo



https://www.deraceheldenvanweleer.nl/index.php?action=dlattach;topic=1822.0;attach=5945 0;image

Isn't it a bit the same like "his FOS" ?

[JanBros]

Luc, go fight your personal war somewhere else.
you contribute absolutly nothing to tis topic but trashtalk. I vote for a ban.

[Martin1981]

http://fs1.directupload.net/images/180328/temp/i6uushl9.jpg (http://www.directupload.net/file/d/5040/i6uushl9_jpg.htm)


lucs last post proves nothing. as usual....

there is one thing i do not understand. Frits said that he drove a kart with a ryger prototype engine. he told us that he was amazed by it and it was a rocketship. was he forced to lie because he was misused as a marketing tool by the ryger guys? i dont believe that Frits lies to us.

so we must assume that there was one working prototype at least.

now we only get information of rygers with estimated poor 35 hp AND bad relability.....

WHERE IS THIS WORKING PROTOTYPE LUC? even if it is not reliable.... if it has the power Frits felt, then put it on a kart track, invite all the karting VIPs and experts and show its power! even if it will only last a single lap and then blows up.... even if it would only last 2 straights and 3 corners.... one would see and hear if the engine is strong. Why dont the ryger guys do that? where is the fucking problem?

i can explain myself or at least understand the poor reliability because of the short rod and the force it puts on the piston shaft and so on. but i cant understand the poor 35 hp because Frits impression sounds like way more than 35.

[ken seeber]

The question was asked of Frits at the time as to the subjective acceleration and he made the point that it felt very, very good. However how well calibrated was Frits on the day? I reckon that if anyone got into a KZ kart and went for it up some dodgy and skinny road between tulip farms, they would have to have a grin on their faces. Subsequent to that, Frits wouldn’t answer a multitude of questions and later that year, got himself clear of the project.

What he actually drove (was it a Ryger or some 175 cc KZ?) is one question and I think that Frits, from his posts, didn’t actually witness any 70 hp and 30,000 rpm testing. And wouldn’t any of us hang around if we actually saw a true, calibrated 70 hp, rather than the 55 hp or so of the best KZ.

None of us have any idea of the extent of Luc’s involvement and what he has seen.

Fundamentlly we don’t want to lose ESE or see it distracted. I therefore agree with Gremlin, however we need to go further. It should be that no-one presents anything that can’t be reasonably demonstrated and or proven. Wouldn’t want this to interfere with ideas, questions and answers, knowledge sharing, the odd bit of lighhearted banter and the rest of the usual stuff that goes on. But if you get a result and make a claim, then be able to demonstrate it with credible test results (A-B-A) or with race wins, or with something that we can all understand and believe. I think we all see ESE as a forum of sharing information to facilitate the 2 stroke to go forward into the future, in various applications. Maybe the best forum in the world.

We all get so much misleading formal media and social media bullshit these days, eg Cambridge Analytica, that we don’t know what to believe, so the best we as individuals can, at least, do is to strive to counter this with integrity and meaningful & relevant facts.

There’s no individual heroes here, but just a lot of clever guys willing to share their hard won knowledge and experiences for the cause.

[SwePatrick]

If i remember correctly there was quite a short rod in the ryger, yes?

And even if the 'guide' for the piston in that blockadapterplate(or what to call it) helps piston from rocking.
It will be HUGE sideloads on this guide where the rod connects to it.
Certanly when trying to rev 30k with a short rod.
The engine would probably never produce power due to hard high frequency vibrations that are foaming fuel etc etc.
And the special pistons need to be made of steel to take the abuse from the rod

To rev high, one need a stroke rod ratio that allows it, even if it´s hidden underneeth a fancy blockadaptorplate =)

[SwePatrick]

wondering what bigend force would be at 30000 rpm 8-10,000 kg?

And the sideforces on the wristpin as i mentioned above.

[laihialainen]

Hello.

Does somebody know, what is the compression height of ktm 50 sx piston? From piston pin center to top corner? Does model year have any effect?

I tried to google but didn't find. Thanks.

[shnaggs]

Maybe a very stupid question, but all this talk about the Ryger and its short con-rod and side loading blah blah blah. How is this any different than say a 250cc 4T single, they have stupid short con-rod's and rev just as high if not higher??? So how would this be any different in the Ryger application?

[Muhr]

Hello.

Does somebody know, what is the compression height of ktm 50 sx piston? From piston pin center to top corner? Does model year have any effect?

I tried to google but didn't find. Thanks.
21,5mm fairly new one.

Maybe a very stupid question, but all this talk about the Ryger and its short con-rod and side loading blah blah blah. How is this any different than say a 250cc 4T single, they have stupid short con-rod's and rev just as high if not higher??? So how would this be any different in the Ryger application?

Discussion was about 30,000 rpm. And I think new racing 4 stroke engines use a lot of cylinder offset.(I am a 4 stroke amateur):D

[SwePatrick]

Maybe a very stupid question, but all this talk about the Ryger and its short con-rod and side loading blah blah blah. How is this any different than say a 250cc 4T single, they have stupid short con-rod's and rev just as high if not higher??? So how would this be any different in the Ryger application?

They also spit the rod on the ground quite more often :(

kx450 on video just as an example
https://www.youtube.com/watch?v=iYXeEIyp1fc

KX450 rod = 101mm stroke 62.1 gives rod ratio of 1.62
KX250 rod = 125mm stroke 72mm gives rod ratio of 1.73

Me personally i have never heard of a KX250(2t) spitting a rod, but ofcourse it has happened.

But i actually think that they keep the rods short in foulstrokes to keep engines from building height due to everything that is needed to make a foulstroke to run is in the head and it build high center of gravity and it also interferes with framedesign etc etc.

[jellert]

The question was asked of Frits at the time as to the subjective acceleration and he made the point that it felt very, very good. However how well calibrated was Frits on the day? I reckon that if anyone got into a KZ kart and went for it up some dodgy and skinny road between tulip farms, they would have to have a grin on their faces. Subsequent to that, Frits wouldn’t answer a multitude of questions and later that year, got himself clear of the project.

What he actually drove (was it a Ryger or some 175 cc KZ?) is one question and I think that Frits, from his posts, didn’t actually witness any 70 hp and 30,000 rpm testing. And wouldn’t any of us hang around if we actually saw a true, calibrated 70 hp, rather than the 55 hp or so of the best KZ.

None of us have any idea of the extent of Luc’s involvement and what he has seen.

Fundamentlly we don’t want to lose ESE or see it distracted. I therefore agree with Gremlin, however we need to go further. It should be that no-one presents anything that can’t be reasonably demonstrated and or proven. Wouldn’t want this to interfere with ideas, questions and answers, knowledge sharing, the odd bit of lighhearted banter and the rest of the usual stuff that goes on. But if you get a result and make a claim, then be able to demonstrate it with credible test results (A-B-A) or with race wins, or with something that we can all understand and believe. I think we all see ESE as a forum of sharing information to facilitate the 2 stroke to go forward into the future, in various applications. Maybe the best forum in the world.

We all get so much misleading formal media and social media bullshit these days, eg Cambridge Analytica, that we don’t know what to believe, so the best we as individuals can, at least, do is to strive to counter this with integrity and meaningful & relevant facts.

There’s no individual heroes here, but just a lot of clever guys willing to share their hard won knowledge and experiences for the cause.

Very well said, just what I was thinking. Getting back into a kart even after a short winter break can make anything seem impressive. So like you say no matter how much power it actually was (even if it was only 35-40hp), it would likely make you smile.

I think people should be able to come show their achievements without necessarily having hard proof, provided they don't come fishing for compliments and they share their experience for fun or to share knowledge. If they make claims that people find hard to believe, then yes they should definitely be able to back them up with hard data. Finding old quotes from highly respected people in the industry and trying to smear them is definitely not a good way to back up your claims :shifty:.

[Martin1981]

The question was asked of Frits at the time as to the subjective acceleration and he made the point that it felt very, very good. However how well calibrated was Frits on the day? I reckon that if anyone got into a KZ kart and went for it up some dodgy and skinny road between tulip farms, they would have to have a grin on their faces.


i wonder if Frits will confirm that he might be wrong and that kart only FELT fast.

so maybe Frits should be re calibrated? wobbly, do you have the equipment to do that? :laugh: i am only joking of course. please dont feel offended, Frits.

[Frits Overmars]

This is an article about Ryger in an Italian magazine.
Nobody in the Ryger team knows that it would be published.
Frits has not put in any to this Ryger concept in the few month he was involved.
I translated the Italian text via Google because I wanted to know what was being written.
The translation is therefore not perfect, but the scope is clear.
Especially the photo caption below makes clear what your dear gentleman Frits told the Italians.
....................
photo caption
The Dutch Ryger 125 revo is derived from an idea that has been developed by Frits Overmars for about ten years, the primose that can be seen on the photoI never had any contact with the author of this article, but apparently he deemed it useful to attach my name to it anyway.
I never claimed that the Ryger was derived from my ideas. But Luc jumps to the opportunity of calling me a liar. If this isn't personal abuse, what is?

[Jannem]

And right there Luc we have the crux of all the issues that a huge number of people all around the world seem to have with so much of what you say, in many forums.
Its NOT that we dont understand at all, you narcissistic fuck,its that you are not explaining it at all well ( or in most cases ,not explaining it at all ).

While this is not ”nicely” expressed and diagnosis is against Goldwater rule, it’s hard to disagree if you have any personal past exposure to the disorder in question.
There’s only one way to stop the repetitive vicious circle a single “contributor” so successfully creates to gain the dose of attention and controversy.
If Ryger or any other Luc’s achievements will eventually shake the world, I’m sure all the hard information will be available elsewhere for everyone to swallow their disbelieves. Which, I believe many will happily do, if that’s the way it goes.

I don’t know if I will be banned for saying this. If that’s the way it goes, I respectfully thank everyone for the fantastic discussion and information shared.

Ban the Fucker. He repeatedly pulls the thread to the pool of shit.

[Flettner]

jannem, I like your style, go for it.

[teriks]

I never had any contact with the author of this article, but apparently he deemed it useful to attach my name to it anyway.
I never claimed that the Ryger was derived from my ideas. But Luc jumps to the opportunity of calling me a liar. If this isn't personal abuse, what is?
For quite some time I was under the impression that much of the controversy's from lucf might have been due to a language barrier, but no more.

[Carel H]

While this is not ”nicely” expressed and diagnosis is against Goldwater rule, it’s hard to disagree if you have any personal past exposure to the disorder in question.
Ban the Fucker. He repeatedly pulls the thread to the pool of shit.

The Goldwater rule is not applicable, Luc not being a public figure. So the perception of narcissism is tolerable.

One can go down to "whataboutism", the reflex when asked a question to instantly point a finger to someone else.

The result is a now constant obstruction of a knowledge and ideas sharing thread, with mutual respect from the participitants, one finds rarely on the worldwide web. This countryman of mine, Luc Foekema, aka LucF, has a revenge mission to destroy everything he sets his eye on, to get his right, however wrong it may be. And he gets his attention, mostly negative, which seems to thrive him most. He may know some things, but it conflicts with his secretiveness.

He reads the moderator warning, put there for his behaviour, acknowledges it fully and goes on after that in his usual derailing way. Enough is enough.

BAN HIM NOW!

[WilDun]

Yes, I reckon ban him! I told him what he was doing to the thread (twice), he agreed and waited a week or so, then pressed the reset button and started all over again!

OK you guys, time to get back to work and report back on your pathetic (but enjoyable) efforts with your pathetic conventional machines!

........ and I'm always right!! :laugh:

[koenich]

A picture of the Ryger piston...
It keeps breaking!
achieving the concentricity for the single parts and make them line up properly in an assembly is already quite a challenge.


I also heard some people invested more than 500.000 Euro in this project.
Sadly everything will be lost.....!
At one point Tim Schrick (son of famous Nockenwellen Schrick) was also involved creating his own Ryger Facebook page and stuff. Big suprise he pulled out too...


Luc, go fight your personal war somewhere else.
you contribute absolutly nothing to tis topic but trashtalk. I vote for a ban.
+1 for ban. Everytime Mr. Inventor shows up with new bogus screenshots or graphs this whole thread derails to the quality of Lucs claims.


Maybe a very stupid question, but all this talk about the Ryger and its short con-rod and side loading blah blah blah. How is this any different than say a 250cc 4T single, they have stupid short con-rod's and rev just as high if not higher??? So how would this be any different in the Ryger application?
what helps IMO, there are no ports in the cylinder walls disturbing lubrication and giving the piston the possibility to rock into plus they are better lubricated.

As SwePatrick already pointed out KTM especially advertises that they shortened the conrod on their SXF250 to minimize packaging.

[Grumph]

what helps IMO, there are no ports in the cylinder walls disturbing lubrication and giving the piston the possibility to rock into plus they are better lubricated.


Modern 4T pistons are absurdly short and the life is generally limited by bore clearance getting too large - which lets them rock and destroy the skirts...
But the extra coasting stroke does wonders for piston cooling.

Looking at the calls to ban Luc is interesting. I have no opinion either way - that's what the ignore function is for IMO.
Most of you don't look at the rest of this site. We have at least two locals on here who should be banned before Luc - just on the number of occasions they've derailed threads/started arguments/provoked rage/given false or dangerous advice...But management appears to be reluctant to ban anyone.
It's their call after all.

[F5 Dave]

This isn't Salem. You shouldn't Burn him.

. . . Oh wait. Sorry I misread that. As you were.

