ESE's works engine tuner

[richban]

Im still quite dismayed that after all this, FXR 1fucking50s are still the standard.

Don't forget the CBR's. They go good to. Other people are working to develop there engine's as well. Its not just the 2 stroke peeps on this thread that are making advances with there engines. Bar gets moved every year.

[kel]

At this stage, it remains to be seen, as even when Teezees bike was peddled by a featherweight rider, it wasn't winning anything before expiring. Although, when the same rider was riding a bike with substantially less power it by all accounts it cleaned up.

Im still quite dismayed that after all this, FXR 1fucking50s are still the standard.

Feather weight part is right, not sure about the cleaning up though. I managaed two 1st a 2nd and a 3rd (and a couple of DNF's) on the FXR during the north island series, managed a 3rd first time out on TZ's bike and suffered no race DNF's. With a couple of chassis mods and a dialed back ignition curve the bike has the potential to win ever time it lines up.
ps Why be dismayed by the mighty FXR, they're true race bikes with handling to be envied (FXR for sale drop me a PM :cool:)

[jasonu]

PS - if ANYONE can do a 125 Aircooled with 24mm carb and make anything like 30 Hp at 10500, then its here in writing - free blowys for life.


.

TeeZee has managed to make 31 hp with his old 125cc air cooled engine from the 70's and with some development I expect he will get it reliable too.

.

Where/when/how will TeeZee cash in on this huge win and who will be giving the blowys...???

[bucketracer]

263372

Nope TeeZee can't claim the prize. 31ps at 12,250 rpm with 18Nm (13.3ft/lbs) and 28.8ps at 11,750 rpm with 17.3Nm (12.8ft/lbs) and a good power spread.

[F5 Dave]

. . PS - if ANYONE can do a 125 Aircooled with 24mm carb and make anything like 30 Hp at 10500, then its here in writing - free blowys for life.
Hey I'm not trying to cash in on the offer, but I think a dose of Nitrous would do it.

[bucketracer]

Hey I'm not trying to cash in on the offer, but I think a dose of Nitrous would do it.

Funny you should say that, but we have dynoed a F5 here that was fitted with Nitrous

[F5 Dave]

263372

Nope TeeZee can't claim the prize. 31ps at 12,250 rpm with 18Nm (13.3ft/lbs) and 28.8ps at 11,750 rpm with 17.3Nm (12.8ft/lbs) and a good power spread.

Wish youse guys would post curve with 0rpm as datum to give a sense of perspective. Yes I know you never run down there, but makes curves relative to each other rather than an arbitary starting point.

[F5 Dave]

Funny you should say that, but we have dynoed a F5 here that was fitted with Nitrous
My first draft of that named him, but I changed it. Curve confused me when I saw it, just didn't believe it was possible.

[wobbly]

125 Aircooled with 24mm carb - bucket rules, is the challenge.
I will gladly suck the chrome off anyones towball that can do anywhere near 30 Hp at 10500 - im bloody good at this shit and wouldnt even try - doomed to failure.
That requires around 35 crank Hp, and equals 11.9Bar 0r 175psi BMEP at 10,500 - dreaming , as at that level you are screwing the tuning down real tight and the
perceived advantage of any power-band width has just gone west.
Mr Physics wins again and I keep my dignity.

[husaberg]

I will gladly suck the chrome off anyones towball that can do anywhere near 30 Hp at 10500 - im bloody good at this shit .
http://www.petermunro.co.nz/images/towmaster_tow-bars-4x4.jpg


PS - if ANYONE can do a 125 Aircooled with 24mm carb and make anything like 30 Hp at 10500, then its here in writing - free blowys for life.

I would just like to have it on Record whist i don't doubt your talent Wob"I have never built and I have no intention to, Ever to build or ever attempt to build a 125 AC 2 stroke with a 30HP at 105000".:laugh:

Whist the suggestion at changing primary drive, i could make no sense of. It did make me wonder if one was to make their own engine one of the things that always scares me is primary drive.
1 because custom gears are bloody expensive.

2 cause they have to be perfect. So using another set of ready made gears is problematic for the amateur.

I have seen in a quite a few right ups from seemingly reputable sources that chains primaries are more efficient.

Now don't get me wrong, i come from a history of British shiter's with chain drives so i am definitely not a fan.
But in the early classic movement the chains were replaced by Belt primary's for a reputed gain of 1.5hp to 2 HP per 50HP and no oil on wheels etc longer life etc quieter ...

So if this is the case why aren't Real COMPETITION bikes running around with Belt drive primaries. As if it were true there would be an easy few HP there?:scratch:

[twotempi]

Wobbly - To be honest your offer of a reward for a 3o HP @ 10500 engine is a powerful incentive for not trying !!:laugh::laugh:

[TZ350]

Personally I was a bit disappointed to hear the carb restriction was being lifted. Not because I'm afraid of being beaten, I'm used to that, but because I don't like seeing rule changes that aren't needed.

As for how fast Richban's bucket is, and what size, you only have to watch the videos he posted and see Fish dealing to him and Andrew on his Longchin to realise it isn't all about horsepower.

I've started on my new cylinder. Not totally sure where it will end but I'm aiming to break 30, and I still won't win.:crybaby:

I don't think Speedpro or I are under any allusions as we have known for a long time that handling and riding and hp alone won't win races but it sure is fun to make and within the restrictions of the F4 rules, we havent been doing to badly at it.

If you look back through my dyno graphs you can see a trend of increasing power spread with increasing rpm.

My 30+ hp engine in fact has a wider spread of power than the engine Av used to clean up on at Tokoroa and Te Puke.

[Kickaha]

1 because custom gears are bloody expensive. $500 for the two primary gears on a GN

[F5 Dave]

ie: several x more than the bike was worth (depending if the tank was full or not):bleh:

[husaberg]

Personally I was a bit disappointed to hear the carb restriction was being lifted. .:crybaby:
Say what i am guessing it was an unfounded rumor?


$500 for the two primary gears on a GN
I actually remember you saying something in a PM i can remember why you would need Them though?
Not actually the point of the question though. But good to know as i was talking a High HP "race" engines and not GN125's. Was it to fit in the Dr350 crank?


Whist the suggestion at changing primary drive, i could make no sense of. It did make me wonder if one was to make their own engine one of the things that always scares me is primary drive.
1 because custom gears are bloody expensive.

2 cause they have to be perfect. So using another set of ready made gears is problematic for the amateur.

I have seen in a quite a few right ups from seemingly reputable sources that chains primaries are more efficient.

Now don't get me wrong, i come from a history of British shiter's with chain drives so i am definitely not a fan.
But in the early classic movement the chains were replaced by Belt primary's for a reputed gain of 1.5hp to 2 HP per 50HP and no oil on wheels etc longer life etc quieter ...

So if this is the case why aren't Real COMPETITION bikes running around with Belt drive primaries. As if it were true there would be an easy few HP there?:scratch:

[Yow Ling]

I have seen in a quite a few right ups from seemingly reputable sources that chains primaries are more efficient.

Now don't get me wrong, i come from a history of British shiter's with chain drives so i am definitely not a fan.
But in the early classic movement the chains were replaced by Belt primary's for a reputed gain of 1.5hp to 2 HP per 50HP and no oil on wheels etc longer life etc quieter ...

So if this is the case why aren't Real COMPETITION bikes running around with Belt drive primaries. As if it were true there would be an easy few HP there?:scratch:

Modern bikes use mass centralisation , stacked gearboxes etc to deliver a compact engine, using a belt primary necissitates a big gap between engine output shaft and gearbox input shaft to allow the belt to wrap around the small belt sprocket, this allows more teefs to carry the load

[husaberg]

Modern bikes use mass centralisation , stacked gearboxes etc to deliver a compact engine, using a belt primary necissitates a big gap between engine output shaft and gearbox input shaft to allow the belt to wrap around the small belt sprocket, this allows more teefs to carry the load

Too true but the packaging issues are going to be limited by the size of the crankshaft anyway but i do see your point.
Pre-unit construction engines and the bits unit ones as well obviously had lots of room
http://www.chris-knight-mcs.co.uk/acatalog/Cluch%20Belt%20Conversion%20Triplex.JPGhttp://www.britcycle.com/products/images/46503001.jpghttp://www.britcycle.com/products/images/QPD1.jpg
Actually was the Swissauto Geardrive or Belt drive WOB?Hindsight (and attachment viewing) i think it was the Yank V4 I think the swissauto had only a water pump belt drive like a f3 car.

[dinamik2t]

Ohh look page 500. 3rd bump then I give up

Dave, I have no experience on the matter, but I have a few notes on some pistons/wrist pins, which include the inner distance of piston sides (wrist pin area) and the wrist pin width. I avoided giving you those number, since it's no real reference nor racing specs (not necessarily).
It's not much, but it might help as examples of what a manufacturer would use - which, in most cases, is safe at least. I 'll have them tonight when I get back home. If I forget, do send me a reminder PM!

[Grumph]

Husqvarna of all people did a 50cc moped power unit which used a belt primary - which looks to be about 30mm wide.

A belt primary set for a British single is actually dearer than making up a primary gear set...but it does include the clutch too.

[bucketracer]

Wish youse guys would post a curve with 0rpm as datum to give a sense of perspective

263376

There you go ......

[husaberg]

263376

There you go ......Oh that clears that up nicely:laugh:

[dinamik2t]

263376

There you go ......

That's double the power of TeeZee!

[bucketracer]

I have shown several dyno runs with similar peak power, just thousands of rpm less, and over a far wider "band"


Similar power, wider power band, but were they a similar engine to TeeZee's high 20's to 30+ hp 125cc rotary valve air cooled engines running a 24mm carb. Could you post something because I can't find it.


i can't claim responsibility for this engine, but (so far) the highest power i have seen from this capacity with a 24mm carb is this series of runs.

263379

I looked through all your posted dyno graphs, and this is the only one where the text refers to anything that's similar to TeeZees engines.

And that graph was posted less than 3 years ago.


125cc (123.67cc to be exact) Vespas have been putting out more than 28PS for at least 5 years.
OK, I am confused, ....... please help us out here. http://www.kiwibiker.co.nz/forums/images/smilies/scratch.gif

[F5 Dave]

Dave, I have no experience on the matter, but I have a few notes on some pistons/wrist pins, which include the inner distance of piston sides (wrist pin area) and the wrist pin width. I avoided giving you those number, since it's no real reference nor racing specs (not necessarily).
It's not much, but it might help as examples of what a manufacturer would use - which, in most cases, is safe at least. I 'll have them tonight when I get back home. If I forget, do send me a reminder PM!
Thanks, it would give me some measurement of what is possible to run.

[SS90]

Similar power, but were they a similar engine to TeeZee's high 20's to 30+ hp 125cc rotary valve air cooled engines running a 24mm carb.





I looked through all your posted dyno graphs, and this is the only one where the text refers to anything that's similar to TeeZees engines.

And that graph was posted less than 3 years ago.


OK, I am confused, ....... please help us out here.

It is 2012.......

Anyway, here is a blank liner 55mm, simple to make, its possibly time your Father made one. I believe GP125 cylinders are "cast in", so it will take a bit of machining.

Perhaps even a new Skin is in order? you can make one from solid stock if need be.

I have used 54mm 55mm and 56mm pistons making my cylinders (small end sizes are a pain in the arse for these rods), as sometimes you have to use what pistons are available.

The best cylinder you can buy uses a 54mm Vortex Piston, high quality 56mm pistons are available for a full retail of the eqivilent of $NZ100, which ends up slighly over 125cc, and the Vertex are at least double that.

28PS, 54mm bore, yea..... that came out about 5 years ago. And you can bet there was a few clever guys doing their own stuff before that.

[SS90]

Not sure where you got that from, maybe a quote or two would be handy.



There is no doubt about how impressivly Av cleaned up at Tokoroa and then again at Te Puke on her RS/GP125. The bike was prepaired by Chambers and based on TeeZee's work, the engine layout followed TeeZee's ideas posted earler.

I don't think anyone doubts that more hp in her hands will be devistating.

Erm, your second quote maybe?

More power? I cant see how that is needed, given that from what I can ascertain, the winning bikes have just over 22 HP or so, and they are all making that power below 11,000 RPM (is there anyone with a power graph of the winning bikes?)

a 125 2 stroke can easily make that type of power, it is done every day.

[SS90]

125 Aircooled with 24mm carb - bucket rules, is the challenge.
I will gladly suck the chrome off anyones towball that can do anywhere near 30 Hp at 10500 - im bloody good at this shit and wouldnt even try - doomed to failure.
That requires around 35 crank Hp, and equals 11.9Bar 0r 175psi BMEP at 10,500 - dreaming , as at that level you are screwing the tuning down real tight and the
perceived advantage of any power-band width has just gone west.
Mr Physics wins again and I keep my dignity.

Im not saying that 30hp at 10,500 is required there Wobbly.

What is possible is say 22-25 HP at 10,500, and that, from my experience is not only feasable, but race winning as well.

Speedpro, from his recent posts in his thread is the most likely person to achieve this. If he runs his planned 192 degrees, and with the time area limitations of his single exhaust port, he will be limited to achieving power with a lower rpm ceiling, and with a pipe deigned accrdingly, he is going to have a grunter.

its nice to see 30 hp buckets, but it seems far less than that is required to win races.

Mind you, if someone was to get hold of a Cagiva Mito (7 speed model), sleeve that down to 100cc, and use the port map you used on Speedpros cylinder, along with that exhaust, you would in all likelyhood have the fastest bucket on the planet (as the fastest bucket in New Zealand is currently a 4 stroke 150, as races are won on lap times, not back straight speed)
I have often wondered why no one has really gone into expansion chambers in a big way on this thread.....

[Haufen]

"heaven on earth" how so?

Last time I checked (this afternoon) small frames are all 4 speed, and other than some short fourth manufacturers, you are limited to either an ET3, PK80 SS50 or Primavera übersetzung... Although the 50s had a "long fourth", and works well with certain set ups.

That's strange. There are dozens of other options. I don't want to get too offtopic here, so I will list a couple of gearing possibilities that come to my mind right now, and if you want to know more just contact me via PM.

Primary Ratios:
the ratios you mention are: 2,54 (ET3+Primavera), 2,86 (PK80) and probably 3,72 (SS90). Apart from these you can also get, for example, 2,34 (68/29), 2,56 (69/27), 3,00 (72/24). For all these straight cut primary gears there are aftermarket pinions available, usually one or two teeth apart from the standard pinion so you can make very small adjustments.

for 2,34 (68/29) there are pinions with 30, 28, 27 and 26 teeth giving a ratio of 2,26 / 2,43 / 2,52 / 2,62
for 2,56 (69/27) there are pinions available with 28, 26, 25 and 24 teeth, resulting in ratios of 2,46 / 2,65 / 2,76 / 2,88
for 3,00 (72/24) there are pinions available with 25, 23, 22 and 21 teeth, resulting in ratios of 2,88 / 3,15 / 3,30 / 3,45

and I am sure I still may have missed some combinations.

As far as the gears are concerned, amongst others, there is at least one five speed gearbox that is able to cope with serious horsepower. But as that is not a mass production thing and thus pretty expensive, let's concentrate on the traditional 4-speed gearbox.

Most commonly used is the following:
1. gear 58/10
2. gear 54/14
3. gear 50/18
4. gear 46/22

using aftermarket gears and christmas trees you have the following chioces (at least, I am not so sure if I am up to date on this)

1. gear 58/10, gears available with 56 / 55 / 54 teeth
2. gear 54/14 gears available with 56 / 55 / 52 teeth, christmas tree availabe with 13 teeth also
3. gear 50/18 gears available with 51 and 49 teeth, christmas tree available with 17 teeth (all can be combined), also 16 teeth tree available (don't know about compatibility)
4. gear 46/22, gears available 48 teeth, christmas trees available with 21(46), 21(47+49), 20(47), 19 (47), 18 (47), 20(46)

And there is even more. Heaven on earth, isn't it?



In F4 a 100cc 2-Stroke can be water cooled and have any size carb, a 125 must be air cooled and is restricted to a 24mm carb.

TeeZee has managed to make 31 hp with his old 125cc air cooled engine from the 70's and with some development I expect he will get it reliable too.

Casting your own cylinder is allowed and a pretty impressive thing to do. RGV250 cylinders have been sleeved down to 100. And TeeZee has looked at air cooling one too. RG400 cylinders are/were also popular.

Basically anything you make or can modify from a non-compitition engine is allowed.

I think you can be very happy with your regulations, as it looks like they allow for a great amount of freedom of choice without any setups / directions being superior to the rest. Too bad I am living on the other side of the planet, if I were in NZ, I'd surely take part. Are there any european 125cc two-stroke street bikes available in NZ, for example Aprilia RS125, or Cagiva Mito (Evo)?

And, by the way, this thread is a great read! I really like the attitude of sharing experience and helping each other which is present here :rockon:

[SS90]

That's strange. There are dozens of other options. I don't want to get too offtopic here, so I will list a couple of gearing possibilities that come to my mind right now, and if you want to know more just contact me via PM.

Primary Ratios:

and I am sure I still may have missed some combinations.

As far as the gears are concerned, amongst others, there is at least one five speed gearbox that is able to cope with serious horsepower. But as that is not a mass production thing and thus pretty expensive, let's concentrate on the traditional 4-speed gearbox.

Most commonly used is the following:
1. gear 58/10
2. gear 54/14
3. gear 50/18
4. gear 46/22

using aftermarket gears and christmas trees you have the following chioces (at least, I am not so sure if I am up to date on this)

1. gear 58/10, gears available with 56 / 55 / 54 teeth
2. gear 54/14 gears available with 56 / 55 / 52 teeth, christmas tree availabe with 13 teeth also
3. gear 50/18 gears available with 51 and 49 teeth, christmas tree available with 17 teeth (all can be combined), also 16 teeth tree available (don't know about compatibility)
4. gear 46/22, gears available 48 teeth, christmas trees available with 21(46), 21(47+49), 20(47), 19 (47), 18 (47), 20(46)

And there is even more. Heaven on earth, isn't it?






None of these are new (DRT was making crank gear "conversions" many years ago), the bottom line is that no matter which way you shuffle the cards, there are only 4 gears to play with (making layshafts is an expensive process, by any ones standards, although I have recently seen cheaper ones on offer)
5 speed conversions? I am yet to see one that can last the distance. The restriction of gear ratios is a constant thorn in your side, but it does force you to create engines with wide power spreads, which is always nice.

[Yow Ling]

I have often wondered why no one has really gone into expansion chambers in a big way on this thread.....

They have you just wernt looking. In fact your first rants were about how Thomases cousin stole the worlds best pipe design from your mate the pipe genius and that was why all asians could not be trusted ever again

[husaberg]

Erm, your second quote maybe?

More power? I cant see how that is needed, given that from what I can ascertain, the winning bikes have just over 22 HP or so, and they are all making that power below 11,000 RPM (is there anyone with a power graph of the winning bikes?)

a 125 2 stroke can easily make that type of power, it is done every day.


Similar power, but were they a similar engine to TeeZee's high 20's to 30+ hp 125cc rotary valve air cooled engines running a 24mm carb.



263379

ok, I am confused ....... please help us out here. http://www.kiwibiker.co.nz/forums/images/smilies/scratch.gif



I would have thought it was pretty obvious if you work in the industry see attached :facepalm:



But then again, you have Never worked in the industry....


That will be the problem. Maybe it also didn't have a Turbo like those pre 1956 2 strokes




I said ( possibly 1956, and issued a rider that I was not sure of the date), I would now go to say that it was "mid 60's" when several European manufacturers had Compressor's on 2 strokes.... Both driven of exhaust gas, or another power source.

Considering " exhaust gas powered turbines" where winning the Indy 500 in the early sixties, and running since before then) I fail to understand why it is so hard to accept that many factories where able to get working
examples of their own.....

I believe the badges are made in Vietnam.




I'll make a deal..... If Teezee finishes his Plenum....and posts PRINTED dyno graphs, as well as a video of the runs, I will post 5 pictures of an Austrian exhaust gas propelled turbine boosted engine and 3 pictures of a German exhaust gas propelled turbine boosted engine,( I am starting to see why the termsTURBO and SUPERCHARGE where brought into use in the English Vernacular ) before 1966.
.

[bucketracer]

TeeZee has already talked about sleeves, use Thread Tools and View Images to see them.

Anyone who thinks they can win races against the current crop of 20-23 hp FXRs with a low 20's hp 2-stroke is likely to be dissapointed.

[SS90]

TeeZee has already talked about sleeves, use Thread Tools and View Images to see them.

Anyone who thinks they can win races against the current crop of 20-23 hp FXRs with a low 20's hp 2-stroke is likely to be dissapointed.

Why? Has anyone actually tried?

41 hp 125 strokers used to whip 75hp 4 strokes all day long in formula 3, and there are plenty of 125 GP chassis that have found their way into buckets (daves fiddy is a perfect example), and in the grand scheme of things, that has bugger all power. It has won plenty against bigger more powerful engines. Darren Gosper had a fast one back in the day too (but if I remember right, a standard RG chassis)

[crazy man]

Why? Has anyone actually tried?

41 hp 125 strokers used to whip 75hp 4 strokes all day long in formula 3, and there are plenty of 125 GP chassis that have found their way into buckets (daves fiddy is a perfect example), and in the grand scheme of things, that has bugger all power. It has won plenty against bigger more powerful engines. Darren Gosper had a fast one back in the day too (but if I remember right, a standard RG chassis)who had these 75 hp f3 bikes? but agree 22-24 hp 2 stroke with a good bike set up and rider is all it needs to win gp's

[wobbly]

Some are forgetting NoMates RGV100/RS125 that had over 28 Hp some 7 years ago.
It won 3 straight bucket titles and was basically unbeatable - THEN became unreliable due to uncorrected wear on the bridge.
Anyone who was in the way got blasted on any short straight, or got ridden over the top of.
Fast 2T, fast chassis, maniac rider - no one got close unless he crashed.
The cylinder liner has been plated now, and it runs all day just fine - the rider is busy doing other stuff so it hasnt been out for some time.

SpeedPros new setup is for a few customers, not his own use - and I am doing the pipe layout to suit 192* and 12,000,so will be interesting to see how a low
20s 2T goes with good handling and riders.

[SS90]

who had these 75 hp f3 bikes? but agree 22-24 hp 2 stroke with a good bike set up and rider is all it needs to win gp's

Terry Fitzgerald had mid 70s (GsxR400) Andy Bolwell, Bredan Gere and John Lowther (all ZXR400's) had something similar, Chis Huddlestone had 68 (ZXR 400) and Adrian Main had 71hp (GSxR400)

But yea, as I am sure you are aware, Steve Ward had the measure of them all (most of the time), as did Glenn Hayward (even on his NX4 framed fiddler special) Jason Easton, Cam Horgan and quite a few others.

That was after Methanol was banned (boo), and before the 450 rule came in, where 80hp was the number for a big bore 400.

[Haufen]

None of these are new (DRT was making crank gear "conversions" many years ago), the bottom line is that no matter which way you shuffle the cards, there are only 4 gears to play with (making layshafts is an expensive process, by any ones standards, although I have recently seen cheaper ones on offer)
5 speed conversions? I am yet to see one that can last the distance. The restriction of gear ratios is a constant thorn in your side, but it does force you to create engines with wide power spreads, which is always nice.


This is getting exhausting. At first you mention a lack of primary gear ratios, then you tell me you knew all that. Same with the gear ratios. Now you complain about having only 4 gears. Next thing will be the 10 inch scooter wheels and tires? I don't get it - and I don't have to.

Fact is:

nowadays, everyone is able to go way faster on a Vespa than reasonable without running into problems concerning the number of gears, the availability of primary gear ratios, the spread between each of the 4 gears or the durability of the gearbox.

[SS90]

Some are forgetting NoMates RGV100/RS125 that had over 28 Hp some 7 years ago.
It won 3 straight bucket titles and was basically unbeatable - THEN became unreliable due to uncorrected wear on the bridge.


SpeedPros new setup is for a few customers, not his own use - and I am doing the pipe layout to suit 192* and 12,000,so will be interesting to see how a low
20s 2T goes with good handling and riders.

Im not forgetting it, far from it.

I recon, with the right pipe, frame and rider, based on what I am told, and see written here in regards to what bikes are winning, a mid 20's stroker in an RS chassis would walk away with it (and perhaps squash silly rumors that tuned 2 strokes are unreliable):shutup:

[SS90]

This is getting exhausting. At first you mention a lack of primary gear ratios, then you tell me you knew all that. Same with the gear ratios. Now you complain about having only 4 gears. Next thing will be the 10 inch scooter wheels and tires? I don't get it - and I don't have to.

Fact is:

nowadays, everyone is able to go way faster on a Vespa than reasonable without running into problems concerning the number of gears, the availability of primary gear ratios, the spread between each of the 4 gears or the durability of the gearbox.

Calm down schatzi!

I build small frames for a living.

Have you had the opportunity of tuning a 2 stroke with more than 4 available ratios? No matter how you shuffle the cards, that, and than alone, is what holds you back.

Even at Stokach, where blech roller quarter miles reach frightening speeds, or the once a year 2 laps of the Nurburgring, where the limit is pushed further still, if these engines had more available gear ratios, then we would be able to build engines with more power (just over a narrower RPm range)

[richban]

Some are forgetting NoMates RGV100/RS125 that had over 28 Hp some 7 years ago.
It won 3 straight bucket titles and was basically unbeatable - THEN became unreliable due to uncorrected wear on the bridge.
Anyone who was in the way got blasted on any short straight, or got ridden over the top of.
Fast 2T, fast chassis, maniac rider - no one got close unless he crashed.
The cylinder liner has been plated now, and it runs all day just fine - the rider is busy doing other stuff so it hasnt been out for some time.

SpeedPros new setup is for a few customers, not his own use - and I am doing the pipe layout to suit 192* and 12,000,so will be interesting to see how a low
20s 2T goes with good handling and riders.

Blah blah blah, back in the day so and so whet fast and won a race. This is 2012 and for the last 4 years the GPs and BOB have been dominated by guys riding heavy 4 stroke commuter bikes.:bleh:

[bucketracer]

I also wonder if the Suzuki GP100 has a lower primary drive ratio that the GP125? And, if so, are they interchangeable? This could sort out some of those big gaps between upchanges (Oh and alter your power output on the dyno too)

I would be interested in seeing the maths that support your assertion that a change in the primary drive ratio alters the power output on the dyno.

263363

A graph you posted of a multi gear run.

Three different overall gear ratios and pretty much the same power output from each.

Changing the primary gear ratio affects the overall gear ratio just like changing gears does. But as we can see from the graph there is no real change in rear wheel hp.

Maybe you missed it when I first asked you, but I was hoping someone who knows so much could explain their claim in terms that make sense.

[SS90]

Blah blah blah, back in the day so and so whet fast and won a race. This is 2012 and for the last 4 years the GPs and BOB have been dominated by guys riding heavy 4 stroke commuter bikes.:bleh:

Yea, that's so true, is it because they are easy to ride fast compared to a peaky 2 stroke?

I had well and truly expected a two stroke to have been winning again by now, but as Wobbly pointed out, some people just aren't playing just now, and it's just about "the best of the current bunch"

[bucketracer]

This is getting exhausting. At first you mention a lack of primary gear ratios, then you tell me you knew all that. Same with the gear ratios. Now you complain about having only 4 gears. Next thing will be the 10 inch scooter wheels and tires? I don't get it - and I don't have to.

Hi Haufen, welcome to the net where some posters substitute endless talk and bragardo for real substance and become snide if you chalange them, get that every where I expect, like pubs, and clubs where there is always a big noting talker.

TeeZees 30hp engine makes 20+hp at 10500rpm.

TeeZee diarys his work whatever the result, good and bad, if anyone doesn't wan't to build a 30hp Bucket then don't would be his opinion.

Some of the FXR's lining up on the grid make a bit more than 20hp.

And anyone wanting to set the world on fire with a 20-22hp 2-Stroke are more than welcome to post their progress and results here.

[richban]

Yea, that's so true, is it because they are easy to ride fast compared to a peaky 2 stroke?


Put the same people on a 2 stroke and the same result me thinks.

Best of current crop is faster than the old dogs for sure. Young hard charging kids that can peddle a 600 fast as well as a bucket are the ones to watch out for. Us old dogs are getting put out to pasture.

[SS90]

Put the same people on a 2 stroke and the same result me thinks.

Best of current crop is faster than the old dogs for sure. Young hard charging kids that can peddle a 600 fast as well as a bucket are the ones to watch out for. Us old dogs are getting put out to pasture.

How relaible are the 4 strokes that do all the winning, I mean how many hours before a front running engine needs valves? (a fast ZXR400 needed valves and shells every season, and they are not cheap I can assure you.)