[gav]

Looking at the calls to ban Luc is interesting. I have no opinion either way - that's what the ignore function is for IMO.
Most of you don't look at the rest of this site. We have at least two locals on here who should be banned before Luc - just on the number of occasions they've derailed threads/started arguments/provoked rage/given false or dangerous advice...But management appears to be reluctant to ban anyone.
It's their call after all.

The tribe has spoken and he's been removed off this island ....
He's goneburger :devil2:

[Jannem]

Looking at the calls to ban Luc is interesting. I have no opinion either way - that's what the ignore function is for IMO.
Most of you don't look at the rest of this site. We have at least two locals on here who should be banned before Luc - just on the number of occasions they've derailed threads/started arguments/provoked rage/given false or dangerous advice...But management appears to be reluctant to ban anyone.
It's their call after all.

Fair comment.

Ignore works reasonably if it’s widely used, so less members will join the controversy. However, those who anticipate being targeted personally in public forum can’t use it to be able to defend themselves from claims they see unjustified and harmful.

When you have one source for all this above others, I think it’s reasonable to ask for a ban, which I have done.

Whether it’ll be taken seriously remains to be seen, but I will adopt the ignore function anyway to save myself from the stuff I don’t care about, even if it won’t quell the pages long aftermaths of these appearances.

[mattology]

this is my first post, but i'm a long time reader, and i just wanted to say that i do not think lucf contributed anything at all but conflict to this thread.

thank you for providing incredible reading material. my little two strokes thank you as well.

[JanBros]

Looking at the calls to ban Luc is interesting. I have no opinion either way - that's what the ignore function is for IMO.
Most of you don't look at the rest of this site. We have at least two locals on here who should be banned before Luc - just on the number of occasions they've derailed threads/started arguments/provoked rage/given false or dangerous advice...But management appears to be reluctant to ban anyone.
It's their call after all.

let's say this was a track-days topic where people talk about the do's and the don'ts, where people talk about setting up your track-bike, suspension, etc...
in fact it is THE HOT TOPIC worldwide, because even Casey Stoner and Troy Bayliss are long time posters who share all their knowledge and answer almost any question you throw at them. Now every now and then Anthony Gobert (drunk or not, we will never know :drinkup::innocent:) comes in and throws an angry post in the middle about how Troy was very sneaky in the 2000 Phillip Island race and even blatantly lied about it and still will not say he was in the wrong that day. He never posts anything else, he never gives info on riding/bike set-up/...
After a number of occassions like this, Troy almost has enough and says he will stop posting if this continues. Casey feels the same and agrees with Troy to make a statemant.

now we can all ignore Gobby's posts, but that will not help Troy. Troy leaves and as a consequence Casey also leaves. Gobert "won" and we all lose. Does anybody want that ? Does it it make a difference if Gobert would be banned ? would anybody feel he loses something if Anthony was banned from posting his "gossip" ?
Does it matter to us if Frits or Luc was first with that new scavenging system ? No. at least Frits talks about it and shares his thoughts about it. Luc only came to look for someone to help him so he can run away with the credits should the system ever work nicely.

My choice is clear, as should everybody else's. Luc is a troll and nobody want's a troll next to them interfering with pointless gibberish during the conversation in their favourite pub.

[koenich]

https://youtu.be/r2tzB-WarX0
yet again :brick: what is this video supposed to show? that you are able to mount a gopro (judging by the quality like first gen one) to a kart?

can't be a ryger engine? no 30.000 1/min, not crazy fast...about the laptime of a Rotax Max (https://www.youtube.com/watch?v=OKh_hRzQy4w).

let me guess, we need to be patient :facepalm: just f*** off...

[TZ350]

Unless Luc himself deleted them it looks like the "Mod's" have removed his last post or two and maybe blocked him. I myself won't miss a cook who endlessly tells you how good he is without ever laying anything on the table for all of us to enjoy.

Luc could have been an interesting contributor but just did not seem to grasp that this thread is like a happy dinner party. Where you only have to enjoy other peoples company and efforts and bring something for the table if you can. However humble the offering, it all adds to the occasion.

[husaberg]

Unless Luc himself deleted them it looks like the "Mod's" have removed his last post or two and maybe blocked him. I myself won't miss a cook who endlessly tells you how good he is without ever laying anything on the table for all of us to enjoy.

Luc could have been an interesting contributor but just did not seem to grasp that this thread is like a dinner party. Where you only have to enjoy other peoples company and efforts and bring something for the table if you can. However humble the offering, it all adds to the occasion.
It is a shame I am sure if he could put his ego aside I am sure he could have contributed something useful but LucF was bined for repeated abuse of forum members and attempting to derail a fine technical thread by repeated trolling of other members.
If he attempt to return under a new pseudonym he will be binned again.
KB is lucky to have overseas legends such as Jan Thiel and Frits Overmars posting as well as other occasional posters such as Francis Payart and Neels van Niekerk.

[TZ350]

GIBs installed, throttle belt lay out, bottom pulley will be on an eccentric bearing housing for system tension, top pulley will have the TPS and cable drive quadrant (throttle cable). left hand pulley is 10T , right hand pulley is 12T, I want one to open a little more than the other.

Very Clever.

But you need to go to the original post to see the pictures, this is a very interesting project. Throttling the inlet and changing the inlet timing by opening/closing the aperture on the rotary valve cover.

[Flettner]

-----------

[F5 Dave]

I remember Greenie telling me that getting some help from Wob showed him how little he knew. I thought; yeah sure. But this thread sure showed me how little I knew. Pity it came too late in my racing career.

[katinas]

........what is?

The spirit of Rashleigh was flying through, after 200 years, from Sir Walter Scott novel.

[SwePatrick]

I have been simulating for hours for my friends 98cc minarelliengine.

One thing that amases me is section 2 on this printout.
Everytime i add a 'square' piece in the header it gives me a boost in power.
And almost everytime it raises the whole curve(and previous projects have shown the same in real life dyno)

By adding this i can run harder tapering on section 1 and 3 to acheive the same 'medium' tapering as a long header that replaces 1.2.3 sections would have to meet cylinder and section 4.

Anybody noticed the same?

Rgds


335919

[katinas]

-----------
Thanks, very nice.
Interesting, how flow restrictions, at partly opened black parts, influence engine performace before full throttle.
Maybe, would be some difficulties with jetting at partly opened throttle ( if not with EFI )

[Muhr]

-----------

Love it! The thoughts run away to what you can do if you can control them individually over rpm

[emess]

-----------

Great! 2T innovation at its very best :clap::clap::clap:

[crbbt]

-----------

I've been wondering lately if that would be enough of a restriction (out of the power band) to be able to run without the inlet disc properly

[TZ350]

I've been wondering lately if that would be enough of a restriction (out of the power band) to be able to run without the inlet disc properly

I think it will still have a conventional rotary valve. The sliding gibs just change the timing and throttle the opening.

[Frits Overmars]

I have been simulating for hours for my friends 98cc minarelliengine.
One thing that amases me is section 2 on this printout.Everytime i add a 'square' piece in the header it gives me a boost in power.
And almost everytime it raises the whole curve(and previous projects have shown the same in real life dyno)
By adding this i can run harder tapering on section 1 and 3 to acheive the same 'medium' tapering as a long header that replaces 1.2.3 sections would have to meet cylinder and section 4.
335919The long header replacing sections 1, 2 and 3 would have 34 mm initial diameter, 48 mm enddiameter, 175 mm length and 4,58° taper, right?
With this taper, the diameter at the end of section 2 would be 41,6 mm. Substituting section 2 with a parallel piece of 38 mm tubing has the effect of locally denting the taper and lowering the Helmholtz frequency.
Without knowing anything about the engine I suspect that the header taper may be too steep and the Helmholtz frequency too high, and it would require a lot of ignition advance to get the frequency of this pipe where you need it. But of course much depends on the chosen exhaust timing and resonance rpm.

[Muhr]

yet again :brick: what is this video supposed to show? that you are able to mount a gopro (judging by the quality like first gen one) to a kart?

can't be a ryger engine? no 30.000 1/min, not crazy fast...about the laptime of a Rotax Max (https://www.youtube.com/watch?v=OKh_hRzQy4w).

let me guess, we need to be patient :facepalm: just f*** off...

0.6 sec slower than a rotax:brick::brick::brick:
http://www.iwt.com.au/images/FR125_09_11.jpg

[SwePatrick]

The long header replacing sections 1, 2 and 3 would have 34 mm initial diameter, 48 mm enddiameter, 175 mm length and 4,58° taper, right?
With this taper, the diameter at the end of section 2 would be 41,6 mm. Substituting section 2 with a parallel piece of 38 mm tubing has the effect of locally denting the taper and lowering the Helmholtz frequency.
Without knowing anything about the engine I suspect that the header taper may be too steep and the Helmholtz frequency too high, and it would require a lot of ignition advance to get the frequency of this pipe where you need it. But of course much depends on the chosen exhaust timing and resonance rpm.


Yes, to be exact 4.574 total degree on the diam.
It´s a dragracing pipe to be used with methanol, and the taper is 2.287 on the radius.
I have tried milder tapering also, but it seems like the cylinder want quite big diameters on 1st and 2nd diffuser.
If i make those two a little bit smaller in diam, i loose power and the powercurve becomes very 'peaky'.
The timings is 134/134/134/196
And it seems happy with 15 degree advance at peak power, this with 10.57-1 i compressionratio and 1.28 in crankhouse compressionratio.

[jonny quest]

Those are some high transfers Swepatrick

[Flettner]

Thanks, very nice.
Interesting, how flow restrictions, at partly opened black parts, influence engine performace before full throttle.
Maybe, would be some difficulties with jetting at partly opened throttle ( if not with EFI )

this one will run TPI mark two. Ulitamatly designed with these Gibs (black things)being controlled by the ECU.
Twist grip just tells the ECU what the rider wants. ECU tells the engine room what to do.
This cable (toothed belt) opperation is just to get the bike up and running.

[jbiplane]

A question

Recently JPX paramotor change exhaust system.
Now it become lighter, quiter...
https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSfsca4FnbK7FOXwFejqRBFoEf5-tA8MxZbF6_78rG1yVQFfhPGKw

Before it was more classical
https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQPlqMoP6e_eEEVdWo5SJoWeGWGCBxU9 rGtesgqNUB0RSB0AoEveQ

Any idea of internals?

[katinas]

this one will run TPI mark two. Ulitamatly designed with these Gibs (black things)being controlled by the ECU.
Twist grip just tells the ECU what the rider wants. ECU tells the engine room what to do.
This cable (toothed belt) opperation is just to get the bike up and running.

Thank you, I need adjust my old thinking.

Add pic of modified crank for testing with one cylinder on NS 250 crankcase.

[SwePatrick]

Those are some high transfers Swepatrick

Yes, i know.
But this isn´t a cruiser ;)

[Frits Overmars]

Yes, to be exact 4.574 total degree on the diam. It´s a dragracing pipe to be used with methanol, and the taper is 2.287 on the radius. I have tried milder tapering also, but it seems like the cylinder want quite big diameters on 1st and 2nd diffuser.
If i make those two a little bit smaller in diam, i loose power and the powercurve becomes very 'peaky'. The timings is 134/134/134/196
And it seems happy with 15 degree advance at peak power, this with 10.57-1 i compressionratio and 1.28 in crankhouse compressionratio.Aha, the methanol may explain the short pipe and the small need for ignition advance because of a low EGT. But since you mentioned a Minarelli base engine, I assumed that an 98 cc version would have a short stroke and a big bore, which would not help blowdown angle.area. The 134° transfer timing won't help either, but it does lower the Helmholtz frequency quite a bit when the crankcase volume is coupled to the cylinder volume at such an early stage in the cycle. So that may explain the preference of the engine for big pipe diameters.

I based my guesswork on an assumed 39,7 mm stroke, 56 mm bore, 130°/198° port timings, 15:1 compression ratio and max.power at 12500 rpm. How far was I off?

[fpayart]

It is a shame I am sure if he could put his ego aside I am sure he could have contributed something useful but LucF was bined for repeated abuse of forum members and attempting to derail a fine technical thread by repeated trolling of other members.
If he attempt to return under a new pseudonym he will be binned again.
KB is lucky to have overseas legends such as Jan Thiel and Frits Overmars posting as well as other occasional posters such as Francis Payart and Neels van Niekerk.

Hello everyone,

Thank you Husaberg for having a thought for me.
Francis PAYART is not very diligent as a contributor to your incredible forum.
By cons, I read regularly and I appreciate a lot of your posts.

Regarding LucF, it's a shame he did not know how to moderate himself, I appreciate his work, I think he still had a lot to share.
This forum is not the place for disputes between people.

For my part, I have a lot of work, especially with a new project of a new complete bike.
We are fortunate in France to still be able to participate in specific races with two-stroke 250cc Grand Prix motorcycles.
Since last year, we participate with two prototypes equipped with Superkart FPE engine.
One from an Aprilia RS250 road chassis and the other from an Aprilia RS125 road chassis.
The experience is encouraging enough that I decide to re-design a new, more compact engine, better suited to the bike.

Some information and pictures:
http://forum.2temps.fr/viewtopic.php?f=8&t=16752
http://forum.2temps.fr/viewtopic.php?f=8&t=17577
http://www.pit-lane.biz/t875p450-technique-fpe-superkart

[TZ350]

Finaly got the Dyno up and running again in its new home.

335926335927335928335929

Ok its not a 2T but I spent a very enjoyable afternoon helping with Mikes impressive #6 Turbo EFI Bucket project.