A low revving (in context) 2 stroke should be able able to do a season on nothing more than a couple pistons and a few more rings I recon, they do in the European geared scooter racing anyway, it's only the high revving 30 plus horsepower engines that need cranks halfway through...

[Haufen]

Calm down schatzi!

I build small frames for a living.

Have you had the opportunity of tuning a 2 stroke with more than 4 available ratios? No matter how you shuffle the cards, that, and than alone, is what holds you back.

Even at Stokach, where blech roller quarter miles reach frightening speeds, or the once a year 2 laps of the Nurburgring, where the limit is pushed further still, if these engines had more available gear ratios, then we would be able to build engines with more power (just over a narrower RPm range)

Don't worry, I am calm. Although our conversation somehow reminds me of that saying about arguing on the internet and the olympics.

My hope was more that you live for building smallies.

Yes I have had that opportunity, more than 4 as well as cvt engines. But the number of gears is only one side of the coin. The other one, which is the key to making peaky engines drivable, is the ratio between the gears. And my point is, that even on a very peaky engine, you can get your 4 gears close enough to each other to stay within the powerband at any time and still go ridiculously fast on the straights.

Another point in this case is that a gear shift takes time. Time in which the engine otherwise would be accelerating. Looking at the Italian sprint scene (150m), most of the riders use only 3 of their 4 gears. That is not because they would not get their gear ratios close enough to each other to make use of all 4, but because they are faster using 3 and thus saving one shift.

Italian 50RWHp Smallie using only 2 gears for 150m:

http://www.youtube.com/watch?v=QagN7lJhB3w&feature=related

[bucketracer]

I also wonder if the Suzuki GP100 has a lower primary drive ratio that the GP125? And, if so, are they interchangeable? This could sort out some of those big gaps between upchanges (Oh and alter your power output on the dyno too)

I would be interested in seeing the maths that support your assertion that a change in the primary drive ratio alters the power output on the dyno.

263363

A graph you posted of a multi gear run.

Three different overall gear ratios and pretty much the same power output from each.

Changing the primary gear ratio affects the overall gear ratio just like changing gears does. But as we can see from the graph there is no real change in rear wheel hp.

Maybe you missed it when I first asked you, but I was hoping someone who knows so much could explain their claim in terms that make sense.

SS if you know so much why can't you answer a simple straight forward question about one of your claims ????? Your not ducking the question are you ???? I would be dissapointed as I was very interested in the answer because gearing is something we take a keen interest in.

[F5 Dave]

. . . (as the fastest bucket in New Zealand is currently a 4 stroke 150, as races are won on lap times, not back straight speed)....
Whilst that might be true, - it isn't.

While I was making a good stab at keeping the young lads honest on my low-mid 20s MB100 & reckon I could have raced for the lead, given some more laps [blah blah old man wibbling on] after I'd made the drive of shame home young Nat was doing the buss on a low 20s Derbi 80. The fact he fell off doesn't make the 4 stroke fastest. DaveM on Mikes bike had it continued would have done pretty well & very likely won once he'd got used to pedalling said beast.

[SS90]

My hope was more that you live for building smallies.

Yes I have had that opportunity, more than 4 as well as cvt engines. But the number of gears is only one side of the coin. The other one, which is the key to making peaky engines drivable, is the ratio between the gears. And my point is, that even on a very peaky engine, you can get your 4 gears close enough to each other to stay within the powerband at any time and still go ridiculously fast on the straights.

Another point in this case is that a gear shift takes time. Time in which the engine otherwise would be accelerating. Looking at the Italian sprint scene (150m), most of the riders use only 3 of their 4 gears. That is not because they would not get their gear ratios close enough to each other to make use of all 4, but because they are faster using 3 and thus saving one shift.

Italian 50RWHp Smallie using only 2 gears for 150m:


Yea, I have seen Italians and their 150m sprints, totally different kettle of fish really (wheelie bars on a scooter, never thought I would see that.) and scootermatics dealing to CBR600s on a quarter mile??????? Has to be seen to be believed!

But back to the primary ratios, sure this is why I suggested it a few pages back, simply because it will mask the problem that the Suzuki GP 125 has in terms of gearing (that it only has 5 ratios, and the last 2 are too bigger a jump for the power spread to be able to pull), but this assumes that the GP100 has both a shorter primary ratio, and that it would fit a 125, unlike a smallie, you don't have to split the engine to do it either! Lowering the blowdown time area and building an exhaust to suit will also help immensely. (at the cost of a few horses, but....Meh, who cares, just over 20 HP 4 strokes are winning these races anyway)

[Haufen]

Hi Haufen, welcome to the net where some posters substitute endless talk and bragardo for real substance and become snide if you chalange them, get that every where I expect, like pubs, and clubs where there is always a big noting talker.

TeeZees 30hp engine makes 20+hp at 10500rpm.

TeeZee diarys his work whatever the result, good and bad, if anyone doesn't wan't to build a 30hp Bucket then don't would be his opinion.

Some of the FXR's lining up on the grid make a bit more than 20hp.

And anyone wanting to set the world on fire with a 20-22hp 2-Stroke are more than welcome to post their progress and results here.

Thank's for the welcome!:drinknsin

Has it already been considered buying an Aprilia RS125 engine (off ebay for example), taking advantage of the powervalve and the better gearbox? Seems like a pretty good starting point for a bucket engine to me.



gearing is something we take a keen interest in.

Years ago I found an excel sheet on the net that graphically outputs force at the rear wheel. You can compare different gearbox settings as well as find optimum shift rpm for each gear change. If you don't already have such a tool I will dig it up.

[SS90]

Whilst that might be true, - it isn't.

While I was making a good stab at keeping the young lads honest on my low-mid 20s MB100 & reckon I could have raced for the lead, given some more laps [blah blah old man wibbling on] after I'd made the drive of shame home young Nat was doing the buss on a low 20s Derbi 80. The fact he fell off doesn't make the 4 stroke fastest. DaveM on Mikes bike had it continued would have done pretty well & very likely won once he'd got used to pedalling said beast.

Its gutting that Speedpros engine expired, the last year it was never reported to fail (bad luck I guess)
It occurred to me last night that just because 30 HP has been achieved (I am impressed, and Wobbly had been saying that it would happen for ages) it all of a sudden, has become "what you need to win", when, well, it isn't, because going by current affairs, what you need to win is an FXR on slicks.

I truly believe in the future it will be 30hp 2 strokes (reliable ones) though, but I am certain it won't be from engines with single exhaust ports, it's just pushing ring and piston life too far, and to get that power, serious blowdown is required, and therefore narrow power, requiring either a change in gearbox speed (primary ratio possibly) or somehow more, closer ratio gears.

[richban]

I truly believe in the future it will be 30hp 2 strokes (reliable ones) though,


Nah it will be 28hp high reving 4 strokes that go around corners fast.:msn-wink:

[crazy man]

if you had the same bike one with a 2 stroke in it the other with a 4 stroke . same hp . first thing is the 2 stroke would end up 5 kg's lighter , you can stop one qicker into the corner been lighter and a lot less engine com . on a bigger gp type track the 2 stroke power is prombly in a better place but the smaller tracks 4 strokes in general have a better speed of power and reliability but a 22hp stroke should last not to bad

[wobbly]

Reread the recent post where I said that NoMates won 3 straight titles on a 28+ RWHp 2T and was unbeatable.
Because it had plenty of power, plenty of powerband with a PV ( pulls from 6000,spins to 13500 )
a fast chassis, and a mad rider.
Sure, with Av on a RS125 and only low 20 Hp its a winner, but bring out the 28 Hp in the same chassis , and a quick rider,and she would get blitzed as well.

[crazy man]

Terry Fitzgerald had mid 70s (GsxR400) Andy Bolwell, Bredan Gere and John Lowther (all ZXR400's) had something similar, Chis Huddlestone had 68 (ZXR 400) and Adrian Main had 71hp (GSxR400)

But yea, as I am sure you are aware, Steve Ward had the measure of them all (most of the time), as did Glenn Hayward (even on his NX4 framed fiddler special) Jason Easton, Cam Horgan and quite a few others.

That was after Methanol was banned (boo), and before the 450 rule came in, where 80hp was the number for a big bore 400.my bike had 67hp and was every bit as fast as andy bolwell bike and terrys also. they were at lest 25kg lighter than me

[TZ350]

Nah it will be 28hp high reving 4 strokes that go around corners fast.:msn-wink:

Pay attention http://www.kiwibiker.co.nz/forums/images/smilies/eek.gif , because there could be a clue here.

[SS90]

Reread the recent post where I said that NoMates won 3 straight titles on a 28+ RWHp 2T and was unbeatable.
Because it had plenty of power, plenty of powerband with a PV ( pulls from 6000,spins to 13500 )
a fast chassis, and a mad rider.
Sure, with Av on a RS125 and only low 20 Hp its a winner, but bring out the 28 Hp in the same chassis , and a quick rider,and she would get blitzed as well.

Granted, I'm not saying that's not true, but like you say, both scenarios require special riders, as you know, 2 strokes can be made fast,easy to ride and reliable. Much like a 2 stroke enduro bike.

[SS90]

my bike had 67hp and was every bit as fast as andy bolwell bike and terrys also. they were at lest 25kg lighter than me

Ok then. The dyno I used measured higher!:laugh:
But Terry's was always quicker than Andys in a straight line

[TZ350]

Nah it will be 28hp high reving 4 strokes that go around corners fast.:msn-wink:

You realy should stop talking and pay attention to this ...... as there is a clue here.

[crazy man]

Ok then. The dyno I used measured higher!:laugh:
But Terry's was always quicker than Andys in a straight linewhat did a stock 600 suzuki around the year 2000 read on your dyno?

[SS90]

what did a stock 600 suzuki around the year 2000 read on your dyno?

Never had a stock 600, but James Smiths (ex brenden Gere) was (from memory) 110 (this was a few years ago mind, so a bit foggy) one thing I always remember is a standard 1995 Rs 125 made 41, and a b kit made 43up, 1989 NX4 37hp

[richban]

If you say had a 158cc single 4 stroke with a really nice plain bearing bottom end. Custom light forged piston. Redesigned port layout. An ingitech allowing 14000 to 15000 rpm. Flowed head that can pump 32hp worth of air. Massive titanium valve's and huge cams and a close ratio 6 speed in a good frame and a total bike weight of 82kg. That should go ok don't you think.:innocent:

Thats what I want. Might be a bit loud.

[crazy man]

Never had a stock 600, but James Smiths (ex brenden Gere) was (from memory) 110 (this was a few years ago mind, so a bit foggy) one thing I always remember is a standard 1995 Rs 125 made 41, and a b kit made 43up, 1989 NX4 37hpall the 600 suzuki's on my dyno jet were 102-103 . l once dyno'ed a worn out one at 104.5 it was put on ray's dyno later that month and put out 115 hp on his !! . denis charlet tryed his bike on 3 dyno jets around the place and all were no more than a 1hp out to each other

[crazy man]

If you say had a 158cc single 4 stroke with a really nice plain bearing bottom end. Custom light forged piston. Redesigned port layout. An ingitech allowing 14000 to 15000 rpm. Flowed head that can pump 32hp worth of air. Massive titanium valve's and huge cams and a close ratio 6 speed in a good frame and a total bike weight of 82kg. That should go ok don't you think.:innocent:

Thats what I want. Might be a bit loud.that would kick ass for a lap before mr bang lol . if it stays together it should be a goody

[SS90]

all the 600 suzuki's on my dyno jet were 102-103 . l once dyno'ed a worn out one at 104.5 it was put on ray's dyno later that month and put out 115 hp on his !! . denis charlet tryed his bike on 3 dyno jets around the place and all were no more than a 1hp out to each other

Yea, I don't get too carried away with small differences, apples with apples and all that, but I am pretty sure a 6hundy set up for proddy racing 10 years ago was about 110

[Kickaha]

with a really nice plain bearing bottom end.

Why a plain bearing bottom end?

[TZ350]

Why a plain bearing bottom end?

A plain Brg can carry more load and rpm, notice rpm .....

Rich's posts are carrying a big hint about where things are already at and are going to with some of the FXR's that are on the front row of the grid ......

[richban]

Why a plain bearing bottom end?

Sounds cool. I know the KTM 250 dirt engine revs to 13000 all day with a normal bearing setup. Mr honda has gone plain bearing for the moto3 engine. Not sure what the others have done. There is plenty of power in the current engine setup its just up out of reach at the moment. Its all about chasing the weakest link.

[richban]

A plain Brg can carry more load and rpm, notice rpm .....

Not sure at what rpm things get a little stupid on a single OHC 4 banger. 14500 sound like a good number.

[wobbly]

And there is the key to what TeeZee is saying
150cc 4T at 14500 needs over 200psi bmep to go mid 30s crank power.
Full house intake and exhaust tuning, mega cams, tons of TDC overlap, and you think the 2T powerband is too narrow at 30Hp,try riding that FXR.
Sure Kev could make it happen, but I think the reliability cost and rider ability needed is out of reach to most.

[speedpro]

Pay attention http://www.kiwibiker.co.nz/forums/images/smilies/eek.gif , because there could be a clue here.

about how fast the 190cc bikes are??

[speedpro]

Nearly every recent post ignores the rider aspect. I'm not ever going to win a race again and if i recall correctly I have only ever won one in the past. Dave Manuell however is a totally different kettle of fish. Damned shame my bike stopped at Taupo. Rich is on to it though. If one of the fast young guys is put on a good 2-stroke it will immediately be in witha a chance whereas the exact same bike with me on it will be cruising around well away from the pointy end. Nathaniel being a good illustration of the point I'm making.

[richban]

And there is the key to what TeeZee is saying
150cc 4T at 14500 needs over 200psi bmep to go mid 30s crank power.
Full house intake and exhaust tuning, mega cams, tons of TDC overlap, and you think the 2T powerband is too narrow at 30Hp,try riding that FXR.
Sure Kev could make it happen, but I think the reliability cost and rider ability needed is out of reach to most.


Agreed.

Chasing top end power does tend to turn your nice liner 4 stroke into a bit of a 2 stroke. I am sure there is a happy place. It's cost and compromise. And riding for sure. I am 3 hp down on my old engine but still doing the same lap times. Kart track that is. In the GP I couldn't even hold in a slip stream with Dave or Andrew A. Needs them ponies there for sure.

[richban]

Nearly every recent post ignores the rider aspect. I'm not ever going to win a race again and if i recall correctly I have only ever won one in the past. Dave Manuell however is a totally different kettle of fish. Damned shame my bike stopped at Taupo. Rich is on to it though. If one of the fast young guys is put on a good 2-stroke it will immediately be in witha a chance whereas the exact same bike with me on it will be cruising around well away from the pointy end. Nathaniel being a good illustration of the point I'm making.

Yeah after seeing Dave M on Avalons 125 at HD he was my favorite for the GP. Also Avalon is super fast these days. I was thinking a fight between them for the win. Also if Gaz gets a few more HP he is a weapon for sure. Plenty of talent out there. Its great that F4 is attracting these great riders. North island short track series next year will be a cage fight.

[F5 Dave]

. . . In the GP I couldn't even hold in a slip stream with Dave or Andrew A. . .
That's 'cause your profile was considerably bigger than my wake.:laugh:

[crazy man]

Agreed.

Chasing top end power does tend to turn your nice liner 4 stroke into a bit of a 2 stroke. I am sure there is a happy place. It's cost and compromise. And riding for sure. I am 3 hp down on my old engine but still doing the same lap times. Kart track that is. In the GP I couldn't even hold in a slip stream with Dave or Andrew A. Needs them ponies there for sure.l thought you could not hold a slip stream because of that cash they sliped you lol .what kind of power are you getting out of your engine? and who's dyno

[goose8]

Yes I think team shnanny could be one to watch next gp QUOTE=richban;1130320623]Yeah after seeing Dave M on Avalons 125 at HD he was my favorite for the GP. Also Avalon is super fast these days. I was thinking a fight between them for the win. Also if Gaz gets a few more HP he is a weapon for sure. Plenty of talent out there. Its great that F4 is attracting these great riders. North island short track series next year will be a cage fight.[/QUOTE]

[richban]

l thought you could not hold a slip stream because of that cash they sliped you lol .what kind of power are you getting out of your engine? and who's dyno

Old faithful 22 / 23

Dead one 25 / 26

Motormart Dyno dynamics dyno.

Depending on who you talk to a dynamics dyno will read lo. But some people say hi. Personally I don't care. The faster engine also had a lot more lo end grunt and more top end as well. Oh how I miss the power.:facepalm:

[TZ350]

263398

Well now that the numbers are out I can post the dyno graph, 25hp and 6,000rpm range.

Also, now that Rich knows the formula for 25hp, I am betting he will get it reliable too.

There can be no doubt that other FXR's have crossed the 20hp barrier and are following closely in his foot steps.

Still I think the 2-Stroke boys would be pretty safe building low 20's engines. I mean, what could go wrong with that approch?, as they could always try to make up any hp short cummings with superior riding skill.

[TZ350]

I think I will keep working on getting my 30+ hp engine reliable .....:msn-wink:

[bucketracer]

Nah it will be 28hp high reving 4 strokes that go around corners fast.:msn-wink:

263404


Old faithful 22 / 23 Dead one 25 / 26 Motormart Dyno dynamics dyno.
The faster engine also had a lot more lo end grunt and more top end as well. Oh how I miss the power.:facepalm:


i can't claim responsibility for this engine, but (so far) the highest power i have seen from this capacity with a 24mm carb is this series of runs.

263405


What is possible is say 22-25 HP at 10,500, and that, from my experience is not only feasable, but race winning as well.

Probably been talking to much and not listening ........

[Rick 52]

21hp in a RS still gets blown away on big track and only just hangs onto Gavs FXR on the short tracks, 25hp is needed to live with any sorted 4T ! Nathaniel was on The faster of the 2 bikes at Taupo and that has 25hp and it's a shame he could not hold on to it for a few more laps ..

[F5 Dave]

well a shock that hadn't spewed its guts may have changed the outcome for the lad.

Didn't I qual 3rd at Easter Kaitoke? (well, as of Sat night, Rich turned up & bumped a spot sunday). That was a short track on a 2 stroke. I'm not sure I could do that again, but it was helped by me (unintentionally) blocking Kel getting past I'm pretty sure. But I have to rub that in. Beat by a 50, the both of you:third:. I'm working on the principle that practice counts more than the racing.:laugh:

[richban]

263398

Well now that the numbers are out I can post the dyno graph, 25hp and 6,000rpm range.

And now that Rich knows the formula for 25hp, I wouldn't be betting he won't get it reliable.

Also there are no doubt other FXR's that have crossed the 20hp barrier and following in his foot steps.

Still I think the 2-Stroke boys would be pretty safe building low 20's engines, I mean, what could go wrong with that approch.


When that result was recored I was having a major problems with the carb falling apart and not enough time / money to sort it proper. After that me and Andrew went to the track and dialed in the bottom end jetting and the main proper. The promising thing is that there is no drop of in power at all at the top end. When the ingntech gets installed it will be interesting to see what's hiding up at 14. Don't forget the CBR's wish I had one of them sitting in the shed. water cooling would be nice.

[TZ350]

Decent power and a broad spread in a good handling chassis is the aim.

I think a spread of 5,000rpm at near peak power (28-30hp) could be done and I have already posted my ideas on how to make an all conquring 2-Stroke engine with this sort of power spread a few pages back.

[kel]

Didn't I qual 3rd at Easter Kaitoke? (well, as of Sat night, Rich turned up & bumped a spot sunday). That was a short track on a 2 stroke. I'm not sure I could do that again, but it was helped by me (unintentionally) blocking Kel getting past I'm pretty sure. But I have to rub that in. Beat by a 50, the both of you:third:. I'm working on the principle that practice counts more than the racing.:laugh:

No mate you didnt block me, in fact you showed me the fast way around the track.
I dropped back with a couple of laps to go and tried to put in a couple of quicker laps, caught and passed you (in a straight line :bleh:) only to get completely shut out by whoever the next rider was. Crashed during the race while trying to lap the same bike. Crappy end result but a great weekends racing all the same. Can't wait to come back.

[richban]

Decent power and a broad spread in a good handling chassis is the aim.

I think a spread of 5,000rpm at near peak power (28-30hp) could be done and I have already posted my ideas on how to make an all conquring 2-Stroke engine with this sort of power spread a few pages back.

Well we can all hide away in the shed this winter and work on our little projects. Lets all show our hands at BOB. Plenty of hp helps at Ruapuna for sure. Truck down 20 bikes? Lets float that idea closer to the time.

<iframe width="420" height="315" src="http://www.youtube.com/embed/GWS3PkF1ZNc" frameborder="0" allowfullscreen></iframe>

[TZ350]

263421

I have already talked about sleeves with side exhaust ports as a way of improving ring and piston reliability but fitting a sleeve brings its own problems, so we probably won't be going there.

263422

Spurred on by Frits we striped the Beast and lowered it at the front as much as we can and jacked the back up a bit just to see what can be done.

It looks like a CRM450 tank could go in there, shifting the petrol weight forward like Yow Ling suggested.

And a long light weight MX seat and sub frame to get rid of some of the rear ward weight like Richban suggested.

And moving the engine forward a bit like Frits suggested, might be possible too.

The long MX seat could make it easy for shifting ones weight around, the Beast might end up looking like a cross between a Flat Tracker and Road Racer, it should be good.

[TZ350]

Truck down 20 bikes? Lets float that idea closer to the time.


Sounds Good.

[husaberg]

Never had a stock 600, but James Smiths (ex brenden Gere) was (from memory) 110 (this was a few years ago mind, so a bit foggy) one thing I always remember is a standard 1995 Rs 125 made 41, and a b kit made 43up,1989 NX4 37hp

Gee you must have been a gun to get hold of a NX4 in 1989 ?
It was hard enough to get hold of one in 1995 when Honda First started Manufacturing them.



Right for those who don't follow the thread i will outline my bucket build.
It consists of A JC20 NSR125 Engine chosen mainly for it more modern qualities.

It is Water cooled Case Reed has a Exhaust valve and all around Hondalishness.

Others looked at were the RGV100 been done TZR100 been done also the Aprilia 125 and the Cagiva 125 (Mito)these were rejected for various reasons.

The bore and stroke chosen are squarish ie 50mm x50.6mm. So it will be debored and destroked. $ no way around it bugger...
The piston is a oversize CR80.(Bought)
It will have a CR125 Alternator. (Bought)
Ignitech ignition. programmable. (Bought)
Keihin carb with TPS and an electric Powerjet. (Found must get around to paying for it)
Wobbly Parana (or is that Barracuda) exhaust.
Wobbly speced engine.

Chassis consists of a Prehacked about Rs125 NF4 Frame shocks and shocks. (Bought)
Wheels 2.5x17 CBR250 front with Cast iron floating RS125 diSK Brembo 4 pot caliper and RS MC.(Bought)
Rear 3.5x17 CBR400 front wheel with RS like cush drive for the Sprocket scooter disk and KTM 50SX caliper and MC. (Bought)

As it is designed for open tracks the Target HP is somewhere north of 24hp.

Muzza B is kindly bringing over the chassis this week from CHCH so a special thanks to Muzza B and for Crazyman and Bert for organizing its escape from the north Island.
Wayne (Wobbly) and Lozza (2tinsitute) for organising the Engine from Japan via Australia.

It isn't a how to build 10HP bucket for $100 but it is a still Budget build.

let the construction begin.

[Gigglebutton]

Would it help if we cut a sectoin of frame rail away, where the Deltabox sticker is. Then weld the shock and swingarm mount back ??

263422

[bucketracer]

I truly believe in the future it will be 30hp 2 strokes, but I am certain it won't be from engines with single exhaust ports, to get that power, serious blowdown is required, and therefore narrow power, requiring either a change in gearbox speed (primary ratio possibly) or somehow more, closer ratio gears.

You should look at TeeZees 30hp graph more carefully before talking any more about narrow power bands and the need to change the primary gear ratio or suggesting a closer ratio gear box because your way off the mark there.

263438

TeeZees 30ps (DIN hp) at 12500 rpm with a useful 4k torque curve from 11 to 17.5Nm. (13 ft/lbs = 17.5Nm)

How wide do you think yours is? from your 20ps 8Nm graphs (attached below) and taken from engines similar to TeeZee's it looks like its 2.5k, 3k at best.

So that begs the question, how wide a torque curve does a 4 speed Vespa need?

If you know the rpm drop between gears lets see if TeeZees 30hp 4k curve would work ok on a Vespa too.

My guess is ... Yes ... and probably better than your race winning combos shown below.


What is possible is say 22-25 HP at 10,500, and that, from my experience is not only feasable, but race winning as well......

TeeZees Graph is 22+hp at 10,500rpm so your right, it is feasable.

The idea of lower rpm and a broad strong spread is not that silly and TeeZee posted his ideas 20 or so pages back on how it could be done and a pipe design to go with it.

[TZ350]

I think you can be very happy with your regulations, as it looks like they allow for a great amount of freedom of choice without any setups / directions being superior to the rest. Too bad I am living on the other side of the planet, if I were in NZ, I'd surely take part. Are there any european 125cc two-stroke street bikes available in NZ, for example Aprilia RS125, or Cagiva Mito (Evo)?

And, by the way, this thread is a great read! I really like the attitude of sharing experience and helping each other which is present here :rockon:

Very few small European bikes available in NZ and they are relativly expensive. The bikes here are mostly the std Honda/Suzuki/Kawasaki's.

I am glad you enjoy the thread, I started it a while ago just to wind up the opposition before the annual Taupo Road Racing Spectacular, TRRS for short.

While I plod along diarying my own and something of Team ESE's success and failures with development other contributors have added their bit and it has morphed into something that’s both entertaining and useful.

And we are very lucky to have real technical and industry experience with Wobbly and Frits, their input adds real depth and understanding that’s invaluable and I am very grateful for what I have learned from them.

Even if someone does not want a 30hp engine like mine there is plenty of info posted by the community here, to help them make whatever they like.

If you would like to post about your projects it would be welcome as we are always interested in someone else’s work.

[TZ350]

Would it help if we cut a sectoin of frame rail away, where the Deltabox sticker is. Then weld the shock and swingarm mount back ??

263422

I had gone off the idea of cutting the frame because the stearing head to seat length was already the same as a Honda RS125.

But now that I am changing the tank and set, frame cutting might be worth looking at again.

Kel is coming around Friday night, if you can, please pop in too and we can all look at whats possible.

[F5 Dave]

I'll bring the beers & the hacksaw.


oh hold on, you're 600 odd k away.

[TZ350]

I'll bring the beers & the hacksaw.

If you can get here we will shout the beers and lend you a hack saw..... :msn-wink:

[F5 Dave]

Hmm, $91 grabaseat & I do drink a bit so it could be worthwhile to come get trashed & saw your bike to bits. Hmm, carry-on bag, would fit my 125 grinder & I'm dangerous with that.:laugh:

[speedpro]

I can get an 8" grinder with cutoff discs. We'll have that thing in small pieces in no time

[TZ350]

Hmm, $91 grabaseat & I do drink a bit so it could be worthwhile to come get trashed & saw your bike to bits. Hmm, carry-on bag, would fit my 125 grinder & I'm dangerous with that.:laugh:


I can get an 8" grinder with cutoff discs. We'll have that thing in small pieces in no time

Well OK beers for all, hopefully after an hour or two every one will have forgotten what they came for... :drinknsin:D:drinkup:

[F5 Dave]

or after a few hours when you come to weld it all back up again the wheelbase will be so short the back of the front tyre will rub on the front of the rear:eek:

[TZ350]

I see the four essential things for a winning formula as, Rider, Handling, Power and the way the power is Delivered.

If the opposition is a rider you can't out ride, and he has a good handling bike the equal of yours and you both have sufficient power then that only leaves "Power Delivery" as a possible advantage.

263469

And usually 4-Strokers are better at that than 2-Strokes, and the reason 4's are so hard to beat.

So what to do????


SS90, TeeZees 30hp Graph is 22+hp at 10,500rpm so your right, it is feasible.

Your idea of lower rpm and a broad strong spread is not that silly and TeeZee has already posted his ideas, 20 or so pages back on how it could be done and a pipe design to go with it.

22-25hp at 10,500rpm is easily feasible but now that FXR150's are starting to creep into the low 20's and with some turning 25+ on the dyno a 22-25hp 2-Stroke might not be all that much of an asset.

But your right "lower rpm and a broad strong spread is not that silly" its just you may need to aim for 25-30hp to have a competitive stroker.

This is the original post.


After we get the triple port and Piranha pipe testing out of the way I want to try my hand at one of these Trombone pipes. They look like the key to making an all conquering 2-Stroke.