[TZ350]

Some information and pictures:
http://forum.2temps.fr/viewtopic.php?f=8&t=16752
http://forum.2temps.fr/viewtopic.php?f=8&t=17577
http://www.pit-lane.biz/t875p450-technique-fpe-superkart

Thanks Francis, very interesting, very impressive work.

[katinas]

Francis, very interesting.

One question about RS 125 road chassis. I always be little bit skeptical about street RS 125 cast (maybe not strongest casting alloy) frame beams and swing arm, with ribbed/opened inner side. How this frame perform during the race conditions. Is some flaws with this chassis especially with more powerful engine?
Thanks

[fpayart]

The bike has been modified quite deeply, fork, 250GP wheels with real tires, brakes, but the ribbed beam remains original. For the moment the only fault that can be blamed on him is his weight.
The bike is now quite light, 117kg, should be modify the rocker arm which does not permit the mounting of an effective shock absorber.
We were at the Paul Ricard circuit, last weekend, for the first race of the season, it was the first time that the bike was rolling with its big wheels, the driver is delighted, he found a huge difference in efficiency.
We made good progress in engine and chassis settings, 240kmh at 13200 rpm, in the straight line.
Alas the LIPO battery decided to die during the race...

[Frits Overmars]

... I have a lot of work, especially with a new project of a new complete bike.
We are fortunate in France to still be able to participate in specific races with two-stroke 250cc Grand Prix motorcycles.
Since last year, we participate with two prototypes equipped with Superkart FPE engine.
One from an Aprilia RS250 road chassis and the other from an Aprilia RS125 road chassis.
The experience is encouraging enough that I decide to re-design a new, more compact engine, better suited to the bike.

Some information and pictures:
http://forum.2temps.fr/viewtopic.php?f=8&t=16752
http://forum.2temps.fr/viewtopic.php?f=8&t=17577
http://www.pit-lane.biz/t875p450-technique-fpe-superkartBonjour Francis, comment ça va?
I very much like the idea of an FPE-JBB :yes:.
I noticed that the JBB-frame below is shown in its usual way but the FPE-engine is mirrored, although the lettering on the cylinders is not...
335935335934

[fpayart]

Hello Frits,
Thank you, I'm fine, I'm getting old a little too fast in my opinion.
You're right, it's not a photo montage, it's a complete new engine, I wanted to get closer to the usual configuration for most motorcycles, chain left.
All the study and the drawings are finished, I'm in the manufacturing phase.
I'm sure you'll notice all kinds of interesting details

335936

335937

[katinas]

Hello Frits,
Thank you, I'm fine, I'm getting old a little too fast in my opinion.
You're right, it's not a photo montage, it's a complete new engine, I wanted to get closer to the usual configuration for most motorcycles, chain left.
All the study and the drawings are finished, I'm in the manufacturing phase.
I'm sure you'll notice all kinds of interesting details

335936

335937

Francis, this things made life much, much brighter, I am SO enjoy of your work.
Some time ago, when I look for non telescopic front end, found that this concept is the best from all non telescopic concepts ( strength/weigh, forces distribution, wheel turning). If I remember correctly, it was ATOMO project with Suzuki TL 1000 engine. But this - with 2 stroke 250cc engine - simply amazing, real dream.
Thank you again and meilleurs voeux.

[SwePatrick]

Aha, the methanol may explain the short pipe and the small need for ignition advance because of a low EGT. But since you mentioned a Minarelli base engine, I assumed that an 98 cc version would have a short stroke and a big bore, which would not help blowdown angle.area. The 134° transfer timing won't help either, but it does lower the Helmholtz frequency quite a bit when the crankcase volume is coupled to the cylinder volume at such an early stage in the cycle. So that may explain the preference of the engine for big pipe diameters.

I based my guesswork on an assumed 39,7 mm stroke, 56 mm bore, 130°/198° port timings, 15:1 compression ratio and max.power at 12500 rpm. How far was I off?

It is actually 52mm bore and 46mm stroke.
But still very 'over square' so your guess isn´t totally wrong =)
Compression is dead on 15-1 in total compression.
MOTA says power peak is at 13800rpm, but i have found that MOTA often reports higher rpm than real world.
MOTA also says 40.8 peak power on methanol.

My friend is building the pipe this weekend, so we might soon get an answer if it works =)

[Frits Overmars]

Hello Frits,Thank you, I'm fine, I'm getting old a little too fast in my opinion.
You're right, it's not a photo montage, it's a complete new engine, I wanted to get closer to the usual configuration for most motorcycles, chain left. All the study and the drawings are finished, I'm in the manufacturing phase. I'm sure you'll notice all kinds of interesting details.Very interesting indeed Francis. For me the most remarkable aspect is that you moved the gearbox downward and then rotated the engine forward in order to shorten it.
I think your new engine is more compact and better-looking than the Aprilia RSA250 V-twin (below left).
For those who are not familiar with your superkart engine: below is a comparison between the kart layout (mirrored) and the new layout.
335943 335944335945335946

[dutchpower]

Hello Francis you change it a lot the transfers !!!

[fpayart]

@ Dutchpower,

Be careful, this photo of the transfer ducts represents the sand cores, with positioning apendices for the central core.
In addition, these are the core for the Suzuki RG500 cylinder which is much narrower than the FPE cylinder.

@ Frits,

I applied myself to compact the engine as much as possible, and also to privilege the mechanical accessibility and the flow of air behind the radiator.
During the study, I considered several configurations, tandem, V ...
Finally I chose a V/tanden.
As I reduced the distance between the two crankshafts, I did not have enough room for the base of the two cylinders side by side, so I opened very slightly cylinders , one with respect to the other (5 °)
And I prefer the dynamic balancing of the tandem, to that of the V one.

335947 335948 335949

[husaberg]

@ Dutchpower,

Be careful, this photo of the transfer ducts represents the sand cores, with positioning apendices for the central core.
In addition, these are the core for the Suzuki RG500 cylinder which is much narrower than the FPE cylinder.

@ Frits,

I applied myself to compact the engine as much as possible, and also to privilege the mechanical accessibility and the flow of air behind the radiator.
During the study, I considered several configurations, tandem, V ...
Finally I chose a V/tanden.
As I reduced the distance between the two crankshafts, I did not have enough room for the base of the two cylinders side by side, so I opened very slightly cylinders , one with respect to the other (5 °)
And I prefer the dynamic balancing of the tandem, to that of the V one.

335947 335948 335949

Very elegant Francis
A similar laylout was on the KR250, of course yours has the contrarotating cranks and is much tidier.

[jellert]

@ Dutchpower,

Be careful, this photo of the transfer ducts represents the sand cores, with positioning apendices for the central core.
In addition, these are the core for the Suzuki RG500 cylinder which is much narrower than the FPE cylinder.

@ Frits,

I applied myself to compact the engine as much as possible, and also to privilege the mechanical accessibility and the flow of air behind the radiator.
During the study, I considered several configurations, tandem, V ...
Finally I chose a V/tanden.
As I reduced the distance between the two crankshafts, I did not have enough room for the base of the two cylinders side by side, so I opened very slightly cylinders , one with respect to the other (5 °)
And I prefer the dynamic balancing of the tandem, to that of the V one.

335947 335948 335949

This is amazing work, so it's actually a 5 degree V-twin with all the advantages of a tandem. Love reading about a massive project like this. Do I spot a wobbly style oval to round exhaust spigot in the second picture?

[Peter1962]

@ Frits,

I applied myself to compact the engine as much as possible, and also to privilege the mechanical accessibility and the flow of air behind the radiator.
During the study, I considered several configurations, tandem, V ...
Finally I chose a V/tanden.
As I reduced the distance between the two crankshafts, I did not have enough room for the base of the two cylinders side by side, so I opened very slightly cylinders , one with respect to the other (5 °)
And I prefer the dynamic balancing of the tandem, to that of the V one.

335947 335948 335949

Bonjour Francis, cela fait plaisir de voir que vous êtes toujours active dans la construction et le developpement de moteurs deux temps de competition. :niceone:

Now that the rulebook of the superkart is no longer a technical limit, I see that you are using an electronic powervalve. What is your assessment of the difference between the mechanical and the electronic version of the powervalve ? The carburators are of your own creation ? But, this time with electronic powerjet which was prohibited under superkart rules ?

I am so glad to finally see another JBB chassis with a twin cilinder two stroke engine made in France.
The original was in 1981 or 82 if I am not mistaking.

If I may ask : what is the reason that you chose a tandem and not a V twin like the original engine Jean-Bertrand Bruneau used in '81 ? Does the tandem twin have a technical advantage over a V 90° ?

For balancing : can you elaborate on the choice that whas made for balancing, compared to the natural balance factor of a V twin at 90° please ?

[Frits Overmars]

A similar laylout was on the KR250, of course yours has the contrarotating cranks and is much tidier.335967
It strikes me that in the Kawa KR250 each crankshaft seems to drive a separate clutch gear. To me that only makes sense if each of these clutch gears has its own built-in transmission shock absorber. It won't cure the vibrations of a non-contrarotating tandem-twin though. As far as I know this KR250 was never sold over here.
Can you tell me more about this engine Husa?


what is the reason that you chose a tandem and not a V twin like the original engine Jean-Bertrand Bruneau used in '81 ? Does the tandem twin have a technical advantage over a V 90° ?
For balancing : can you elaborate on the choice that whas made for balancing, compared to the natural balance factor of a V twin at 90° please ?Peter, I suspect that the crankshaft in the JBB V-twin lacked stiffness because of the long unsupported big end pin and the long distance between the main bearings. Besides, an FPE-version will produce a lot more power than the original JBB-twin.

The natural balance of a 90° V-twin is a fact. But strictly speaking an engine like the Aprilia RSA250 is not a V-twin but a W-twin because of the two separate crankshafts. If those are contrarotating, you can achieve good balance at the cost of high internal forces between the main bearings. If it is not, as in the Kawa KR250, there will be a huge rocking couple that cannot be neutralized without additional balance shafts. Suspending the engine in silentblocs, as Kawa did, is a cheapo solution.

[JanBros]

335967
It strikes me that in the Kawa KR250 each crankshaft seems to drive a separate clutch gear. To me that only makes sense if each of these clutch gears has its own built-in transmission shock absorber.

they have Frits : http://kr250.org/KR_home.htm, under servicing you can find the service manual.

direct link to KR250 service manual of clutch : http://kr250.org/manual/KR_manual_chapter_5.pdf

and indeed, never officialy sold in europe.

[husaberg]

335967
It strikes me that in the Kawa KR250 each crankshaft seems to drive a separate clutch gear. To me that only makes sense if each of these clutch gears has its own built-in transmission shock absorber. It won't cure the vibrations of a non-contrarotating tandem-twin though. As far as I know this KR250 was never sold over here.
Can you tell me more about this engine Husa?
.
It appeared in about 84
it was a 180 degree engine both turned in the same direction.
it had a odd reed and dick intake with the carbs facing forwards.
they had a single one piece head like a RDLC
Later version had a atac type exhaust valve built into the cylinder.
I have the disc measurements somewhere
Pretty sure Europe got the similar single cylinder version.
They were also one of the first Japanese production bikes to have a Ffat slide downdraft carb 28TMSS (like a !KT TZR250)
I have a series of pics tucked away.
https://www.kiwibiker.co.nz/forums/album.php?albumid=4840&page=5
They also won the NZ production 250 title when they first came out.

Oh its a series of different teeth on the same gear with the KR250 I assume it just for backlash like the separate teeth on a MB honda counter balancer shaft.
https://www.kiwibiker.co.nz/forums/album.php?albumid=4896&attachmentid=307184
Not sure if the hub was rubber shock absorbed but it likely was.

[Frits Overmars]

Oh its a series of different teeth on the same gear with the KR250 I assume it just for backlash like the separate teeth on a MB honda counter balancer shaft. https://www.kiwibiker.co.nz/forums/album.php?albumid=4896&attachmentid=307184
Not sure if the hub was rubber shock absorbed but it likely was.Nah, I don't think so. The shock absorbers were built into the hub of each primary gear, see below left. They were of the cam-type, with spring-loaded lateral movement, like you'll find in a number of British Torrey Canyon-type engines (below right).
The Kawa clutch hub would only contain some springing that pushes the driven gear and the anti-backlash gear against one another, like on the six-pot Honda CBX1000.
335969 335968

[fpayart]

@ Peter1962,
I think Frits answered all your questions correctly.
"Now that the rulebook of the superkart is no longer a technical limit, I see that you are using an electronic powervalve. What is your assessment of the difference between the mechanical and the electronic version of the powervalve ? The carburators are of your own creation ? But, this time with electronic powerjet which was prohibited under superkart rules ? "
Yes, correct.



@ Husaberg, JanBros,
Thank you for this wealth of information

I had never seen that the Kawasaki engine had both an intake by disc and valves.
I was very interested in this engine, but so far I had not found much information

This one interested me a lot too

335970335971335972335973335974

[JanBros]

This one interested me a lot too

335970335971335972335973335974

the sad news is that you already show about half of what can be found about it on the net :(

here's what we at the KR forum have gathered : http://kr-1s.co.uk/forum/viewtopic.php?t=5556&postdays=0&postorder=asc&start=0

[jasonu]

They also won the NZ production 250 title when they first came out.
.

Aaron Slight???

[motogpdriver]

could this one be able to do the task?
Don't know if it can handle high rpm's or how accurate it is?
It is designed for 4t :woohoo:

[Grumph]

Husa - I think you may be wrong about the KR250 winning a NZ title. I suspect you're getting mixed up with the KR1 S specials produced by Boyles - and a page added to the manual to aid homologation, LOL.