The plan is to make a pipe that works well down low and then use the Trombone effect to get lots of extension of the working range. Not so much about peak hp numbers, that 2-Strokes can be good at but dramatically increasing the area under the power curve.

After Frits revelled the Trombone concept I immediately could see that it had real possibilities if we could get it to work for us.

Using a traditional expansion chamber has its limitations because its limited to a relatively small range where its in resonance, 3-4K at best an the 4-strokes can pull 6k.

The Trombone Frits showed us I think was made to extend the range above and below a full race pipes natural resonance point.

263468 Trombone simulated in EngMod2T and graphed in kW's

After doing some investigation it looked like the Trombone was better at extending a pipes range than lowering it.

So to get a better, broader power delivery my idea was to design a pipe more like a torquey MX one that works very well at relatively low rpm and use the optimal exhaust port duration for resonance that Frits has talked about.

Then use the Trombone principle to progressively shorten the header until the engine reaches its mechanical limits at 14,000rpm or so.

If extra power is only worth tenths of a second and handling whole seconds, but the other bike is as good as yours and the other rider is a mad psycho. What are you going to do, out ride him? I don't think so, then that only leaves Power Delivery as a possible advantage.

The trombone might be the answer.

[Farmaken]

What was that saying?- Measure once, cut twice:Oops:

Good luck TZ

[TZ350]

Frits has motivated us into looking at the Beasts handling.

263473

My CRM Tank and Seat arrived today and yes, it looks like I can use it to get the fuel and riders weight forward.

Make a light sub frame for the back and with a MX tail and number boards it should look quite the bizz, or at least pretty unusual, even for a Bucket.

263475

Comparing the CRM tank and seat to an original FZR one, it looks like the rider will be able to move around and get their weight up front when needed OK.

When you look at the original (No 21) FZR, it looks so restrictive.

263474

Yep, fits a RG50 too.

263476

Getting the engine forward in a small race chassis makes it tricky building a good pipe. I am glad I have a roomy FZR chassis.

263472

Stuff every where, house keeping is obviously not big around here.

263477

And Bucket, the "Industrious Man" or is that Industry Man? is busy working on cylinders.

[F5 Dave]

Tell you something for nothing. the engine in the NX4 is too high.

[speedpro]

263477

And Bucket, the Industrious Man is busy working on cylinders.

So that'll be a 500 V4 when finished?

[TZ350]

So that'll be a 500 V4 when finished?

Yes and low 20's race winning hp ..... we are reaching for the stars don't you know.

[Yow Ling]

263477

And Bucket, the "Industrious Man" is busy working on cylinders.

SO the question is are these ported to the NTSC standard?
(never twice the same cylinder)

or are you guys flasher than that?

[husaberg]

And Bucket, the "Industrious Man" is busy working on cylinders.:laugh:

Assuming you were to cut the chassis (I would build a Spine frame myself)
I would remove the whole curved section. Then replace it with a straight section as you have ample room around the sides of the cylinder even if the means lowering the engine to clear.

Yeah then i would also tilt the engine forward so then 2 birds one stone.

Well actually four birds as the pipe run will be less in the way of the Tyre as well as well as the weight further forward.

What ever you do make sure, you simulate the full movement of suspension for the front. (i know you will Rob)

If the chassis was cleaved at the std weld line in the spars, you could install a whole front spar and steering head section.
That way if need be you would be able to put it back to Std if you ever wanted to.

BTW I did some real quick calculations and i also think you will need to drop your fork offset by 20-25mm to achieve the numbers Frits was mentioning. with regards to Rake and Trail. (20 degs and 85-95mm trail) Which would mean trailbike like yokes.

http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=200671&d=1268768942http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=200672&d=1268768942http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=254141&d=1325382220

[wobbly]

Before you get all out of control, consider a couple of factoids.
Turning the cylinder around has alot of advantages in pipe shape as well as allowing easy forward movement of the whole engine - remember the RSW is better than the RSA for that reason alone..
Secondly, I have shown conclusively several times to disbelieving audiences that using a PV can double the power of a highly tuned 2T at the bottom of the useable range.
So - imagine the single exhaust GP125 with double the power at say 6000, then draw a straight line up to its 31 Hp peak at 12500.
A ATAC system can achieve a similar result,the trombone is capable as well,this system has been used in hydro racing forever ( remember Konig and the Kiwi ).
So getting a 4T killer setup is staring everyone in the face, you - meaning Rob et al, just need to commit to one approach and develop it.

[TZ350]

Turning the cylinder around has a lot of advantages in pipe shape as well as allowing easy forward movement of the whole engine - remember the RSW is better than the RSA for that reason alone.

Turning the cylinder around wont happen here but if I succumb and build the H2o version using a TF bottom end then yes definitely it will be a rear facing exhaust.


Secondly, I have shown conclusively several times to disbelieving audiences that using a PV can double the power of a highly tuned 2T at the bottom of the useable range.

As much as I would like one, the air cooled cylinder doesn’t lend itself easily to modification for a PV.


An ATAC system can achieve a similar result, the trombone is capable as well, this system has been used in hydro racing forever.

An ATAC system is on the cards especially if it can be used with a Trombone system.


So getting a 4T killer setup is staring everyone in the face, you - meaning Rob et al, just need to commit to one approach and develop it.

Too true, and is the reason I have stuck with the 125 air cooled and kept focused on engine development at the expense of other aspects of building a fast bike, like handling, but that needs attention now that we are making reasonable power.

Initially, changes will probable only amount to dropping the front, jacking the back and fitting a dicky looking tank and seat and maybe moving the engine forward 50mm.

Unfortunately progress in the workshop does not move along as fast as talk on the Internet. And anything that turns out to be good needs to be easily replicated for the other Team bikes.

So I will lay out the highlights of my engine development plan as a touch stone for when the talk wanders all over the shop and people think we are loosing our way.

And if anyone is interested enough they can tick the list off as we go along.

01) Adjust the timing on the triple port and compression ratio.
02) Re test with the RS pipe (a known quantity)
03) Repair and Retest with the Piranha pipe.
04) Repeat 1 to 3 until the power curve is what we want.
05) Develop a workable ignition curve.
06) Add anti knock to the ignition curve.
07) Test with a 30mm carb and if that makes significantly more power than the 24 then:-
08) Test with a Plenum. The plenum was an idea for getting around the restriction of a 24mm carb.
09) If the plenum shows real promise, develop it.
10) Try Water injection into the pipe.
11) Try Water injection through the carb.
12) Try our hand at a Trombone pipe.

More or less in that order.

And while I am doing this, get some track time, develop the handling, build a F5 bike and make several engines for other team members while earning a living.

[husaberg]

there is a good TV program on, I will come back to this....
http://emol.org/film/archives/mrbeansholiday/98419353,34D71C1DFA537C7B4A0.jpg
is it Bean?

[Yow Ling]

Got a bit done on my GP100 bottom end tonight , cut off the old inlet stub and made a new one , its about 28 id, maybe ill take another mm out or offset the bore as im right up against the O ring on the valve cover.
Looking down the hole looks like there is a bit of coranary blockage to move out of the way

263486

263485


A different thing Ive been thinking of is det counter. I bought one of the knockmeter that Wob put us onto and its pretty cool. I got it with the switching to ground output so I can retard the Ignitech automatically, but I thought it would be good if it could also count the number of times it retards the ignition, I had a OmronH7EC counter in the drawer, if i connect its input on the retard signal it can count the dets just like a $1500 det counter, total investment for knockmeter counter and new knock sensor about $200

263487 263488

[TZ350]

Mr Yow Ling that looks pretty cool .... and I like the knock counter very much, clever idea.

263491

We also found the best we could get with the std cover on the left was about 28mm.

Then machining the "O" ring part of the stub away and sleeving it we could get out to 30mm OK. For sealing without the "O" ring we made the sleeve a good fit in the clutch cover and a little longer than the original so it poked hard into the back of the carb rubber and a little Yama Bond smeared around the stub and clutch cover helped too.

On a couple of clutch covers we machined the hole bigger and cut a small champher for a 3mm "O" ring to go in and around the inlet stub so that the carb rubber squeezed it all up tight, I managed to get 34mm ID that way.

263496

In opening the port window up we broke through and now glue the cases up before even starting to port them.

263494

Std is 105mm the bigger ones are 113 and 117 diameter, I think the Aprilia RS was 127. We aim for 1-1.5mm clearance at the edge and 0.3-0.5mm clearance on the face with a 2mm sealing surface left above the inlet port itself.

With 34mm you need to increase the size of the rotary valve disk. Other wise you will have an inlet area larger than you can easily make the port window.

Anyone who wants to try a larger Suzuki GP100/125 RV can PM me for the Auto Cad file you will need for the Lazer cutter.

263493

The cover on the right has had the "O" ring grove glued up and machined out for a bigger RV. And without an "O" ring, its a dodgy sealing job around the edge with Yama Bond.

263495

The catch is the inner plates diameter is too small for a bigger RV.

263492

So you need to fit a larger inner plate. And to get a really decent sized RV you need to make a new outer cover so it seals properly.

[jasonu]

What was that saying?- :Oops:

Good luck TZ

We do it nice 'cause we do it twice...

[jasonu]

Then machining the "O" ring part of the stub away and sleeving it we could get out to 30mm OK. For sealing without the "O" ring we made the sleeve a good fit in the clutch cover and a little longer than the original so it poked hard into the back of the carb rubber and a little Yama Bond smeared around the stub and clutch cover helped too.

.

That is EXACTLY how I did my KE disk cover and it has never let me down.

[Farmaken]

A question for the panel :

Apart from being as close as pos. to the barrel, should an atac valve be positioned on the outside of the header bend or on the side/inside of the bend ?

gut feeling says outside might cause too much interference with gas flow - whadaya reckon ??

[TZ350]

A question for the panel :

Apart from being as close as pos. to the barrel, should an atac valve be positioned on the outside of the header bend or on the side/inside of the bend ?

gut feeling says outside might cause too much interference with gas flow - whadaya reckon ??

The only one I have seen in real life and all the pictures I have seen, have them on the outside, but it may be, just more convenient to fit them that way.

[wobbly]

If there is any way of getting the orifice on the inside of the bend I would say there would be some gain, as the bulk flow on the inside radius
would be less affected by the disruption.

[Farmaken]

Cheers Wobbly, that could prove a bit of a challenge but now I have a project for the weekend, eh !!!

[Farmaken]

Cheers Wobbly, that could prove a bit of a challenge but now I have a project for the weekend, eh !!!

Any suggestions on a suitable solenoid ?

[TZ350]

263532

Ok ... with the front dropped and the back jacked up a bit we have 18 deg Rake.

Interestingly this did not change the weight distribution much, with a rider aboard in a racing crouch or leaning like they were entering a corner the weight distribution was still 48% front 52% rear, more or less.

263533

By the best eyeball method.

263531

I make the Trail 75mm.

263534.

After a bit of a committee meeting we figured that to move the engine forward the frame could be cut in either of two places, taking 40mm out of the lower section or 80mm out of the top, or may be both, for a total of 120 which is what I was looking for.

Everyone remembered to bring beers but some one forgot the chainsaw so frame surgery will have to wait, maybe get onto it next week.

[Gigglebutton]

After a bit of a committee meeting we figured that to move the engine forward the frame could be cut in either of two places, taking 40mm out of the lower section or 80mm out of the top, or may be both, for a total of 120 which is what I was looking for.

Everyone remembered to bring beers but some one forgot the chainsaw so frame surgery will have to wait, maybe get onto it next week.[/QUOTE]

The beers where good.
The naked dancing in the car park was taking things a bit to far.
Let me cut it Doctor mwah ha ha ha ha ha ha :devil2:

[richban]

After a bit of a committee meeting we figured that to move the engine forward the frame could be cut in either of two places, taking 40mm out of the lower section or 80mm out of the top, or may be both, for a total of 120 which is what I was looking for.

Everyone remembered to bring beers but some one forgot the chainsaw so frame surgery will have to wait, maybe get onto it next week.

Now you are keen on the bike setup and making a real custom weapon. I think the first thing you need to do is chuck the heavy wheels and convert to a 415 chain and sprockets. Better acceleration, Faster direction changes, Less unsprung weight. And most importantly they look the shiz. When I did mine the bike lost 7kg most out of the rear. From memory the front and rear RS wheels I have are the same weight when fitted with disks and rubber. Front rotor I have is rather heavy it has a steel centre not Ali like the expensive ones. If you are going to get serous I would always start from the ground up. Wheels. If you don't want to go 415 you can get rear 428 ali sprockets to fit RS wheels these days and really nice light chains.

Would be interesting to do your distribution test without wheels. Few axel stands wired to the forks and rear swing arm should be safe enough for Kel to balance on. Just make sure they weigh the same.

[husaberg]

263532

Ok ... with the front dropped and the back jacked up a bit we have 18 deg Rake.

Interestingly this did not change the weight distribution much, with a rider aboard in a racing crouch or leaning like they were entering a corner the weight distribution was still 48% front 52% rear, more or less.

263533

By the best eyeball method.

263531

I make the Trail 75mm.

263534.

After a bit of a committee meeting we figured that to move the engine forward the frame could be cut in either of two places, taking 40mm out of the lower section or 80mm out of the top, or may be both, for a total of 120 which is what I was looking for.





A bridge to far perhaps 18 deg and 75mm Frits was at 20 and 85mm ish wasn't it?
Sure it will turn sharp at those figures.so sharp it will probably make you bleed. LOL
But why not start out a little more conservative. 20-22 deg and 85-95mm.

The trail is also a result of the fork offset remember.
That why i mentioned the trailbike yoke to get the offset around to ballpark with the increase rake.

Have a look at the simple rake trail calculators on the Foale site.http://www.tonyfoale.com/ under freeware

[TZ350]

Yes perhaps a bridge too far.

I need to get the Beast running again and finish the engine development with Wobs pipe.

But I am convinced by Frits's argument that hp can only take you so far and that at some point there are more gains to be made with improved handling.

And by taking the seat and tank off, lowering the front and jacking the rear. We now know what we have, what we can get easily and the likely effort required to do it well when we are ready too.

Rich talks about lighter wheels, Chambers made a sister bike (No 21) to the Beast and that has 10-12kg (in total) lighter Junior Motard wire wheels and is parked out in the shed. A lot of the weight saving will be in the rear wheel. Maybe it was this one that was 50/50 with rider, I will dig it out and weigh it again.