There have been a couple of KR250's modified for local club racing, neither very seriously as parts are a concern. Frits may be amused to learn that invariably the first thing done is to re-phase the cranks. Both the modified ones I know of are now parked up permanently.
I also know of one still on the road which has also been re-phased. More because it simplifies the ignition once the original fails.

[husaberg]

Aaron Slight???I had that argument once, but it wasn' t him.

Husa - I think you may be wrong about the KR250 winning a NZ title. I suspect you're getting mixed up with the KR1 S specials produced by Boyles - and a page added to the manual to aid homologation, LOL.

There have been a couple of KR250's modified for local club racing, neither very seriously as parts are a concern. Frits may be amused to learn that invariably the first thing done is to re-phase the cranks. Both the modified ones I know of are now parked up permanently.
I also know of one still on the road which has also been re-phased. More because it simplifies the ignition once the original fails.
I have it in a mag here
It was the season that ended with the Snydham GP it was def the tandem
I am not sure if it ran the whole championship though on it though he may have started on a RZ250 then finished on the KR250.
Yeah the Boyles change bits is legal as long as you do the min number thick, If it was good enough for the Wire wheel black pipe Katana, it was good enough for Kawaski as well.



Nah, I don't think so. The shock absorbers were built into the hub of each primary gear, see below left. They were of the cam-type, with spring-loaded lateral movement, like you'll find in a number of British Torrey Canyon-type engines (below right).
The Kawa clutch hub would only contain some springing that pushes the driven gear and the anti-backlash gear against one another, like on the six-pot Honda CBX1000.

I should have googled the parts fiche.
Looks like you are 100% Frits, it has a Old pomy like crank shock interlocking cam shock absorber, but with a beville washer set up as a spring.
there is indeed also a rubber damper in the clutch sandwiched with a plate.
Later models also had rubber dampers in the disk valve.
http://www.kr250.org/KR_partsbook.htm
335983335984335987




I had never seen that the Kawasaki engine had both an intake by disc and valves.
I was very interested in this engine, but so far I had not found much information
They called it Krris which is Kawasaki reed rotary induction system.
I wouldn't lose sleep over it, As it wasn't for top end power
Pretty sure the AR125 had the same system which Europe did get in numbers?
335985
if you look where screw 92009 is you can see the reed valve
here is some info

https://www.youtube.com/watch?v=-iT5xjIzjcg
if you look at 1.02 you will see it
https://blog-001.west.edge.storage-yahoo.jp/res/blog-da-14/s302sanr/folder/1056200/26/32087426/img_14?1375532245 (https://blogs.yahoo.co.jp/s302sanr/GALLERY/show_image.html?id=32087426&no=14)https://blog-001.west.edge.storage-yahoo.jp/res/blog-72-19/bgytw146/folder/1015597/59/27433559/img_2?1375820833 (https://blogs.yahoo.co.jp/bgytw146/GALLERY/show_image.html?id=27433559&no=2)
https://blog-001.west.edge.storage-yahoo.jp/res/blog-72-19/bgytw146/folder/1015597/59/27433559/img_11?1375820833 (https://blogs.yahoo.co.jp/bgytw146/GALLERY/show_image.html?id=27433559&no=11)https://blog-001.west.edge.storage-yahoo.jp/res/blog-72-19/bgytw146/folder/1015597/59/27433559/img_8?1375820833 (https://blogs.yahoo.co.jp/bgytw146/GALLERY/show_image.html?id=27433559&no=8)https://blog-001.west.edge.storage-yahoo.jp/res/blog-72-19/bgytw146/folder/1015597/59/27433559/img_3?1375820833 (https://rdsig.yahoo.co.jp/blog/gallery/image/main/RV=1/RU=aHR0cHM6Ly9ibG9ncy55YWhvby5jby5qcC9iZ3l0dzE0Ni9 HQUxMRVJZL3Nob3dfaW1hZ2VfdjIuaHRtbD9pZD1odHRwcyUzQ SUyRiUyRmJsb2ctMDAxLndlc3QuZWRnZS5zdG9yYWdlLXlhaG9 vLmpwJTJGcmVzJTJGYmxvZy03Mi0xOSUyRmJneXR3MTQ2JTJGZ m9sZGVyJTJGMTAxNTU5NyUyRjU5JTJGMjc0MzM1NTklMkZpbWd fMyUzRjEzNzU4MjA4MzMmaT0x)
http://twwhlspls.com/tandem-twin/
http://www.kr250.org/KR_home.htm
335982

[jasonu]

I had that argument once, but it wasn' t him.

.

Eddie Kattenburg perhaps.

[husaberg]

Eddie Kattenburg perhaps.
Just for giggles aussie

https://www.youtube.com/watch?v=PCeyATZ4u6Q

[Flettner]

Husaberg, the last hoorah for the rotary valve.
What a pity dumbarse Kawasaki gave up on the RV and just followed the others with reeds, never to do any good again with the twostroke, dickheads.

The Gibs experiment on my 360 is a testing vehicle for the RV to be revived, and set into the 700 V twin, variable rotary valve induction engine. Tractability of the reed down low with the all out power of the RV top end.
That's the trouble with RV engines, if you want hard out top end RV timing they are all but unrideable off the pipe.
But who am I to say, you all know this anyway.
Love that video though.

[F5 Dave]

You forget how far road tyres have come. Not much lean angle going on there.

[husaberg]

Husaberg, the last hoorah for the rotary valve.
What a pity dumbarse Kawasaki gave up on the RV and just followed the others with reeds, never to do any good again with the twostroke, dickheads.

The Gibs experiment on my 360 is a testing vehicle for the RV to be revived, and set into the 700 V twin, variable rotary valve induction engine. Tractability of the reed down low with the all out power of the RV top end.
That's the trouble with RV engines, if you want hard out top end RV timing they are all but unrideable off the pipe.
But who am I to say, you all know this anyway.
Love that video though.

I was reading the other day about the OW60 that Croz rode which was the Yamaha copy of the RG500.
It was dyno'ed 156HP Rear Wheel in 1983.
This was a massive increase over the Inline 4 piston port OW48R Yamaha previously had. and a huge decrease in weight over the first square 4 OW54
Kenny only rode it in a few races opting for the Rotary valve V4 the the rotary valves inside the V. The OW61.
The Yamaha mechanics claimed the OW61 it was the worst bike Yamaha ever made. Likely cost Kenny the championship.

Croz on the other hand only had access to the older OW60 in the AGO team. He rode the bike and realised that something was really wrong in the front end so with Yamaha permission Radar hacked off the steering head to get rid of the funny geometry Kenny had built in and set it up the same as a RG500.
He loved it then. It was 2 seconds a lap faster than it was previously.
Although Croz finished second it could have gone better, The story goes that Radar Cullen and Croz and the other mechanics would build a bike only to come back and find Ago had lent it out to an Italian for a local meeting and it would be broken crashed or out of spares right before the next GP. Yet he still finished second in the championship. Kenny finished 4th.
What I never knew was the Yamaha OW60 was triple port with a PV.
I linked the article the other day neat bikes those 80's GP bikes so light and spindly and hand built.
One thing that's neat about the OW60 is the radiator is actually inside the frame allowing the front wheel to be closer to the frame.
335992335993335994335995335996335997
Anyway what I do know is I could never do the stuff you do Neil, you are an artist with a mill.
https://www.pressreader.com/uk/classic-racer/20171219/282540133675797

https://www.pressreader.com/uk/classic-racer/20171219/282591673283349/textview

[TZ350]

What a pity dumbarse Kawasaki gave up on the RV and just followed the others with reeds, never to do any good again with a twostroke, dickheads.

Yep, not much inovative engineering comes from design by accountancy.

335998

[F5 Dave]

To be fair their reed KX and KDX of the time did pretty ok I thought.

[Flettner]

To be fair their reed KX and KDX of the time did pretty ok I thought.

yes but imagine if they were rotary valve, they could have been much better (in my opinion) and like Subaru, sales by point of difference. Silly old fools like me would go out of our way to purchase a RV engine bike, if not just because they are different. And now the age old problem of sharp power delivery is gone. And also now a 'relatively' clean (well better than a carburetor) exhaust with TPI.
I just can't wait to see how this 360 goes, if it's anything like my injected Bighorn engine it will be all worth the work.
But boy there is a lot of work in it yet.
made a stainless steel water pump drive shaft today and fitted the plastic gear to it, little battles.

[husaberg]

What was the last serious performance road bike made that had disc valves RG500? or KR250? both were made up until 1987 any others?
No Rob I am not including the GP125 Suzuki.:innocent:

[TZ350]

I just can't wait to see how this 360 goes,

Me 2 ......... very exciting .. :2thumbsup

[katinas]

Thanks Husa for KR/OW story and nice Video.
Just remember my meditation in second hand motorcycle shop, when left hand was on KR 250 ( red/black color with all exhaust adjustments ) other hand on NS 250. I really like KR engine, but NS chassis and 17 inch rear wheel overweight (three others two strokers in this shop, was RZ 250 and two RG 250).
Later, when guy who bought KR asked me adjust carburetors, I was very surprised, when noticed additional reeds.
He was not a two stroke man and I hear the story, that after usual two stroke caprice he burned down this KR. Maybe its true, because I've never seen this KR anymore.

[SwePatrick]

I have been simulating for hours for my friends 98cc minarelliengine.

One thing that amases me is section 2 on this printout.
Everytime i add a 'square' piece in the header it gives me a boost in power.
And almost everytime it raises the whole curve(and previous projects have shown the same in real life dyno)

By adding this i can run harder tapering on section 1 and 3 to acheive the same 'medium' tapering as a long header that replaces 1.2.3 sections would have to meet cylinder and section 4.

Anybody noticed the same?

Rgds


335919

I quote my self if anybody want to hear the progress.
First pull on dyno, very raw and just setup to start and be safe in 'break in'
29.2hp to the wheel at 14300rpm on 98 octane pump fuel.
It revs very freely was the first spontaneus reaction, they pulled it all the way to 17000rpm by mistake ;)
I´m sorry to say that i isn´t there where they dyno it, we just have contact through the phone as is.

Very low barometerpressure today in Sundsvall, only 1002hPa

[teriks]

@ Dutchpower,

Be careful, this photo of the transfer ducts represents the sand cores, with positioning apendices for the central core.
In addition, these are the core for the Suzuki RG500 cylinder which is much narrower than the FPE cylinder.

@ Frits,

I applied myself to compact the engine as much as possible, and also to privilege the mechanical accessibility and the flow of air behind the radiator.
During the study, I considered several configurations, tandem, V ...
Finally I chose a V/tanden.
As I reduced the distance between the two crankshafts, I did not have enough room for the base of the two cylinders side by side, so I opened very slightly cylinders , one with respect to the other (5 °)
And I prefer the dynamic balancing of the tandem, to that of the V one.

335947 335948 335949
Beautiful! I can for sure appreciate the amount of hours behind such a model.
Even more so after spending _way_ too much time modelling a propeller and mold lately.

[TZ350]

I quote my self if anybody want to hear the progress.


Very interesting, I would love to hear more as the project progresses.

[F5 Dave]

yes but imagine if they were rotary valve, they could have been much better (in my opinion) and like Subaru, sales by point of difference. Silly old fools like me would go out of our way to purchase a RV engine bike, if not just because they are different. And now the age old problem of sharp power delivery is gone. And also now a 'relatively' clean (well better than a carburetor) exhaust with TPI.
I just can't wait to see how this 360 goes, if it's anything like my injected Bighorn engine it will be all worth the work.
But boy there is a lot of work in it yet.
made a stainless steel water pump drive shaft today and fitted the plastic gear to it, little battles.
I've only had one RV dirt ike. One issue was it loaded up pretty bad going down a long hill closed throttle so if you encountered something you wanted to blip to get the front wheel over it did nothing for about a second by which time you had already bounced over it.
the other issue was it had about 4" of ground clearance. . . Because it was s GP100 with knobblies:lol:

[Flettner]

I've only had one RV dirt ike. One issue was it loaded up pretty bad going down a long hill closed throttle so if you encountered something you wanted to blip to get the front wheel over it did nothing for about a second by which time you had already bounced over it.
the other issue was it had about 4" of ground clearance. . . Because it was s GP100 with knobblies:lol:

don't let truth get in the way of a good story, yes they were a bit like that. How big a cut away was your RV?
CanAm (rotax), ran with RV for a long time and got away with it.
Obviously this TIP/sliding gibs will take care of those issues these days.

[Nath88]

I'm in the process of a top end rebuild on the YZ250, I've decided to go 2.1mm larger on the bore since the cylinder needs replating anyway and the pistons are readily available.
At the moment the cylinder has a double base gasket, all the porting looks as cast.
However I've noticed a few oddities:
-The floor of the transfers is about 1.4mm below the piston edge at BDC.. Why would it be like this? Can I raise the port floor with something?
-There is a large lip (protrudes approx 0.5mm into the flow path) around all of the ports except the main exhaust, the overbore should cut through all of these, will that be a problem?

My plan is to:
-Measure the heights of all ports as they are
-Have the cylinder bored 2.1mm oversize
-Clean up the port edges, in case the lips aren't completely removed
-Recheck heights of the ports, hopefully they haven't changed too much.
-Radius all port edges
-Remove big casting flash but leave the ports standard.
-Smooth the transition from the aux exhaust ports into the main duct?
-Smooth/enlarge the Boyesen ports
-Have Nikasil applied

Does this all sound reasonable? I'm happy with the engine's power delivery, don't really want to mess it up.

[Flettner]

nath88, are you going to run the TPI?
PM me and I'll help you with the 'mark two' setup if you like.

[F5 Dave]

don't let truth get in the way of a good story, yes they were a bit like that. How big a cut away was your RV?
CanAm (rotax), ran with RV for a long time and got away with it.
Obviously this TIP/sliding gibs will take care of those issues these days.

The story was really for the porpoise of entertainment. There can't have been a much less suited dirt bike. Although I've never ridden old brit attempts.

But it would be interesting to know how a modern and clever approach hopefully sidesteps a potential issue.
Looking forward to a ride account and YouTube of the bike in action. 360 should really rip in the dirt.

[peewee]

normally i dont like the idea of using a larger piston unless theres a real good reason to do so. especially if the new piston is heavier. i cant think of why yamaha would want the port floors below the piston top but alot of trail riders like to machine a few mm off the bottom deck and drop the cylinder down. supposedly it gives better low rpm power. was the cylinder purchased second hand ? if the piston top rises above the cyl top deck then its likely someone has machined the bottom. you can thank eric gorr as i think he may have been the one who started the cyl lowering trend with dirtbike riders

[Nath88]

normally i dont like the idea of using a larger piston unless theres a real good reason to do so. especially if the new piston is heavier. i cant think of why yamaha would want the port floors below the piston top but alot of trail riders like to machine a few mm off the bottom deck and drop the cylinder down. supposedly it gives better low rpm power. was the cylinder purchased second hand ? if the piston top rises above the cyl top deck then its likely someone has machined the bottom. you can thank eric gorr as i think he may have been the one who started the cyl lowering trend with dirtbike riders

I'm starting to think I should have stayed at stock bore, especially since the new piston has a 1mm wide flat step around the edge of the dome. Will make cutting the head a bit more difficult and probably a bit worse flow across the edge when the port is just opening.
The piston edge is 1.3mm below the deck with 2 base gaskets, the top would be above the deck for sure with the dome. May have been machined, I'll have a look for evidence.

Cylinder came with the bike, not sure of it's history. I'll measure all the ports tonight see where they're at.

[F5 Dave]

Think yourelf lucky, the GasGas come with the Exhaust floor not full exposed by the piston, sort of a reverse of Jans port floor raising. Overseas forum members all seem obsessed with raising the barrel so it matches. You know, like for a squillionth of a second, and to hell with the timing.

[SwePatrick]

Very interesting, I would love to hear more as the project progresses.

Yes, i´ll post the progress. :)
They did a fun test yesterday to see if it responded on a small carburetor.
27mm old round throttle keihin made 28.0hp to the wheel.

Today they will go back to 32-34mm carb again and test(29.2 was with 32mm carb), but as they haven´t got any racefuel(they want the engines 'footprint' before going to methanol) yet they will be very careful.

As i understood from phonecall, they had no corrections made on that 29.2 pull, it might have been around 29.5-29.8hp
And he also mentioned they had problems with slip on the dynoroller.

So i´m excited, as i suspect it actually burned up some power due to tireslip, pipe is tuned to 14000rpm and they got the power at 14300rpm as the peak might have rolled over.

[SwePatrick]

34.1hp at this point, but at very high rpm´s 16467rpm.
But, i figure it is because petrol in a pipe designed for methanol.

[SwePatrick]

Oops.. fast update now. =)
They tested E85 fuel, 35,3hp at 16000rpm
As suspected, the power will be at lower rpm on methanol in future pulls.

[wobbly]

Having been thru the exercise of proving that a hot exhaust duct is no good for power I tested ways of getting better cooling in the TM kart engines
I work on.
The first was to figure out why the factory originally intended to have all the cooling water enter the cylinder via ports under the duct, from the case,and then deleted this
and added a hose to feed water in above the exhaust port - from the side..
After many long hours of thought and trial tests, here is the result.
With all the water flowing over the hot duct, it heats ALL the water,that then flows over the transfer tops,into the head and out.
Thus the transfers are actually being heated up,always a bad idea.
So I first drilled two 3mm holes up thru the plugs under the exhaust duct, and added a water fitting hole into the cylinder facing the boost port.
This allowed some cooling of the duct, but forced the coldest water volume over the transfers.
Result - 1 to 1.5 Hp everywhere.
But the tech minions decided this was illegal,as I had made an extra hole in the cylinder that wasn't shown in the homologation papers.
OK, so fuck them,the papers dont show any water fittings at all, so i made a long screw in manifold that also directs all the cold water, back, over the transfers.
Result, almost the same power, and 1st and 2nd at the National champs over Easter.

[Nath88]

Measured the port timing on the YZ250, cylinder raised 0.4mm.
Exhaust PV Open 185° Blowdown 34°
Exhaust PV Closed 160° Blowdown 22°
Aux Exhaust 185°
Rear Transfer 120°
Main Transfers 117°

Exhaust seems right but transfers seem low.. The only reference I could find says stock is 121 degrees, can anyone back that up? Should the rear transfer port open first?

[F5 Dave]

That's quite a stagger. Sorry did you bore this significantly? Transfer angled will be more affected.

[Nath88]

That's quite a stagger. Sorry did you bore this significantly? Transfer angled will be more affected.

Nope, stock cylinder... I'm measuring so I can see the difference once it's bored. Seems like the transfer ports are cast about 1mm too low. Would explain the piston/port mismatch at BDC.

[jfn2]

Woobly:

Excellent info. Could you explain more on the long manifold. I'm not to familiar with the TM's. Also will the 2-3mm holes be large enough to cool the bottom of the exhaust duct? Maybe more of a compromise is needed. Like 5mm holes or 4mm, or 6mm? Just wondering. I'll have to try this on my KTM's.

[SwePatrick]

Having been thru the exercise of proving that a hot exhaust duct is no good for power I tested ways of getting better cooling in the TM kart engines
I work on.
The first was to figure out why the factory originally intended to have all the cooling water enter the cylinder via ports under the duct, from the case,and then deleted this
and added a hose to feed water in above the exhaust port - from the side..
After many long hours of thought and trial tests, here is the result.
With all the water flowing over the hot duct, it heats ALL the water,that then flows over the transfer tops,into the head and out.
Thus the transfers are actually being heated up,always a bad idea.
So I first drilled two 3mm holes up thru the plugs under the exhaust duct, and added a water fitting hole into the cylinder facing the boost port.
This allowed some cooling of the duct, but forced the coldest water volume over the transfers.
Result - 1 to 1.5 Hp everywhere.
But the tech minions decided this was illegal,as I had made an extra hole in the cylinder that wasn't shown in the homologation papers.
OK, so fuck them,the papers dont show any water fittings at all, so i made a long screw in manifold that also directs all the cold water, back, over the transfers.
Result, almost the same power, and 1st and 2nd at the National champs over Easter.

Nice!

That verifies my ideas i was talking about earlier =)

Thanks for sharing.

[DoldGuy]

I'm in the process of a top end rebuild on the YZ250, I've decided to go 2.1mm larger on the bore since the cylinder needs replating anyway and the pistons are readily available.
At the moment the cylinder has a double base gasket, all the porting looks as cast.
However I've noticed a few oddities:
-The floor of the transfers is about 1.4mm below the piston edge at BDC.. Why would it be like this? Can I raise the port floor with something?
-There is a large lip (protrudes approx 0.5mm into the flow path) around all of the ports except the main exhaust, the overbore should cut through all of these, will that be a problem?

My plan is to:
-Measure the heights of all ports as they are
-Have the cylinder bored 2.1mm oversize
-Clean up the port edges, in case the lips aren't completely removed
-Recheck heights of the ports, hopefully they haven't changed too much.
-Radius all port edges
-Remove big casting flash but leave the ports standard.
-Smooth the transition from the aux exhaust ports into the main duct?
-Smooth/enlarge the Boyesen ports
-Have Nikasil applied

Does this all sound reasonable? I'm happy with the engine's power delivery, don't really want to mess it up.

Nath88,

Most late model MX 250’s have about 184/185 exhaust 118/120 Transfers. When you overbore, the roof angles will lower the port window (sometimes a lot). The “lip” you referred to, is it on the sides of the port windows (you want those) or on the roof/floor of the window? I have not had my hands on a stock late YZ Cylinder but know that some tuners stagger the transfers for a broader power curve.

Enjoy your post & videos on the FI, keep sharing!

[Flettner]

so what are we talking, twin scroll water pump, twin Radiators. One feeding the crankcase, cylinder, head and one feeding the exhaust stub only?

[husaberg]

so what are we talking, twin scroll water pump, twin Radiators. One feeding the crankcase, cylinder, head and one feeding the exhaust stub only?

Ages I suggested a twin circuit set up so the crankcase only got cooled by ultra cold water, that idea was poo pooed by the panel.

[Flettner]

Ages I suggested a twin circuit set up so the crankcase only got cooled by ultra cold water, that idea was poo pooed by the panel.

Fuck the poo poo panel
The 360 has two Radiators and I've got a twin scroll water pump.Worth a crack?

[katinas]

Seems like the transfer ports are cast about 1mm too low.

Its good point to try rounded piston with modified head. Interesting, how the longer stroke engine react to his.

After first training with rounded piston on SX 85, boy was happy. From side, seems like he can hold longer time with one gear.
First race after two weeks, so it would be more clear.

PS "- Radius all port edges-" be careful with radius on transfer windows top edges (not too much, just for rings ) because of back flow. Page 1900 Frits post .

[husaberg]

Fuck the poo poo panel
The 360 has two Radiators and I've got a twin scroll water pump.Worth a crack?
Id rather not and I think so, you can figure out the order to which I replied:lol:

[TZ350]

Fuck the poo poo panel

Always a good philosophy .... Fuck the poo poo ers and do your own thing.

[wobbly]

The trick is to identify what areas need to be cooled, and those that dont contribute more power by being exposed to the coolest water.
Then to find a simply way of keeping the different temp deltas separated.
The best scenario I have used was in the TZ400 classic racer, and then the TZ350 LSR bike.
Cold water enters the cylinder at the rear,and the deck surface is arranged to force all the cold water over the transfers.
The flow then surrounds the Exhaust duct area, then is allowed to flow upward into the front of the head.
This warmed up liquid then runs around the inserts, with good access to the plug threads and the squish area,subsequently leaving the head at the rear of the engine again.
But even in this scenario you have opposing requirements in the same vicinity.
The plug threads and the squish need good cooling, whereas the combustion chamber can be as hot as can be tolerated, to reduce the temp difference between the expanding gas and
the surface it impinges upon.
Coating the chamber with ceramic does just that.

In the TM all I could attempt to do was keep the hot water and the cold water separated and doing the best job,by allowing the hot water from the exhaust to enter the head directly above that area.
Thenat the same time force the main flow of cold water from the case cooling chamber to cool the transfers and enter the head at the rear.
The best scenario would be to keep the chamber between the crankcase and the gearbox, but then run that cold water over the mains to enter the cylinder at the back - just like the TZ setup.

[Frits Overmars]

...the tech minions decided this was illegalWob, what do the tech minions say about painting? Surely they can't object to that, can they?
Now there happens to be a paint that is not too good at conducting heat. In fact it was developed to heat-protect Soviet satellites. But it works in two-strokes too.
If you coat the crankcases and the transfer ducts internally, the temperature of the gearbox oil and the wall temperature of the transfer ducts won't matter any more.
You can get the stuff at http://emot.nl/contact.php.
336012

[SwePatrick]

Wob, what do the tech minions say about painting? Surely they can't object to that, can they?
Now there happens to be a paint that is not too good at conducting heat. In fact it was developed to heat-protect Soviet satellites. But it works in two-strokes too.
If you coat the crankcases and the transfer ducts internally, the temperature of the gearbox oil and the wall temperature of the transfer ducts won't matter any more.
You can get the stuff at http://emot.nl/contact.php.
336012

An older project i´ve got has this mod actually.
But i blended my own coating.
It is a ceramic weldingspray that protects from weldsputter that i blended up with some ordinary 2k paint.
Then brush painted it onto the crankhousing.

I testpainted first on a aluminium sheet and heated it up from behind with a torch, it worked =)
But cant rememer any numbers sadly enough :(

Edit: i tested with a IR gun.

[Frits Overmars]

An older project i´ve got has this mod actually. But i blended my own coating. It is a ceramic weldingspray that protects from weldsputter that i blended up with some ordinary 2k paint. Then brush painted it onto the crankhousing. I testpainted first on a aluminium sheet and heated it up from behind with a torch, it worked =).Patrick, are you still using this on current projects? And if not, why not?

[SwePatrick]

Patrick, are you still using this on current projects? And if not, why not?

Not on my current project, no.
This because of methanol, the engine has problem reaching temprature as is ;)

Problem with methanol is that you actually need some heat to make the fuel vaporize, but i´m sure you already knew that =)

[JanBros]

working on an excel for T.A's,A.A's, ...for cylinder ports, and just wanted to check if my thinking is correct :

from the RSA we know that 12500=(110315 * 1000)/((124.8 + 8.6) * 66.16) or in units : RPM=(A.A * 1000)/((SV + CCV) * STA) (SV = swept volume, CCV = combustion chambre vol)

so I recalculate the RSA's STA for the RPM I want my engine to perform best at, with NewSTA=(A.A * 1000)/((SV + CCV) * NewRPM) ,
and then transform it to the formula NewRPM = (A.A * 1000)/((SV + CCV) * NewSTA).

for the engine I want to develop, I have the formula for BMEP :
BMEP=(BHP * 448162)/(SV * RPM) (SV is in ccm3 , 448162 is a constant to have all units matching) in which of course RPM = NewRPM from the RSA calculations.

since both RPM's are the same, I can enter the RSA calculation into the BMEP formula :

BMEP = (BHP * 448162 * (SV + CCV) * NewSTA)/(SV * A.A * 1000)

and since I've made an edjucated guess about the BMEP and BHP I want at my "new" RPM, with a certain Head Volume, I can determine the needed Angle.Area :

A.A = (BHP * 448162 * (SV + CCV) * NewSTA)/(SV * BMEP * 1000)

correct or flawed ?