[wobbly]

18*/75 is for sure to steep and short, and remember that jacking the back will affect the squat geometry - but I hope you will fix that when you move the engine about.

[wobbly]

18* with 75 is for sure too steep and short.
Jacking the back will affect the squat geometry, but thats fixable when you move the engine.

[TZ350]

More on Rotary Valves.

263547 Traditional Wedge Inlet, a Square gives more Area and requires a different shaped disk.

EngMod2T allows a top and bottom dimension for the port window but seems to prefer that you take a mean average width and use that, in this case its 32mm.

263548 New and Old RV

Its possible to go quite a bit bigger with the RV on the Suzuki GP engine.

263545 105 263546 113 263544 117

The std 105mm RV gives an easy 30mm equivalent diameter port window

The 113mm RV gives 33 and the 117 gives 34 only 1mm more.

263549

The 113 diameter RV for a 33mm effective Dia inlet port is easily done just by gluing up the "o" ring grove in the cover and fitting a new inner plate. Its not to hard to do and the most practical. The 117 means making a new outer cover and is hard work for another mm.

Given the other limitations within the engine, EngMod2T simulations that I have done point to 30mm as being OK and 32 as the most effective and any bigger as a bit of a waste of effort on my engine.

Although this post is about matching the inlet port window to the inlet tract and the amount of work required to gain 1mm, I think one needs to also look at the STA's to get the full picture of what 1 more mm will potently give you, and if its worth the effort power wise.

[SwePatrick]

I´m having a wonder again.

Can´t remember if it already have been discussed, but i´ll write it down for you to see.

I´m thinking of the rejecting gasses in the carb at high rpm´s
Physics says to me that you are 'cutting' off the flow premature.
A reedengine shouldn´t do this if it´s correctrly setup, but reedengines have other restrictions in flow.

So lets solve why it´s rejecting on your disc engine.
Clearly you are wasting kinetic energy from the gasflow, that could have filled the crankhousing(cylinder) instead.
But cutting the disc for later closing might harm the broad powerband you want.
and worth a test is 'smooth closing'.

Then lets concentrate on the exhaust, a really effective pipe sucks gasses through the whole setup when into the tuned register of the pipe.
Is there a way of letting the pipe 'hit the wall' harder and letting it suck earlier in the rpm range?
A pipe tuned slightly lower in rpm with harder pulsetuning, can be hard to reach thou.
But isolating the header to keep the heat in the belly on the pipe helps.
I´f you are loosing heat in pipe you are loosing pressure, and the tuning is lost.
Here in Sweden people have starting to wake up and trying more steep degrees on header and diffusers.
this allows us to use bigger and bigger carbs as the flow is really hard in tuned register.(you are sadly restricted, and building hard flow that 24mm carb cant give, easliy said)
A friend of mine runs 32mm carb on a 65cc setup, this one pulls out about 25hp at the wheel.(actually it could be even more)

My testing would be:
Smooth closing on the inlet, or even later closing.
A pipe with slightly lower rpm tune with harder degrees to get the desired volume, and then isolate it with 'headerwrap' to keep up the heat in the pipe.
And finally put an pressureguage at the very middle of the belly to tune the pressure in pipe with different stingers.

This is a picture of my pipe by the way:
Doesn´t show much thou, but i think i posted a picture earlier in the progress.
https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash3/524424_10150822789124475_540649474_9949610_1464101 733_n.jpg
This shows my homemade silencer with exchangable inserttubes with different diameters to adjust the pipepressure.

aim at 120-130Kpa, you can go higher, but watch the exhausttemp carefully, you might melt pistons :(

[Frits Overmars]

A bridge to far perhaps 18 deg and 75mm Frits was at 20 and 85mm ish wasn't it? Sure it will turn sharp at those figures.so sharp it will probably make you bleed. But why not start out a little more conservative. 20-22 deg and 85-95mm.
The trail is also a result of the fork offset remember. That why i mentioned the trailbike yoke to get the offset around to ballpark with the increase rake. Have a look at the simple rake trail calculators on the Foale site.http://www.tonyfoale.com/ under freewareYou can get away with the 18°. If you take a look at Tony Foale's projects, you may find that he even experimented with zero degrees and got away with it.
But the 75 mm trail will give too little feedback, even if the front is heavily loaded. Like Husa says, yokes with smaller offset can help you out; you should strive for a trail of at least 85 mm.
Light wheels will make a difference like you won't believe. It goes so far that in MotoGP brake disks are substituted with smaller ones on tracks where you do not need the brakes so much.

[Frits Overmars]

I´m thinking of the rejecting gasses in the carb at high rpm's. Physics says to me that you are 'cutting' off the flow premature. A reedengine shouldn´t do this if it´s correctly set upAny engine, whether it's disk, reed or piston controlled, will blow back to some extent. Maybe not so that you'll notice, but it will happen. That's physics too.
When the inlet opens, the pressure difference between the outside air and the crankcase pressure causes mixture to start moving into the crankcase. This inlet flow will accelerate as long as the crankcase pressure is lower than the atmospheric pressure. So when both pressures are equal, the flow will just have reached its maximum velocity. It does not want to stop suddenly, so it keeps on flowing, thereby raising crankcase pressure to above atmospheric pressure. This negative pressure difference slows the flow down until it finally stops.
Ideally you close the inlet at exactly that point in time. But even if you do, the pressure on the crankcase side of the inlet tract will be higher than the pressure on the outside world side. This pressure difference between both sides of the inlet tract will accelerate its contents back to the outside world.
Summary: there will always be some blowback; whether you close the inlet too late, at the optimum timing, or too soon. In the first two cases it may be so slight that it's movement is caught by the next induction event before it can be noticed. In the latter case, the blowback will be really violent.

[husaberg]

You can get away with the 18°. If you take a look at Tony Foale's projects, you may find that he even experimented with zero degrees and got away with it.
But the 75 mm trail will give too little feedback, even if the front is heavily loaded. Like Husa says, yokes with smaller offset can help you out; you should strive for a trail of at least 85 mm.
Light wheels will make a difference like you won't believe. It goes so far that in MotoGP brake disks are substituted with smaller ones on tracks where you do not need the brakes so much.

Yes long ago i had the Foale book (Long lost) he had a BMW with a weird adjustable set up for rake and trail from memory he went sub 20.
but i think the forks which were std style forks became real harsh and didn't cope that well.
I also hazard a guess that the GP bike fork's are also slightly more sophisticated than TZ's Yamaha FZR250 forks as well.:drool:
How much total weight difference are the wheels on chambers bike. I think you said 10kg but was that the bike surely not the wheels?:scratch:
I brought a cheap set of KX85 wheels with the intention of building a super light weight set of wheels with rims with mini supermoto rims but got scared with the price of the rims plus i don't like tubes.

From memory size for size Suzuki i think used to have the lightest wheels with Kawasaki the heaviest and Honda, Yamaha somewhere in between.
https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash3/524424_10150822789124475_540649474_9949610_1464101 733_n.jpg
Oh swedepatrick nice end cap on the silencer mmm... billet

[richban]

Light wheels will make a difference like you won't believe. It goes so far that in MotoGP brake disks are substituted with smaller ones on tracks where you do not need the brakes so much.

I do remember the first proper race after I changed to light wheels. Everything seamed really easy. The bike felt super responsive and changed direction faster. After that I was kicking myself for not doing it sooner. I am a little obsessed with light wheels.

[husaberg]

I do remember the first proper race after I changed to light wheels. Everything seamed really easy. The bike felt super responsive and changed direction faster. After that I was kicking myself for not doing it sooner. I am a little obsessed with light wheels.

Not so much light motors though:laugh: I reckon you could ditch about 10kg if you got rid of all the extra stuff on the top end Rich

[F5 Dave]

What about a light arse? Maybe a salad for lunch instead of a pork pie?

[richban]

Not so much light motors though:laugh: I reckon you could ditch about 10kg if you got rid of all the extra stuff on the top end Rich

Yes well ......

[husaberg]

Yes well ......
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=263584&stc=1&thumb=1&d=1312944342

You may need to take some more out of the sleeve ya think:laugh:

[TZ350]

Page 510 .....

On page 500 Bucket posted links to the basic info needed for building high 20's GP125 Bucket Engine and also this handy list.


Page 500 .....

No need to have a peaky engine. Here are Two Very useful Tools. EngMod2T a 2-Stroke simulation package and a handy (and cheep) Porting Calculator from:- http://www.porting-programs.com/ which is based on Blairs work.

263589Rich's 4-Stroke





There are over 3,500 images on this thread. To find the interesting ones use Thread Tools near the top of this page and View Images, then sort them from the Beginning and 70 to a page. Click on the Image to view it and the little N/A sign to go to the Post about it.

On each decade page, 490, 480, 470, 460 etc there is a collection of links or a collection of the more interesting technical posts from the last ten pages.

A bit of an index .....

Page 490 The Trombone, Ex port resonance and Transfer port stagger.
Page 480 A vid of the Trombone, transfer timing and hot gases entering the transfers because of insufficient blow-down for the rpm.
Page 470 Blow-down STA ... Specific Time Area.
Page 460 No list but the page talks about Boost Bottles.
Page 450 Links to the basic info for building a 30+ hp Bucket.
Page 440 No list, page talks about power and air correction jets.
Page 430 Carb inlet lengths and crankcase volumes.
Page 420 Transfer ports and the importance of the up swept angles, the Leaning Tower of Pisa principle explained.
Page 410 Rolling road dynos, main and power jet ratio.
Page 400 Links to the basic info for building a 30hp Suzuki GP125 Bucket engine.
Page 390 Links to Frits collection of Aprilia stuff.
Page 380 Transfer duct shape and STA's.
Page 370 No list but the page talks about Jan Thiel and racing 50's.
Page 360 Frits chamber calculations formula.
Page 350 PJ switching, Wob and crank shaft balance.
Page 340 Muriatic Acid, main brg float, Husburgs con rod dimensions.
Page 330 No list, page talks about expansion chambers, race gas.
Page 320 High temp silicon, Yama Bond, crankcase sealing, air solenoids Vid clips of Mamola.
Page 310 Copper for cooling, sprockets for cooling, steering head brgs.
Page 300 How to determine STA numbers.
Page 290 B/E dimensions, delivery ratio, Honda Ex Step, stinger nozzel
Page 280 Aprilia RSA port layout explained, pumper carb, links to gluing up the GP cases.
Page 270 Link list on how to make a decent high 20's hp Suzuki GP125 Bucket engine.
Page 260 Over rev cough and what it means, Mallory metal for crank balancing.
Page 250 27hp from a 1978 Suzuki GP125
Page 240 Aprilia RSA cylinder stuff.
Page 230 Porting Calculator and a lot of other useful tech links.
Page 220 RG50 part numbers, 2-stroke carb atomisers explained
Page 210 Page is mostly about the results from the TRRS
Page 200 Simple 18 hp Suzuki GP Bucket engine using a RG250 pipe.

Etc ...

[TZ350]

How much total weight difference are the wheels on chambers bike. I think you said 10kg but was that the bike surely not the wheels?:scratch:

From memory it was 10-12kg difference between the complete wheel assemblys disks, cush drive, sprockets etc, true apples with apples comparison.

When I check Chambers FZR for its weight distribution I will also try to find the spare wheels and check them too.

[jasonu]

From memory it was 10-12kg difference between the complete wheel assemblys disks, cush drive, sprockets etc, true apples with apples comparison.

When I check Chambers FZR for its weight distribution I will also try to find the spare wheels and check them too.

Plus getting rid of unsprung weight vs sprung weight has a much greater benefit.

[wobbly]

Aw cimon youse guys ,do the Britten thing and spin up some carbon string wheels - easy.

[Yow Ling]

A different thing Ive been thinking of is det counter. I bought one of the knockmeter that Wob put us onto and its pretty cool. I got it with the switching to ground output so I can retard the Ignitech automatically, but I thought it would be good if it could also count the number of times it retards the ignition, I had a OmronH7EC counter in the drawer, if i connect its input on the retard signal it can count the dets just like a $1500 det counter, total investment for knockmeter counter and new knock sensor about $200

263487 263488

Tested this goes great !

[bucketracer]

Just watched MotoGP and Stoners win, He was having front wheel chatter problems, so even the big boys struggle with it some times.

[jasonu]

Just watched MotoGP and Stoners win, He was having front wheel chatter problems, so even the big boys struggle with it some times.

Thanks for the spoiler...
On race weekends I keep away from the 2012 Moto GP thread for this very reason.

[bucketracer]

I also wonder if the Suzuki GP100 has a lower primary drive ratio that the GP125? And, if so, are they interchangeable? This could sort out some of those big gaps between upchanges (Oh and alter your power output on the dyno too)

I would be interested in seeing the maths that support your assertion that a change in the primary drive ratio alters the power output on the dyno.

263609

A graph you posted of a multi gear run.

Three different overall gear ratios and pretty much the same power output from each.

Changing the primary gear ratio affects the overall gear ratio just like changing gears does. But as we can see from the graph there is no real change in rear wheel hp.

Maybe you missed it when I first asked you, but I was hoping someone who knows so much could explain their claim in terms that make sense.

"(Oh and alter your power output on the dyno too)" I don't see that it in your multi gear graph or on the dyno at work.

When I asked before, I saw some whiffle from you but not a real answer.

I am very interested in how an experienced engine tuner and dyno man gets different gear ratios to show up as power increases, maybe its an industry secret.

Or just something you said to impress.

[Yow Ling]

Thanks for the spoiler...
On race weekends I keep away from the 2012 Moto GP thread for this very reason.

How many weeks do you think we should wait before talking about it?

[jasonu]

How many weeks do you think we should wait before talking about it?

Yeah fair cop. I thought he was talking about a more recient race. (that is happening next weekend...:Oops:)
Apologies to all concerned.

[husaberg]

Aw cimon youse guys ,do the Britten thing and spin up some carbon string wheels - easy.

Cats cradle? I think they should do some solid wheels from billet.
Do some of the cars have 17's?

[Frits Overmars]

...I think they should do some solid wheels from billet.Should that be depleted uranium or will you settle for tungsten, Husa? :apumpin:
Wob is right: carbon wheels are the way to go. But as John Britten found out while handling the stuff, there is not all that much difference between carbon fibre and asbestos....

[Moooools]

Should that be depleted uranium or will you settle for tungsten, Husa? :apumpin:
Wob is right: carbon wheels are the way to go. But as John Britten found out while handling the stuff, there is not all that much difference between carbon fibre and asbestos....