[wobbly]

Ha ha, I already use what is called a Hyper Coating,a thermal barrier coating usually used for retaining heat in exhaust systems.
See here :http://www.hpcoatings.co.nz/ExhaustHeatManagement.aspx#HiPerCoat_Extreme.
I just happened to see the inside of a special race engine at TM that had a black " coating " of some sort.
The legality could strictly be questioned, as a basic rule of the class is " no added material ",but the coating has never been questioned by tech.
Let alone the clear thermal barrier coating in the combustion chamber, that you cant see when oil residue is burnt onto its surface.

JanBros - the big problem with trying to replicate the STA and or bmep of the Aprilia is that this engine was R&D'd to death on both the dyno and the flow bench.
The STA numbers nowhere near match,as the Blowdown Cd is hugely affected by the port exit geometry,and this works way better than the raw numbers generated by the simply calculated area.
Then you have a plethora of tiny details ( such as PWM powerjet operation ) and unless you replicate all of this synergy,the numbers you are trying to simulate in your own project are stuff of daydreams.

[Flettner]

emissions problem solved

[mattology]

emissions problem solved

are you going to make it a side bleed?

[Flettner]

yes, off the mid section.
And yes I will weld a knob over the point but first I might just paint it up like a missile for a while.
Years ago I built a uniflow engine jet boat, ran four chambers. They were too long for the short boat so I ran mid section bleed off. On arrival to the boat ramp there was a police training school happening there. As I got out of the car I had several concerned officers confront me asking why I had four missiles pointing out the back of my boat. Took quite a while to convince them that they were in fact exhausts, as in connected to the engine.
Had I known i was going to meet these officers I would have painted them up like missiles, you know with red and yellow tips. Those officers watched me for some time, I don't think they trusted me, dumbarses.
here it is in it's earlier form with just Rotax muffler on it.
Not held at full throttle until later in the video at 5,20. Crank case charged, four pistons, two combustion chambers. Two crankshaft banks. Home cast pistons, fires as a single.
https://youtu.be/uiXsPkP9jvw
https://youtu.be/BPr694nlUKE

I did say years ago!

[Nath88]

Nath88,

Most late model MX 250’s have about 184/185 exhaust 118/120 Transfers. When you overbore, the roof angles will lower the port window (sometimes a lot). The “lip” you referred to, is it on the sides of the port windows (you want those) or on the roof/floor of the window? I have not had my hands on a stock late YZ Cylinder but know that some tuners stagger the transfers for a broader power curve.

Enjoy your post & videos on the FI, keep sharing!

Thanks for the info! I foolishly forgot to measure the roof angles, hopefully they don't change too much with the overbore, I'm going to aim for 189/190 on exhaust, 123 on rear transfer and 121 on main transfers. While retaining the standard roof angles/widths.

I want to investigate staggering the aux exhaust ports above the main maybe 190 aux, 188 main. I'm sure the answer will lie somewhere in this forum.

The lips are the whole way around the port, the cylinder has been replated before, so that may be a contributor. I'll get the guy to pay close attention there when he corrects the chamfer after plating.

[wobbly]

Lifting the Aux is a big mistake.It was done years ago in a Kawasaki MX 125 but they alone were controlled by a PV.
Even then it didnt work at all well.
You need at least 4* duration stagger below the main Ex,or all the mid evaporates.
Same with the transfers, why are you lifting the B above the main, this also kills the lower mid power.
For a wider band width you need proper dropping stagger with the A port highest.
When you overbore, the ducts with steeper angles,like the A and C will drop way more than the flatter B roof, so this needs to be corrected before plating, as does putting a proper chamfer
into the top and bottom of the main Exhaust.
Having a chrome lip all around the ports simply means the plater was a bloody lazy cheapskate.
Instead of just guessing all these port numbers,there are plenty of STA or Angle area calculators available to keep the relative power capability in line.

[Nath88]

Lifting the Aux is a big mistake.It was done years ago in a Kawasaki MX 125 but they alone were controlled by a PV.
Even then it didnt work at all well.
You need at least 4* duration stagger below the main Ex,or all the mid evaporates.
Same with the transfers, why are you lifting the B above the main, this also kills the lower mid power.
For a wider band width you need proper dropping stagger with the A port highest.
When you overbore, the ducts with steeper angles,like the A and C will drop way more than the flatter B roof, so this needs to be corrected before plating, as does putting a proper chamfer
into the top and bottom of the main Exhaust.
Having a chrome lip all around the ports simply means the plater was a bloody lazy cheapskate.
Instead of just guessing all these port numbers,there are plenty of STA or Angle area calculators available to keep the relative power capability in line.

My bad terminology has caused confusion. Stock is:
Main Exhaust: 185°
Aux Exhaust: 185°
A port: 117°
B port: 117°
C port: 120°

So 'conventional stagger' A higher than B & C gives greater bandwidth, and 'reverse stagger' B & C higher than A gives a higher peak, if all ports are level is that somewhere in between?
So if I raise the main exhaust port to 189, I should leave the aux ports where they are at 185.

I'll measure the ports and use a calculator to see where it's at. I'm going to look into the radiused exhaust edge also. Cheers for the advice, I have a lot to think about.

[wobbly]

Proper conventional stagger has all 3 ports dropping, and as the boost is going to be very low with the overbore,this makes it easy to implement.
Yes, lifting the main and leaving the Aux is a good move,but absolutely no need for an Exhaust timing radius,as that was done solely to re calibrate the effective Cd
and balance the Blowdown flow to the transfer STA.
You can achieve way more Blowdown than is needed with conventional means.

[SwePatrick]

I simulated staggered ports against reverse stagger yesterday in MOTA.
Almost no difference.
Reverse stagger had a small advantage at torque peak, about 0.5hp

It suprised me actually.

[lohring]

The problem with one dimensional sims is that they don't actually simulate scavenging, only the flow and pressure pulses through the engine. EngMod2T, a much more accurate sim than MOTA, still only uses scavenging models to determine scavenging efficiency. The fine details of scavenging flow need computer flow simulations to investigate. An easier method is the dyno. Two stroke power is very sensitive to scavenging efficiency.

Lohring Miller

[peewee]

wob have you ever grinded a small groove into the top portion of a lectron needle like the picture (that's not my actual needle but just a random internet pic for illustration) ? I think this should allow more fuel at throttle close position. Ive already had the needle taper grinded more but I suspect it wont be enough, although I haven't ran the engine yet because of the weather. and the steeper you grind the taper at the top, it grinds into the needle threads , which hold the needle into the slide. so I don't want to grind the taper much more because it is removing more and more threads. this is why im thinking of another method to supply more fuel. im thinking I can grind a very shallow groove to start with and try it. if it still runs away I can continue to grind it wider and deeper as needed

[Juho_]

I quote my self if anybody want to hear the progress.
First pull on dyno, very raw and just setup to start and be safe in 'break in'
29.2hp to the wheel at 14300rpm on 98 octane pump fuel.
It revs very freely was the first spontaneus reaction, they pulled it all the way to 17000rpm by mistake ;)
I´m sorry to say that i isn´t there where they dyno it, we just have contact through the phone as is.

Very low barometerpressure today in Sundsvall, only 1002hPa
Would you like to share more information about the engine ?
I'm very interested about your project. Great power and a lot of revs !

[wobbly]

Peewee, the groove idea has been used bu Lectron to get more flow at WOT,as the problem is that you get to a point where the needle isnt supported
sufficiently around its OD.
But there is no need to grind anywhere near the threads,that portion of the needle isnt in the hole in the body,so has no effect on the flow at all.
You can step down the flat a heap, where the stock taper feathers out to nothing.
I would fit the needle to a slide ,sit it at idle height,then measure up the hole from the bottom.
Take the needle off the slide, set it at the same height, and mark where it intersects the hole at the top,that is where your groove or deeper taper needs to start.
The other way to change the flow dramatically is to raise the fuel level in the bowl.
Lectrons are very sensitive to the height in the bowl at and around idle/transition.

[peewee]

yes thats what i plan to do. just grind a groove at the upper section of the needle where it intersection the top of the tube at idle position. i figure this is easier than trying to accuratly grind down the taper.

[Flettner]

so what are we talking, twin scroll water pump, twin Radiators. One feeding the crankcase, cylinder, head and one feeding the exhaust stub only?

nah, single scroll pump, running the 360 on E85 it should run cool enough anyway.

[jbiplane]

emissions problem solved

When we use our proprietary Engine Management System which
controls fuel injection + ignition we got at least (compare carburetor):
4% more power at full throttle and 7% at medium rpm
30% of fuel economy
50% less CO in exhaust
https://paraplan.ru/forum/files/14258/KVgXpIkb.jpg
https://paraplan.ru/forum/files/14258/0d90r97V.jpg

Tested on UAVs. Hope will work nicely on high rpm engines.
Would be gratefull for english grammar and stylistic corrections

[Flettner]

jbiplane, thankyou.

I've been using the NZ made Link ECU. Used it on my Kawasaki crankcase/transfer port injected twostroke (shown in the picture, 2008) and also on the first B port TPI twostroke, YZ250 (2012)
This next development requires twin throttle control, detonation control and input sampling. The Link suits my needs for the moment.

[jbiplane]

Hi Flettner


This next development requires twin throttle control
I see why :cool:

I've been using the NZ made Link ECU
Its always nice to have local fuel injection solution supplier.

We had to develop EMS after few years ecotrons experience cause had unsufficient support and hardware problems. Finally we created our system with
1. End user price 200$
2. Completely compatible with very good EFI Analytics TunerStudio tuning software.
http://www.tunerstudio.com/index.php/tuner-studio
3. Completely open solution. It can use numerous third side components like fuel pump and nozzles available in customer local shops.
4. Spark energy control. Easy possible get spark which burn out sheet of paper.

We produce as well very lighweight starters-generators and 98% effecient voltage rectifiers which are relatively expensive, but may be rational for high end racing solutions. Can place additional information in this thread if someone interested.
As UAV engine company I don't completelly understant motocycle comunity needs, though for me reading this forum rather usefull.

[teriks]

jbiplane, that looks really professional!
Almost sorry I have no use for it... ;)

[husaberg]

Tested on UAVs. Hope will work nicely on high rpm engines.
Would be gratefull for english grammar and stylistic corrections
JB you are a Russian company making drone engines should be be worried:whistle:
If i understood your post correct your starter also runs as a generator much like an old Villiers and bubblecars had although they could also reverse the engine rotation have you considered other non flight applications for a small light efficient engine.
336047
https://en.wikipedia.org/wiki/SIBA_Elektrik_G.m.b.H

[Jannem]

When we use our proprietary Engine Management System which
controls fuel injection + ignition

Seems the pinout table is missing ignition part of the system. Is that just a partial table you posted?

[Jannem]

It seems triple exhaust benefits from contracting the nozzle to 75%, but single only to 90%. Can anyone explain the reason why single would like to run at lower speed? Say in a case where you run the single port in small cc engine and you get the blowdown STA where it needs to be for the revs.

Ours is at 80%, and I'm wondering what to do with it.

No takers for this one at the time, but have thought about it. Theoretically it could be due to the fact that triple port of the same entry area is better from the velocity/pressure distribution standpoint due to being wider at the same area. This will reduce the local choking in the port and the nozzle.

Along that line of thought the triple port could be made even more efficient by putting the aux port exits into the main as close to the floor of the main as possible. This would improve the pressure distribution further potentially allowing even smaller nozzle area and potentially eliminating the need for ”detonation fin” in the nozzle, which I believe does what it does by improving pressure distribution at the high speed portion of the exhaust duct. With this approach I wouldn’t put the ”bulges” into the main for the auxes, as it would add area to the already low speed portion of the main, reducing the potential benefit.

It would also improve the efficiency of the aux ports by making the entry angle smaller.

Just a thought excercise, but it should not disagree with the physics of the gas flow.

[jbiplane]

Seems the pinout table is missing ignition part of the system. Is that just a partial table you posted?

Thanks. You find an error in English translation! I corrected the table. Pin 18 and 19 responsible for 2 ignition lines.

[jbiplane]

JB you are a Russian company making drone engines should be be worried:whistle:
If i understood your post correct your starter also runs as a generator

We dont have military licenses (tried to get, but no sucsess) and produce mostly engines for geological drones and precise earth reliefs 3D scans. Our main customer is: http://uav-siberia.com/en/ Now we want extend our activities and product range.

Says next month we will start production of 2 cylinder boxer paramotor engines.

Related starter generator. Yes its work the way you mentioned.
We produce as well hybrid
11hp inline ICE engine
+ ~ 9hp electrical motor-generator.
You can launch drone on both engines and use electric or ICE during flight. This way we have at least 40% more range.

We start company in 2016 and actual web site dont reflect what we already achive. Will drastically update site in 2 month.

[Jannem]

Thanks. You find an error in English translation!
Yes, there is an error in the table. Pins 18 and 19 are for ignitions chanels, not injection. Will correct it.
That is almost magical intuition, when I actually missed seeing the entire right hand side of the pinout table...

Wonder if my head pulled a trick on me or if you changed the picture in your post?

[jbiplane]

That is almost magical intuition, when I actually missed seeing the entire right hand side of the pinout table...

Wonder if may head pulled a trick on me or if you changed the picture in your post?
Yes I changed the picture to dont mess other readers. Thanks again for error you pointed. It is first version of datasheet. Complete user manual should be ready soon and probably ~20 pages would be enough.

BTW we have pressure and themperture sensors of ambient air inside of light version of SmartEMS to decrease number of exernal wires. We have variant of throttle body with flat surface to fix most of EFI hardware on. So carburetor could be easily and paintless replaced by EFI. Only fuel pump with wires go to fuel tank and crankshaft position sensor near geared wheel on crankshaft.

[Jannem]

Yes I changed the picture to dont mess other readers. Thanks again for error you pointed. It is first version of datasheet. Complete user manual should be ready soon and probably ~20 pages would be enough.

BTW we have pressure and themperture sensors of ambient air inside of light version of SmartEMS to decrease number of exernal wires. We have variant of throttle body with flat surface to fix most of EFI hardware on. So carburetor could be easily and paintless replaced by EFI. Only fuel pump with wires go to fuel tank and crankshaft position sensor near geared wheel on crankshaft.
Seems like a cool product. I think for the racers couple of extra inputs and outputs similar to Ignitech race ignition could be a usefull add on.
Another cool one would be ignition retard map based on deto and tps sensor voltage. Or an auto retard function that aims for pre-determined deto sensor voltage.

[philou]

Hello Jbpilane,

The electrical connector and it provides ?

[SwePatrick]

Would you like to share more information about the engine ?
I'm very interested about your project. Great power and a lot of revs !

Hello.

No further progress has been done since the 35.2hp dyno run.

It is an Minarelli AM6 engine with a 'Roost Havoc 98' cylinder.
Bore stroke is 52/46mm

Keihin carb copy, 34mm
Vforce 3
Homebuilt pipe.
E85 fuel(at this time, will be methanol later on)

https://www.speed-factory.net/media/image/10/33/bb/tuningkit-roost-havoc-95cc-fur-minarelli-lc-6559-rst-h16-00_900x600.jpg

[jbiplane]

The electrical connector and it provides ?

Salut philou

Basic connector yes, wire harness and other components can be added, we can supply complete kits.

To get the best results with 2-strokes it is recomended to use wideband 02 sensor + Dyno for all setting.

[husaberg]

jbiplane, thankyou.

I've been using the NZ made Link ECU. Used it on my Kawasaki crankcase/transfer port injected twostroke (shown in the picture, 2008) and also on the first B port TPI twostroke, YZ250 (2012)
This next development requires twin throttle control, detonation control and input sampling. The Link suits my needs for the moment.
Here you go Flet
336055

KTM’s Transfer Port Fuel Injection
In this side view we see that as in any simple crankcase-charged two-stroke engine, the KTM's charge air first enters the crankcase through a one-way reed valve, and is slightly compressed there as the piston descends. When the moving piston's top edge uncovers the transfer ports that join crankcase and cylinder, the slightly compressed air in the crankcase jets into the cylinder on a looping path which offers minimum mixing of fresh charge and exhaust gas. Fuel injectors in the tops of the transfer ducts add fuel to the entering air streams
KTM’s Transfer Port Fuel Injection
In this side view we see that as in any simple crankcase-charged two-stroke engine, the KTM's charge air first enters the crankcase through a one-way reed valve, and is slightly compressed there as the piston descends. When the moving piston's top edge uncovers the transfer ports that join crankcase and cylinder, the slightly compressed air in the crankcase jets into the cylinder on a looping path which offers minimum mixing of fresh charge and exhaust gas. Fuel injectors in the tops of the transfer ducts add fuel to the entering air streams


336054


Here we see the engine from behind and can see two of its transfer ducts in section. They conduct compressed air up from the crankcase and into the cylinder. A fuel injector, mounted in the top of each of these transfer ducts, sprays fuel against the moving air, thereby achieving a high speed difference between fuel droplets and airflow. This breaks up the fuel droplets, increasing their total surface area so that they rapidly evaporate to result in an easily ignited mixture of air and fuel vapor in the cylinder. The injection of fuel is timed such that none of it can reach the cylinder's exhaust port before it closes.


Illustration by Jim Hatch




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[Juho_]

Hello.

No further progress has been done since the 35.2hp dyno run.

It is an Minarelli AM6 engine with a 'Roost Havoc 98' cylinder.
Bore stroke is 52/46mm

Keihin carb copy, 34mm
Vforce 3
Homebuilt pipe.
E85 fuel(at this time, will be methanol later on)
I've heard about that cylinder and seen some videos on youtube (zip stunter), seems like it has even more potential than I had thought.
Atleast there is a lot of blowdown and transfer area.

Have you done any more modifications for the crankcases than just ported to fit the cylinder and the reed valve (ktm sx 65 / tpr or stage6 version fits without modifications..but do not have quite enough reed area for that large carburetor)?
Not really sure if there would be any benefit modifying the reed valve angle (in stock condition the reed valve is aimed towards crankshaft)...but crankcase volume is something there must have been changed since it'll be quite small for 98cc cylinder capacity.

[Flettner]

2012, YZ250. Took KTM a while but they eventually caught up:msn-wink:

[husaberg]

2012, YZ250. Took KTM a while but they eventually caught up:msn-wink:

Well they did have to translate it into sausage speak, and then figure out how you did it without wearing lederhosen.
Due to KTM not coming forward with the patents I would suggest it is Rotax that holds it and KTM is using it under licence.
Rotax do have a similar looking patent as I pointed out ages ago.
https://patents.google.com/patent/US20020011223

[Flettner]

Close but no cigar, injectors are angling into the cylinder with this patent. where as with the product they now sell the injectors clearly fire back down the B transfer ports toward the incoming air, just like our YZ.
I don't think they show a patent because they can't, the technology has been 'free to air' (prier knowledge) since early 2013, on the bloody internet for all to see. The firing down the transfer port toward the incoming air from the crankcase is the key. Somewhere to store the extra fuel when transfer port open/flow time is not as long as injector on time. This also helps furnish the A port with fuel higher up in the revs, on the pipe. The key is the injector position and the fact it fires back down the port. KTM know that now.

[philou]

It is an Minarelli AM6 engine with a 'Roost Havoc 98' cylinder.
Bore stroke is 52/46mm

Keihin carb copy, 34mm
Vforce 3

Minarelli sheet6 hase a ridiculous crankcase volume and little material to enlarge.

how did you do to install vforce reed valve ?

32Hp gearbox 6 speed and 6 false neutral :killingme

[Muhr]

Hello.

No further progress has been done since the 35.2hp dyno run.

It is an Minarelli AM6 engine with a 'Roost Havoc 98' cylinder.
Bore stroke is 52/46mm

Keihin carb copy, 34mm
Vforce 3
Homebuilt pipe.
E85 fuel(at this time, will be methanol later on)




Hats off to V Force for 34hp at 16400rpm obviously no reed floting

[Frits Overmars]

Hats off to V Force for 34hp at 16400rpm obviously no reed flotingMaybe the reeds can't be bothered to close at 273 Hz. With the right combination {crankcase volume + inlet duct diameter + inlet duct length} they won't need to :D.

[SwePatrick]

I've heard about that cylinder and seen some videos on youtube (zip stunter), seems like it has even more potential than I had thought.
Atleast there is a lot of blowdown and transfer area.

Have you done any more modifications for the crankcases than just ported to fit the cylinder and the reed valve (ktm sx 65 / tpr or stage6 version fits without modifications..but do not have quite enough reed area for that large carburetor)?
Not really sure if there would be any benefit modifying the reed valve angle (in stock condition the reed valve is aimed towards crankshaft)...but crankcase volume is something there must have been changed since it'll be quite small for 98cc cylinder capacity.

We run 1.28 in compressionratio in crankhouse, so yes it has been ported quite some.
The reedvalve suprisingly is made for AM6, so it is quite small.
We have plans of taking a CR85 V-force and and use that, i also think that the reed as used in the 35.2hp dyno is stretched to its limit, and then some ;)
They had to run without the stuffer, with the stuffer mounted it was a huge powerloss.

[SwePatrick]

how did you do to install vforce reed valve ?



Just bolted it on ;)
But it needed a spacer also to enlarge crankhouse.

[SwePatrick]

Hats off to V Force for 34hp at 16400rpm obviously no reed floting

When stumbeling into a certain combo, reed is actually better then disc to let it rev high and still having some chance of jetting carb correctly for low speeds.
Frits mentioned some parameters.
I often calls it 'standing wave'.
When reaching this the engine just becomes a combustion chamber for the pipe, that is acting like a pulsejet ;)

btw, 35.2hp not 34.

Some Dutch guy has dynoed above 36hp(can´t remember exact number, but is was above 36hp) with a Roost98, this with a boyesen KX85 reed.
The later Roost 100 flangemount cylinder is close to 40hp unported, HK tuning in Germany says he has dynoed above 41hp, but i´m not trusting that fully.

[Muhr]

When stumbeling into a certain combo, reed is actually better then disc to let it rev high and still having some chance of jetting carb correctly for low speeds.
Frits mentioned some parameters.
I often calls it 'standing wave'.
When reaching this the engine just becomes a combustion chamber for the pipe, that is acting like a pulsejet ;)

btw, 35.2hp not 34.

Some Dutch guy has dynoed above 36hp(can´t remember exact number, but is was above 36hp) with a Roost98, this with a boyesen KX85 reed.
The later Roost 100 flangemount cylinder is close to 40hp unported, HK tuning in Germany says he has dynoed above 41hp, but i´m not trusting that fully.

I your case then deliver between 266-274HZ should speak against any standing waves teori?
In the case with 41hp, in the old good times, Vortex RVA delivered 38hp out of box with 3 transfer ducts and 177 ° exhaust, so why not.:Punk:

[Juho_]

We run 1.28 in compressionratio in crankhouse, so yes it has been ported quite some.
The reedvalve suprisingly is made for AM6, so it is quite small.
We have plans of taking a CR85 V-force and and use that, i also think that the reed as used in the 35.2hp dyno is stretched to its limit, and then some ;)
They had to run without the stuffer, with the stuffer mounted it was a huge powerloss.
The CR85 v-force reed valve might require quite a lot grinding, because it's wider than your current reed valve.
I'm using a stock CR85 reed valve on my Minarelli AM6 motor (55cc). Previously used TPR v-force reed valve, slight increase in power above 11,000rpm.
Not sure if the reeds thickness is even close to what they should be...should try and test some day.

If the v-force reed valve is even wider, the crankcase might require some welding to have enough material.
CR85 reed valves do fit to Derbi (EBS050) crankcase quite easily, with only minor modifications.

Also, I would suggest a Mikuni TM or TMX series carburetor.
I got my motor work a lot better everywhere, and more power compared to PWK copy carburetor (modified).

[SwePatrick]

The CR85 v-force reed valve might require quite a lot grinding, because it's wider than your current reed valve.
I'm using a stock CR85 reed valve on my Minarelli AM6 motor (55cc). Previously used TPR v-force reed valve, slight increase in power above 11,000rpm.
Not sure if the reeds thickness is even close to what they should be...should try and test some day.

If the v-force reed valve is even wider, the crankcase might require some welding to have enough material.
CR85 reed valves do fit to Derbi (EBS050) crankcase quite easily, with only minor modifications.

Also, I would suggest a Mikuni TM or TMX series carburetor.
I got my motor work a lot better everywhere, and more power compared to PWK copy carburetor (modified).

It isn´t sadly enough my engine, so i cannot force him to use Mikuni, but i can ask him to.
He doesn´t like them, and later on as it will be running methanol, the carb almost doesn´t make any differences(my own experiances)
Just enough airflow, then fuel is secondary to that, as almost all carbs doesn´t do the job very good, with that much fuel in the air.

The engine is 'welded' so one can grind out material if needed for bigger reed.

But i want to try the boyesen KX85 reed as it might do the trick without having to grind.

[SwePatrick]

I your case then deliver between 266-274HZ should speak against any standing waves teori?
In the case with 41hp, in the old good times, Vortex RVA delivered 38hp out of box with 3 transfer ducts and 177 ° exhaust, so why not.:Punk:

Crank or rear wheel?

Standing wave can occur at almost any frequenzy, just study 4th order bassbox ;)
Not to say that the engine has that frequenz, but as a statement that this is very dynamic, and as i said, 'stumbeling'.
Nothing is calculated in the reed.
One almost cannot calculate a reedvalve as the speeding air acts as a spring also, and by that disturbs all calculations.
Calculate a reed at stationary air inside/outside the cage, fine! i can recognize that.

One just has to rape the laws of theory sometimes to get an 'aha' moment.

[Norman]

Close but no cigar, injectors are angling into the cylinder with this patent. where as with the product they now sell the injectors clearly fire back down the B transfer ports toward the incoming air, just like our YZ.
I don't think they show a patent because they can't, the technology has been 'free to air' (prier knowledge) since early 2013, on the bloody internet for all to see. The firing down the transfer port toward the incoming air from the crankcase is the key. Somewhere to store the extra fuel when transfer port open/flow time is not as long as injector on time. This also helps furnish the A port with fuel higher up in the revs, on the pipe. The key is the injector position and the fact it fires back down the port. KTM know that now.