Yes they don't call it the black death for nothing.
The UoA Formula SAE team I am part of had a crack at carbon wheels (for a car). They found it very difficult to get a good shape for beading the tires. They looked cool though and were nice and light. A bit of Al honeycomb would probably be required and a 4 part mold too. Hard to get right.

[speedpro]

Rich is expendable. We should get him onto producing carbon wheels for us bucket racers.

[husaberg]

Rich is expendable. We should get him onto producing carbon wheels for us bucket racers.

Before we get all excited about sacrificing Mr Ban.:laugh:

Frits what is the life span of the CF rims, and how well do they perform when someone hits a pot hole or ripple strip?

the billet wheel car comment was in regards to them having blanks of a suitable size to modify.

If you follow this post click on arrow after Husaberg it will lead you to the chassis thread where there is a write up for the most part done by the man who made a few wheels.

I had this Dave brought them up on a previous thread they belong here more then the 2 stoke thread.

interesting stuff bellow the breasts as well 3 vs 5 spokes alloy vs carbon fibre why the original Astralights were stopped, solid vs spoked etc

While we are on the subject of wheels. Any ideas on a cush drive i have come up with a few but the main question is do i really need a cush drive on a 100cc bucket?
The rim i am using is an adapted 3.5x17 front wheel.

below is a few ideas i have stolen. My original idea was similar to the Aprilia and the bottom one.But now i see the SL100 Honda had bolt on pegs i kind of are leaning towards an hybrid of them both system.
http://www.emotouk.com/mvagusta/cushdrive/cush_lrg2.jpgMV Agustahttp://i44.tinypic.com/206d2fo.jpghttp://i41.tinypic.com/33p52r7.jpgAprilia 125http://www.stevemaney.com/products/Cush%20drive%20unit.jpgTriumph Steve Manley
http://www.oppracing.com/images/uploaded/160182_sprocket_carr_p62662_062b1e.jpg Opp racing Cant remember for whathttp://www.davidsilverspares.co.uk/graphics/parts/41241222000P_large.jpgHonda ss125http://i139.photobucket.com/albums/q320/bmcdonau/SL100/Picture1283.jpgSl100 Honda http://images.wemoto.com/full/CUSH_DRIVE/10014611.jpg Rz250 Yama http://www.3upracing.co.uk/images/TZR3MA-YPVS/PC150253.JPG3 up racing for rz350

[Yow Ling]

Rich is expendable. We should get him onto producing carbon wheels for us bucket racers.

He'd probably make yours 18"

[Henk]

He'd probably make yours 18"

No matter what he did mike would claim it was too big.

[bucketracer]

While we are on the subject of wheels. Any ideas on a cush drive i have come up with a few but the main question is do i really need a cush drive on a 100cc bucket?

Dads 74 TZ350 did not have a cush drive in the rear wheel, only in the clutch.

[husaberg]

Dads 74 TZ350 did not have a cush drive in the rear wheel, only in the clutch.
Did it have spoked wheels? i always assumed they would give a little.

I have read some stuff on the net that suggest the system i origional wanted to use.
An oversize hole with a rubber metal bush and stud direct to the wheel was used on Morris mags in the 70's with a sandwich plate to stop the wobble of the sprocket,
but this system reputably on lasts 100 miles or so. On the site i was on the guy binned them and reported no problems with solid mounting on cast wheels with H1 Kawasaki's.

[bucketracer]

did it have spoked wheels? I always assumed they would give a little.

263652

73-74 tz350

263656 263657 263655

[husaberg]

263652

73-74 tz350


I know they did STD but race bike's are rarely std for long:laugh: Like those front brake although they were great. they used to biff em.
Come to think of it no TZ350 would have come with anything but wire wheels std.

This is the system (attached below) Mostly (Sl100 Other are similar) plus a acesory flange for RS125 with marchesi? -sp wheels i have came up with using as many Honda parts as possible.:msn-wink:

The other is the Uniflow 100 from years back maybe someone can explain it for Frits and the other non Kiwis the story behind it's construction?

There was a new arrival at Husaberg Manor this afternoon. it is so tasty it looks like someone has taken a chunk out of one of the chassis rails:eek:

Thanks Crazy scott Bert and Muzza B for sorting the freight i will sort you out for a Beer or Three when she makes the track.( maybe a Chocky fish as well)

[richban]

No matter what he did mike would claim it was too big.

funny coz its true.

Mikes would be a little brittle.

[richban]

While we are on the subject of wheels. Any ideas on a cush drive i have come up with a few but the main question is do i really need a cush drive on a 100cc bucket?
The rim i am using is an adapted 3.5x17 front wheel.



Sketchy runs a front on the back of his bucket with no cush and a mountain bike rear break. He has no problem going super fast.

[Kickaha]

Sketchy runs a front on the back of his bucket with no cush .

There was a guy down here a few years back doing the same, didn't cause him any problems

[Frits Overmars]

Frits what is the life span of the CF rims, and how well do they perform when someone hits a pot hole or ripple strip?I don't know. But I would steer away from second-hand rims, both carbon-fibre and magnesium. You never know what they've had to put up with.

I did take a look at your chassis thread; haven't had time to read the full 18 pages yet, but I certainly will.
The Waddon frame is not bad but I think it could do with more direct (rigid) connections between the steering head and the outsides of the sing-arm axle.
I would definitely prefer building a new frame rather than cutting up an existing one. As an example of a simple, light, easy to build and rigid frame I would suggest the layout below. Frames like this one are used in German 50 cc and 85 cc races. So far, perfect score. Notice the rake angle and the forward mass distribution.

[jasonu]

but the main question is do i really need a cush drive on a 100cc bucket?


No
10charact

[Yow Ling]

Hey TZ instead of cutting the frame on your bucket , here is a 3LN already modified

http://www.trademe.co.nz/motors/motorbikes/parts-for-sale/complete-engines/auction-473732600.htm

[kel]

There was a new arrival at Husaberg Manor this afternoon. it is so tasty it looks like someone has taken a chunk out of one of the chassis rails:eek:


Hmm seems you're a bit further on than me
263668
Guess I should pull it out from under my desk and get on with it.
Oh and a big thanks to Leed for putting me on to a Japanese proxy bidding service, I now have several parts I was unable to source in NZ:niceone:

[Moooools]

Hmm seems you're a bit further on than me
263668
Guess I should pull it out from under my desk and get on with it.
Oh and a big thanks to Leed for putting me on to a Japanese proxy bidding service, I now have several parts I was unable to source in NZ:niceone:

I have that swingarm for you. It has that missing spacer on it. Are you coming to the next Mt Welly Meet?

[2T Institute]

The Waddon frame is not bad but I think it could do with more direct (rigid) connections between the steering head and the outsides of the sing-arm axle.
I would definitely prefer building a new frame rather than cutting up an existing one. As an example of a simple, light, easy to build and rigid frame I would suggest the layout below. Frames like this one are used in German 50 cc and 85 cc races. So far, perfect score. Notice the rake angle and the forward mass distribution.

Any more pics or a website for this bike Frits?

[jasonu]

Hey TZ instead of cutting the frame on your bucket , here is a 3LN already modified

http://www.trademe.co.nz/motors/motorbikes/parts-for-sale/complete-engines/auction-473732600.htm

Ahhh the short wheelbase version...

[F5 Dave]

Ahhh the short wheelbase version...

yes, designed for quick turn-in. But obviously not quick enough for the previous owner.

[husaberg]

I don't know. But I would steer away from second-hand rims, both carbon-fibre and magnesium. You never know what they've had to put up with.

I did take a look at your chassis thread; haven't had time to read the full 18 pages yet, but I certainly will.
The Waddon frame is not bad but I think it could do with more direct (rigid) connections between the steering head and the outsides of the sing-arm axle.
I would definitely prefer building a new frame rather than cutting up an existing one. As an example of a simple, light, easy to build and rigid frame I would suggest the layout below. Frames like this one are used in German 50 cc and 85 cc races. So far, perfect score. Notice the rake angle and the forward mass distribution.
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=263666&d=1336923799
Its really Cotswolds thread he had one, years ago when he was faster:chase:
Yes like all frames the Spine is a compromise. esp in the areas you mention the space frame/Ladder/Lattice is a far better compromise of course.
But not so simple to fabricate for the motals (amateur.)
The Wandon frames depicted are largely deigned for the Rotax tandam twin (for the most part) so i think the engine can be further forward with a straight connection to the steering head on a single (disk Valve) with a longer steering head and some judicious re-angling for more forward bias.

Lastly anyone out there with any experience running 2.5x17 and 3.5x17 rims in a NF4 chassis?:scratch:

[Buckets4Me]

for those older gents that dont have Facebook

Av qualified on pole for the first round of the italian womens championship

263680263682
"Got a trophy before even racing lol starting from pole for the first round of the italian womens championship tomorrow.
Have some work to do in the cbr cup though from 26th! Crazy competitive class! Maybe rain tomorrow"





but not everything went her way




"Well that didn't end well.."
"Avalon Biddle (https://www.facebook.com/avalon.biddle) Goodbye misano!! I dont want to see you, your crappy weather or your gravel traps for a while thanks :( "


263681


From Wil Sport Management
Not a good day at the office. Full report to come but the rains came down and carnage ensure. Put it this way. In qualifying 6secs seperated the first 30 riders. The race was won about 12 secs from 2nd place and over a minute to 3rd!!! A third of field crashed including our two riders but Avalon did pick up her bike to finish 17th. She reportedly made one amazing overtaking manouvre - but was sliding down the track on her back at the time!! Lets wait for the report once battered egos have recovered. No injuries so that's the main thing.





Here is a brief run down from the weekend from Avalon.
What an eventful weekend at misano! The testing we had done here paid off and i felt good in the scorching heat during practise and qualifying, dropping my times by nearly a second every time i went on track. Saturday qualifying saw me in first position for the italian womens championship, and 26th in the cbr cup class. I turned a few heads as i was presented with a trophy for qualifying in pole position and when they handed me the microphone to give a speech i blurted out ''yeah i'm stoked!'' in a big kiwi accent. Memo from Fred: italian's have no idea what 'stoked' means.

A dramatic change of weather on sunday brought rain and strong winds, making Travis and i feel almost at home. We both were having a fantastic ride and had made it up to 10th and 11th place respectively before a 5th gear high-side threw me over the bars at around 200km p/hr. Fortunatley the bike and i were remarkably unscathed, and even smiling, as i managed to get back on and pass 4 or 5 riders to finish in 17th position.

A great start in the womens race left me out front for a lap and then running in second place until 3 laps from the finish my front wheel washed out under brakes. The bike was still upright when it happened so i was understandably annoyed to come away with no points. Redemption is on the cards for the next round at vallelunga.

A huge thanks to WIL sport management and Fred Merkel for their efforts to make this awesome experience a possibilty!

[F5 Dave]

oh well its late on a monday night & its quiet in here. I've just realised I haven't posted a musical interlude for 100 pages or more, as that seems to be my only sensible contribution I don't want to slack on my responsibilities.

However tonight's flavour is decidedly silly.

http://www.youtube.com/watch?v=pdXOudPCydM&feature=related

[Frits Overmars]

Any more pics or a website for this bike Frits?I am not at liberty to post the drawings. But you may find some pics here: http://www.simson-rennteam.de/

[breezy]

more interludes dave...... more interludes

[F5 Dave]

in another 88 pages.

[wobbly]

The music vid may seem silly - unless you know why it was done by Maynard.
But forget the vid tarts - watch the whole DVD and check out the bass player in heels - im in love.

[F5 Dave]

Yeah I've read some of the spiel ages back, but I tend to lose interest in celebrities & their distorted views on life. To the point where it wasn't till I saw the vid for weak & powerless (when released, by chance) that I thought Gee the vid looks like a bit too much like a Tool Vid. . . hold on a min, maybe it sounds like the same singer. oh Duh! Had the previous CD for years & never noticed. I had decided I didn't care too much about the bands, just their output, so why waste my time. Must be getting old.

[wobbly]

Specific Time Area sounds like a album title Tool could do - I hope to get to see Maynard at his winery soon, so will suggest it to him.
They might consider putting out a Blue Ray with a STA app on it, certainly sell more than Neels has of EngMod2T.

[Farmaken]

More questions for the wise ones,
How good does the seal around the butterfly need to be : should there be clearance to allow for expansion of the flap ??
How critical is it to have the butterfly open into the ex, stream? ( mine is going to be about 5mm from the inside wall of the header when open and close to 10 when closed )

[husaberg]

More questions for the wise ones,
How good does the seal around the butterfly need to be : should there be clearance to allow for expansion of the flap ??
How critical is it to have the butterfly open into the ex, stream? ( mine is going to be about 5mm from the inside wall of the header when open and close to 10 when closed )


I am not wise but if you have a look on Ebay Cr125 about 1986 there are plenty. Remember it opens Parallel to the flow as well not into it.

IE with the butterfly offering as little as poss restriction to the flow as possible.
You can bet big money Honda did a fair bit on testing to come up with there configurations for the std bikes.The bottom one has a spacer to increase volume.

http://i.ebayimg.com/t/Honda-1986-CR-125-Cylinder-ATAC-Power-Valve-Exhaust-Manifold-Chamber-/00/s/MTA2NlgxNjAw/$(KGrHqNHJEgE8oY,psQNBPToW+Jdi!~~60_57.JPG
NS400r not so many aroundhttp://nwracing.no/snaps/atac02.jpg
Atac valves



Honda obviously found out how to make these things work just as I did.
As short a connecting tube as you can get, diameter about 1/2 the header,ATAC vol about the same as the cylinder swept vol.
We had about 1/3 of the throttle plate hanging down in the header when it was open, in line with the flow direction.
By experiment you find the point where the resonating volume starts to kill power, and then go back a couple of hundred rpm, and snap it shut with a rpm driven solenoid.
Easy with the Ignitech programmable output.
There is NO advantage to ramping the closing point ie interconnecting it with the PowerValve is nowhere near as effective as a single point solenoid action.
Spencers Honda 500 Triple had two of them on the outer pipes, and it was completely unrideable without them.
You could get even better useable band width by having a double volume system, where another plate valve opened and shut the entrance to a second bottle vol.
The two being open initially, then the second vol being shut off, creating a much smaller vol that was then shut of at a higher rpm.
But hey the simple thing works a treat on engines with no option for a PV.