I agree, reading through the 2002 patent they are close but they did not at the time really catch and understand how to do it in your elegant way. Very very good. The way they express themselves in their patent I do not think your solution will intrude their patent.

[Muhr]

Maybe the reeds can't be bothered to close at 273 Hz. With the right combination {crankcase volume + inlet duct diameter + inlet duct length} they won't need to :D.

Yes, maybe V-force was before you with a finished product without knowing about it.:second:


Crank or rear wheel?

Standing wave can occur at almost any frequenzy, just study 4th order bassbox ;)
Not to say that the engine has that frequenz, but as a statement that this is very dynamic, and as i said, 'stumbeling'.
Nothing is calculated in the reed.
One almost cannot calculate a reedvalve as the speeding air acts as a spring also, and by that disturbs all calculations.
Calculate a reed at stationary air inside/outside the cage, fine! i can recognize that.

One just has to rape the laws of theory sometimes to get an 'aha' moment.


Can't remember but it was direkt drive so.

"4th order bassbox" do you mean an audio speaker?

[SwePatrick]

Yes, a speaker =)
Many kartdynos are testing on the crank.

However!
36.2hp/15800rpm today, but.... Rod broke.
Engine is junk. =(

[Frits Overmars]

maybe V-force was before you with a finished product without knowing about it.:second:I doubt that Muhr. I don't know when Tassinari started producing its Vforce reeds, but I do know that my first 24/7 prototype dates from the previous millennium :first:.
336062

Joking apart, I think it's possible that a conventional reed starts behaving like a 24/7 inlet when the engine frequency rises above the reed's natural frequency,
but it will still offer a lot of flow resistance. Better swing the reeds out of the way altogether.

[Muhr]

I doubt that Muhr. I don't know when Tassinari started producing its Vforce reeds, but I do know that my first 24/7 prototype dates from the previous millennium :first:.
336062

Joking apart, I think it's possible that a conventional reed starts behaving like a 24/7 inlet when the engine frequency rises above the reed's natural frequency,
but it will still offer a lot of flow resistance. Better swing the reeds out of the way altogether.

I couldn't resist!:D
Think you are right. the question is just how efficient it is?
Maybe I can get a picture of it in the future, maybe even 24/7 !? Would be fun.

[jonny quest]

Vforce came out right around 1990. I had done some of the early prototype testing for him.

[DoldGuy]

2012, YZ250. Took KTM a while but they eventually caught up:msn-wink:

Flettner,

Could you illustrate how the A Port & the Boost Port are fed from just the single injector in the B Port? Would there be any benefit having additional injectors in the A Ports?

[jasonu]

Close but no cigar, injectors are angling into the cylinder with this patent. where as with the product they now sell the injectors clearly fire back down the B transfer ports toward the incoming air, just like our YZ.
I don't think they show a patent because they can't, the technology has been 'free to air' (prier knowledge) since early 2013, on the bloody internet for all to see. The firing down the transfer port toward the incoming air from the crankcase is the key. Somewhere to store the extra fuel when transfer port open/flow time is not as long as injector on time. This also helps furnish the A port with fuel higher up in the revs, on the pipe. The key is the injector position and the fact it fires back down the port. KTM know that now.

Email them. You might get a free t shirt.

[F5 Dave]

Be orange though

[Flettner]

They know who I am, Rodney O'Connor did an article on the EFI YZ middle 2013 for Kiwi Rider. He used to work at KTM, Austria before this. He said he had seen the EFI that they were working on (direct injected, Orbital) and had a friend working in that department, still had correspondence with KTM. I do believe he sent pictures and information on the YZ project back to KTM. He certainly did send them the Kiwi Rider magazine, he told me.
That was about the time KTM had come up against a brick wall with their development.
You can't tell me they didn't copy our YZ project. And they don't have to pay any patent royalties, win win for KTM.
But that does mean the likes of TM can also use this system, nothing stopping TM. We have been in contact.

You know it gets even murkier, I had heaps of pictures and information on TSM web site with in depth explanations of how I designed and built both the F9 and the YZ, Termed it Transfer Port Injection (TPI) and pointed out how the next step was pressure sampling of crank case ( I believe that is what KTM are doing now) . This TSM web site was hacked about this time and completely fucked. It's only just been restarted again years later. Lots missing. Coincidence? Who knows, but you have to wonder.

I do believe this TPI is just breathing space technology, they needed somthing quick and cheap for Euro4.
KTM are not to worried about protecting this technology as shortly it will be out dated anyway. If they want to keep running twostroke's they will need somthing way more sophisticated than TPI. KTM are either working on this now or this is the end of the road for the twostroke. Stick to fourstroke s until electric comes of age. When? when there is a leap forward in battery energy storage, getting better but we are not there yet.

[ken seeber]

I do believe this TPI is just breathing space technology, they needed somthing quick and cheap for Euro4.
KTM are not to worried about protecting this technology as shortly it will be out dated anyway. If they want to keep running twostroke's they will need somthing way more sophisticated than TPI. KTM are either working on this now or this is the end of the road for the twostroke. Stick to fourstroke s until electric comes of age. When? when there is a leap forward in battery energy storage, getting better but we are not there yet.

Well, a couple of comments:

1. In Vietnam went chasing TZ350's Thomas (see Page 1 of ESE) but couldn't find him. TeeZee ???? Maybe he was just out for the day, but certainly industrious.

336067336068336069

2. In Saigon, a city of 10,000,000 there are 8,000,000 bikes. In terms of 2 strokes, out of all that, I only saw a couple of early Vespas, a Lambretta and a Simson. However, there are a lot of elec bikes, mainly smaller stuff though.

336070336071336072

So, we'd better get a move on with emission and fuel consumption reductions.

[SwePatrick]

My new cylinderproject is coming along nicely.

New 6082 liner installed.
Bored it out yesterday to fit the piston, 66,37mm, the remaining up to 66.41 i´ll let the nikasilplaters do.

Now i can put engine together and set the timings perfectly before plating.
There are still some holes to drill into the water jacket.

336077

[Juho_]

Yes, a speaker =)
Many kartdynos are testing on the crank.

However!
36.2hp/15800rpm today, but.... Rod broke.
Engine is junk. =(
Did the rod itself actually break ?
Do you know what crankshaft or conrod was used?

YZ80 rods have been very reliable on my motors.
From mitaka / prox they are also very cheap.
90 and 94mm lengths available.
18mm big end pin.

[SwePatrick]

Did the rod itself actually break ?
Do you know what crankshaft or conrod was used?

YZ80 rods have been very reliable on my motors.
From mitaka / prox they are also very cheap.
90 and 94mm lengths available.
18mm big end pin.

Yes, it snapped off just under the wristpin.
The crank was a Parmakit, myself think it isn´t top notch.
And, engine has been revved hard also in some pulls on dyno by mistake.

336096

I think it´s actually fully repairable and the crank is almost unhurt, change of a rod to a high end rod(we have got a Samarin laying on a shelf)

[Juho_]

Yes, parmakit does not really have a good reputation on their products..

It's quite unusual to break the rod, but revving more than 17,000rpm(?) is also unusual with such as heavy piston.

The cylinder looks like it survived better than would expect after breaking the rod.
Even tho it requires 'some' welding and replating. :D

[wobbly]

Just to clarify the theory.
4th order bandpass bass box theory has nothing to do with intake resonance.
In speaker terminology 4th order refers to the number of reactive elements in the system that produce a very high rate of slope ( amplitude reduction ) each side of a chosen frequency.
But in an intake system when we are talking about the harmonic " order " this is the fundamental frequency of the intake ( dictated by rpm/60=Hz ) divided by the number of times
the active wave traverses the tuned length.
Anything over the 3rd harmonic has so little energy it is pretty much useless, but the correct tuned length for lower orders ( although higher in amplitude ) usually make the intake way too long to actually fit on an engine.

[peewee]

have got a Samarin laying on a shelf)

i tried email to that guy and nobody responded. i cant call because i dont know if they understand english. eventually i just had to buy prox rods

[Grumph]

i tried email to that guy and nobody responded. i cant call because i dont know if they understand english. eventually i just had to buy prox rods

Similar experience here. Don't know how they do business.

[husaberg]

i tried email to that guy and nobody responded. i cant call because i dont know if they understand english. eventually i just had to buy prox rods


Similar experience here. Don't know how they do business.
Source them out of Roffe.
http://www.pvlsverige.se/vrm/index/indexeng.html

or Emot
http://www.emot.nl/

[philou]

Pictures of crankcase with vforce3 85 Cr ?

Samarin is very good product, unfortunately very difficult to get even for professional :(

[SwePatrick]

Just to clarify the theory.
4th order bandpass bass box theory has nothing to do with intake resonance.
In speaker terminology 4th order refers to the number of reactive elements in the system that produce a very high rate of slope ( amplitude reduction ) each side of a chosen frequency.
But in an intake system when we are talking about the harmonic " order " this is the fundamental frequency of the intake ( dictated by rpm/60=Hz ) divided by the number of times
the active wave traverses the tuned length.
Anything over the 3rd harmonic has so little energy it is pretty much useless, but the correct tuned length for lower orders ( although higher in amplitude ) usually make the intake way too long to actually fit on an engine.

My statement was just a hint to activate the brain and think outside the box.
Air is a spring wherever it is, so yes they have something in common ;)

[SwePatrick]

i tried email to that guy and nobody responded. i cant call because i dont know if they understand english. eventually i just had to buy prox rods

You mean you mailed samarin?

Yes they don´t answer mails :(

One has to buy from a reseller.

[Peter1962]

You mean you mailed samarin?

Yes they don´t answer mails :(

One has to buy from a reseller.

Why not send your request to emot ? I am sure you will get a swift answer.

[SwePatrick]

Why not send your request to emot ? I am sure you will get a swift answer.

I have no problems getting the rods i need.
Either through VRM.se or an another reseller
You must have misunderstood me? ;)

We already have a replacement rod in storage, the topnotch model from samarin.

[katinas]

Tree days testings on the road with isolated transfers ducts and standard type NS engine.
Tested same cylinder, just with and without separation parts for comparison ( 30 min between changing)

0 - 4000 rpm - same power.

4000 - 8000 rpm - "isolated" more noisy (from carb) less power.

From 8000 rpm pipe is on and power goes up in similar way with both type until 11000 rpm , but from this point similarities ended. Std engine power gradually goes down to 13000 rpm.

"Isolated" revs with power until 12500 rpm and then suddenly goes down to 13000 rpm. Never felt before, such a wide power band from this NS cylinder with such moderate Ex/Trans/Reed area.

Tested just in 1-2-3 gears, so more clear would be after race track testing in all gears. But first riding was very interesting, really did not expect.

[Muhr]

Tree days testings on the road with isolated transfers ducts and standard type NS engine.
Tested same cylinder, just with and without separation parts for comparison ( 30 min between changing)

0 - 4000 rpm - same power.

4000 - 8000 rpm - "isolated" more noisy (from carb) less power.

From 8000 rpm pipe is on and power goes up in similar way with both type until 11000 rpm , but from this point similarities ended. Std engine power gradually goes down to 13000 rpm.

"Isolated" revs with power until 12500 rpm and then suddenly goes down to 13000 rpm. Never felt before, such a wide power band from this NS cylinder with such moderate Ex/Trans/Reed area.

Tested just in 1-2-3 gears, so more clear would be after race track testing in all gears. But first riding was very interesting, really did not expect.
The first thing that come to my mind is less blow back because of higher drag on the top, in the isolatet version. What would happen if you gave it a little more blow down. And less power on midrange due to drag.:scratch:

[mattology]

Here you go Flet
336055


336054






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never before has pissing in the wind seemed to have such great results

[katinas]

The first thing that come to my mind is less blow back because of higher drag on the top, in the isolatet version. What would happen if you gave it a little more blow down. And less power on midrange due to drag.:scratch:

Maybe, I need to try rounded piston edge and then little more blow down. This cylinder and piston is for testings, so I don't much worry about mistakes.
With isolated version, from 11000 to 12500 rpm its like the power not much rising, but more like extension in rpm range. And maybe, little cooler mix help.

Isolated version, like conventional, depends on pipe. Tried four different pipes and engine reacts like std. just longer power extension.
One pipe made from old NS exhaust with 40mm stinger and R6 muffler - on the road it revs to 13000 rpm, but just with half of previous power ( add winter static test with this pipe- for fun https://youtu.be/RlQ83PNcsg0 )

[Grumph]

never before has pissing in the wind seemed to have such great results

It would appear to be pissing INTO the wind - which most of us learn not to do at an early age....

[TZ350]

35.2hp dyno run.

It is an Minarelli AM6 engine with a 'Roost Havoc 98' cylinder.
Bore stroke is 52/46mm

Keihin carb copy, 34mm
Vforce 3
Homebuilt pipe.
E85 fuel(at this time, will be methanol later on)

https://www.speed-factory.net/media/image/10/33/bb/tuningkit-roost-havoc-95cc-fur-minarelli-lc-6559-rst-h16-00_900x600.jpg


Minarelli, Aprilia AM6 and Scooter aftermarket cylinders are not very common here in New Zealand so I don't know much about them.

I would love to know more about the Roost Havoc cylinder, its exhaust and transfer timings and the pipe that you used.

If I knew what to look for I guess it would be pretty easy to buy a cylinder or two and pipe over the net. I would love to try one on my rotary valve engine.

And if anyone knew of a current performance 50cc cylinder kit and pipe I would love to hear about those too.