I posted about this a while ago.The chamber needs to be about the swept vol of the cylinder.
When its big enough, going bigger does nothing.
The connecting tube should be about 1/2 the header dia, as short as possible, with the controlling throttle plate as close to the pipe as you can get it, and as close to the flange as you can get it.
The resonant effect works up to a specific rpm, then kills power real quick, so you need an rpm "switch" to control a solenoid that quickly snaps the plate open at a set point,unlike a powervalve that can be ramped.
Many current cylinders have an ATAC volume within the casting that is opened/closed at the same time as the powervalve. This is easy but for sure not the best setup.



To increase low end power Wobbly has pointed me towards the Honda ATAC system, he tells me that they had some success with the idea on the BSL500. He sent me this picture and some pointers on where to put it on the header.

241414

"As close to the flange as you can, and get the throttle plate as close to the header as you can to reduce the ill effects when its closed at hi rpm......... Wob"

Other Bits and Bobs about the ATAC system that I scraped from the net........

ATAC System: The Honda Automatic Torque Amplification Chamber system works by effectively increasing or decreasing the volume of the exhaust system with a small butterfly valve located just before the exhaust connection.

A few pictures here:- http://www.scooterhelp.com/moto.barrels/honda.cr250.84_85.overview.html
A bit of YouTube of a guy working on his ATAC http://www.youtube.com/watch?v=tY7D0jLcfws

Atac and vtac differ very little. Vtac is a resonator chamber like kips, with only one inlet/outlet where atac is a bypass chamber with a in and out yet it doesn't block the main exhaust flow even when open so it very much acts like a resonator.

241367 241376

[ATTACH=CONFIG]241373[/ATTACH
[QUOTE=wobbly;1130095382]
In the testing I have done, the volume of the resonator chamber isnt critical, once you have reached a certain size.The best place to start is equal to the cylinder displacement, and this will "work" every time.
Fitted to a world champ ski engine, these chambers, operated by a flat, throttle slide plate,added over 30% more power at 1/2 peak rpm.
They seem to work very similar to a PV, in that the pipe effects are dramatically reduced in the area where the wave action is way out of phase with the port.
This is seen in the sim, and on the dyno, in that you can change the pipe dramatically, and it has little effect when the PV is down, or the chamber is open.

I simply dont "get" the correlation between bmep and Ex gas mean temp at all.
It is entirely possible to set up an engine to produce X - Hp at just about any reasonable mean temp.
The gas temp affects the pipe dynamics, and is a function of the static compression, the ignition advance, and just as importantly the dynamic compression ( that is achieved by the delivery ratio X the trapping efficiency).
We can achieve the same power using unleaded fuel running very rich with lots of advance and no com, this would give a header temp of say 1050F.
On leaded Avgas, the tuning combination would be very different , but the header temp for best power on that fuel would need to be over 1200F.

You use the bmep to correlate the port STAs with the Hp target.
The pipe temp is a separate function that dictates the pipe length needed to work with the Ex duration you have derived from the STA calcs.
The 9 Bar engine can be run at 500C or 600C, it all depends upon the tuning approach, and the fuel used, as to what the mean temp in the pipe ends up being.



My thoughts,from the testing I did with a PV and ATAC operated separately ( instead of combined together as many MX engines have now) is that this works real well with no down sides at all,and is easy to implement..


OK, here is some info on how to utilise the servo option on the Ignitech.
The servo has 5 wires, two are 12V +/- and the other 3 are the servo feedback positioning pot.
Always wire the two functions on separate plugs.Once you have the servo connected to the blade or whatever, disconnect the servo motor power plug.
Then on the screen you will have a readout for the servo position, as mV or as a % if using the RACE box.
I have never used the % option so here is how to program the mV setup.Drive the servo to the travel limit ( in, or down or whatever) by gripping the servo wheel with vise grips.
Cycle it back and forth a few times to get an accurate position that takes up any small slack in the cables.Note down the "servo measured" value on the screen.Then wind the servo around to the opposite limit, note this value down.
Then in the servo screen you can enter the two values of fully up, and fully down, with an rpm span between them.
Use a few of the extra points in between, so you can, if needed, force a non linear movement with rpm ie not a straight line.
Hit program, turn off the ECU,turn it on again, and it will cycle up and down,as it has been programmed.
You can check the up and down positions and compare the "servo measured" to the "servo desired" on screen, in real time.
The hysteresis should be set usually at around 100mV, less will speed up the response, but go too low and the servo will "hunt" around the values programed.
The RZ servos are all getting old and shagged - the newer R1 servo is mechanically very similar but uses a special molded in plug - I have the right ones to match.
The R6 and ZXR ones are not as well made, the shaft isnt supported at both ends properly.
Here is a sample wiring setup and a PV curve, set to start opening at 7200 and full open at 9000, with about 1V of span between.
You could use this to rotate a spool like an RZ, a blade like a flat PV or even the 1/2 throttle plate if you wanted to.




The cylinders that use the powervalve action to open and close a port linking to a chamber within the casting are very limited by physical room.
We tested a couple of sizes of connecting tube and plate valve, and found that if it was smaller than 1/2 the header dia it didnt work near as well.Bigger than that and the flow disruption lost top end power.
We had a 20mm tube on a 43mm header for the 166cc cylinder size, with a 150cc chamber, and as I said this gave around 28% more power just below where the valve closed.

From reading Blair, I had formed the impression that mean ex temp was directly related to BMEP.

But a moments thought would have shown me that its not as close a correlation as I had thought.

I was reminded by your post that the ex temp can also be affected by fuelling and ignition advance (amongst other things).

And of course on our own engines we are retarding the ignition and leaning out the mixture by closing the electric power jet so as to heat the ex gas in the pipe and thereby extend the over rev.

[crazy man]

I know they did STD but race bike's are rarely std for long:laugh: Like those front brake although they were great. they used to biff em.
Come to think of it no TZ350 would have come with anything but wire wheels std.

This is the system (attached below) Mostly (Sl100 Other are similar) plus a acesory flange for RS125 with marchesi? -sp wheels i have came up with using as many Honda parts as possible.:msn-wink:

The other is the Uniflow 100 from years back maybe someone can explain it for Frits and the other non Kiwis the story behind it's construction?

There was a new arrival at Husaberg Manor this afternoon. it is so tasty it looks like someone has taken a chunk out of one of the chassis rails:eek:

Thanks Crazy scott Bert and Muzza B for sorting the freight i will sort you out for a Beer or Three when she makes the track.( maybe a Chocky fish as well)oh yum a chocky fishy . were did you find the gp wight up even has my name in the b grade

[husaberg]

oh yum a chocky fishy . were did you find the gp write up even has my name in the b grade

I will fillet the Chocky fish myself as well.
But scott Aren't you still in B grade:laugh:

It was in Kiwibiker August 1994 i kept most of the old mags.

But I can't find the one that has the write up mentioning me dueling With GSX1100's on my road race debut with my awesome 197 1954 James .(USD forks)
It said something corny along the lines i was a rider to watch in the future. Well apologies if you have watched cause it must have been very disappointing for you:shit:
Still waiting for a GP ride actually. My only prerequisite is i ain't riding no Yamaha's (even if Kenny come begging again) Cries like a baby and stomps his feet BTW:chase:

[wobbly]

The throttle plate or whatever you design must seal well.
I did a sliding flat plate with a hole in it design like they use in fuel injection throttle plates, that worked well on Champ winning jetski, as this got the plate real close
to the header and there was very little flow disruption when closed.
A small leak into the cavity will kill power real quick with an ATAC system.

[crazy man]

I will fillet the Chocky fish myself as well.
But scott Aren't you still in B grade:laugh:

It was in Kiwibiker August 1994 i kept most of the old mags.

But I can't find the one that has the write up mentioning me dueling With GSX1100's on my road race debut with my awesome 197 1954 James .(USD forks)
It said something corny along the lines i was a rider to watch in the future. Well apologies if you have watched cause it must have been very disappointing for you:shit:
Still waiting for a GP ride actually. My only prerequisite is i ain't riding no Yamaha's (even if Kenny come begging again) Cries like a baby and stomps his feet BTW:chase:yip still just a b grader went up the ladder just to go back down )-: looks like you better sleve the james to a 125 for a bucket lol my brother has one of them with no front breaks so l know how good they handle ..:first:not good

[husaberg]

yip still just a b grader went up the ladder just to go back down )-: looks like you better sleve the james to a 125 for a bucket lol my brother has one of them with no front breaks so l know how good they handle ..:first:not good

The James was already a little over the 197 225cc or so alloy fins shrunk on 1 5/32 Anal carb and Expansion chamber .
If alas noise did indeed =HP it would have been a real powerhouse with 123 dB at Levels 3/4 throttle.:eek: Oh yes
No damping no handling No brakes we put on a larger brake and it was even worse 19 inch super skinny rims plastic tires.

I always wanted to do a Villiers based rigid for Cust with a Honda based Top end Especially to go hunting Manx's and 7R's.
Talking to Grumph it looks like he did build one.

[Grumph]

The James was already a little over the 197 225cc or so alloy fins shrunk on Expansion chamber 19 inch super skinny rims plastiwoulf have been a real powerhouse 123 dB at levels 3/4 throttle.:eek:

I always wanted to do a Villiers based rigid for Cust with a Honda based Top end Especially to go hunting Manx's and 7R's.
Talking to Grumph it looks like he did build one.

Yup - and the mark one was a three speed rigid which seriously embarassed CB350's at an early CAMS meeting...before dropping the bottom out of the Villiers gearbox. The Mark 2 is a 4 speed spring frame which last time out - some years back - murdered the Ducati 250's before seizing as was inevitable...all on basically (very basic) a 197 6E. One day I'll drag it out an put it on alky and make up a belt primary for it too.

But you've never seen that Husa - what you've seen pics of is the Starmaker powered bike just finished and still sorting out.

[gav]

Talking about old bangers doing the business, check this out!
A 30 + year old frame with a home brewed modified farm bike engine cleans up NZ1 bucket champs and skinny speedsters Nick Cain and Ali Hoogie. He also won the race including a full field of 150SS and 250 Pro Lites.

[Yow Ling]

Talking about old bangers doing the business, check this out!
A 30 + year old frame with a home brewed modified farm bike engine cleans up NZ1 bucket champs and skinny speedsters Nick Cain and Ali Hoogie. He also won the race including a full field of 150SS and 250 Pro Lites.

Who is he ? Jesus ?

[gav]

Who is he ? Jesus ?
He just might be .... think he went to school with him anyway ...

[husaberg]

He just might be .... think he went to school with him anyway ...
Really he might know Grumph he went to school with Moses. He sat next to him in Masonry classes:msn-wink:
Thats him third from left at the back looking bored.
http://www.answersingenesis.org/assets/images/articles/am/v3/n2/adam-violation.jpg


Jesus's dad! look like a rather portly chap........fat stig?

I guess we may know who ate all the last supper then?


Yup - and the mark one was a three speed rigid which seriously embarassed CB350's at an early CAMS meeting...before dropping the bottom out of the Villiers gearbox. The Mark 2 is a 4 speed spring frame which last time out - some years back - murdered the Ducati 250's before seizing as was inevitable...all on basically (very basic) a 197 6E. One day I'll drag it out an put it on alky and make up a belt primary for it too.

But you've never seen that Husa - what you've seen pics of is the Starmaker powered bike just finished and still sorting out.

What a 6E gee haul yourself into the 50's Greg:eek:
i had a 8E and Four Speed. I would have said about the four speed but I didn't think having four speeds would impress anyone other than the Vespa tuner:laugh:
I forgot to mention it still had the original huge Brass flywheel as well for the inertia mind you.

Do you want me to post the pics of the Starmaker special.?

[Buddha#81]

Jesus's dad! look like a rather portly chap........fat stig?

[gav]

Actually he mentioned Jesus several times when he was talking about his front suspension too ! :shifty:

[diesel pig]

I am not at liberty to post the drawings. But you may find some pics here: http://www.simson-rennteam.de/

That's some real interesting stuff Frits. I see that the engine uses a crankcase reed is that to help widened the powerband because of the 5 speed gearbox? or is cause it is
not possible to fit a disc valve to the cases?

[Frits Overmars]

That's some real interesting stuff Frits. I see that the engine uses a crankcase reed is that to help widened the powerband because of the 5 speed gearbox? or is cause it is not possible to fit a disc valve to the cases?It is very well possible to fit a disc valve to those Simson engines; it has been done on both sides of the engine (though not yet both on the same engine).
But the side-reed cases were readily available and they make sufficient power to win, though I keep saying I hate them; side reeds combine the worst of both worlds.

[richban]

Talking about old bangers doing the business, check this out!
A 30 + year old frame with a home brewed modified farm bike engine cleans up NZ1 bucket champs and skinny speedsters Nick Cain and Ali Hoogie. He also won the race including a full field of 150SS and 250 Pro Lites.

So who is it then. Top effort.

[kel]

So who is it then. Top effort.
That would be Brendan on his KE/RG hybrid now housed in an old RG250 chassis (well going by the bike number anyways).

[F5 Dave]

yep, strike one up for us old fat blokes! :niceone:

[richban]

That would be Brendan on his KE/RG hybrid now housed in an old RG250 chassis (well going by the bike number anyways).

Thats funny I always thought he rode like a pansy flower lawn blows sort of sissy man. :msn-wink:

[2T Institute]

I am not at liberty to post the drawings. But you may find some pics here: http://www.simson-rennteam.de/

Thanks for that a load of inspiration there. I see from the youtube clip it gets along nicely. Though the gearbox seems to do it a bit tough on the downshifts.

http://www.youtube.com/watch?v=gQKXmL8AKYE&feature=related

[timg]

Thats funny I always thought he rode like a pansy flower lawn blows sort of sissy man. :msn-wink: Haha :laugh: You'll be getting the Bren bash at the BOB :bash:

[husaberg]

Thanks for that a load of inspiration there. I see from the youtube clip it gets along nicely. Though the gearbox seems to do it a bit tough on the downshifts.

http://www.youtube.com/watch?v=gQKXmL8AKYE&feature=related


He is practically able to hold inch perfect lines nearly every time and is seemingly able to dive up the inside at will. Clever and sorted.
Although some of the backmarkers may not be so polite in NZ.:msn-wink:

[cotswold]

yep, strike one up for us old fat blokes! :niceone:

on a smokie

[Kickaha]

Not even remotely bucket related but a cool two stroke all the same and up for sale

http://i458.photobucket.com/albums/qq303/16000rpm/DSCF1764.jpg
http://i458.photobucket.com/albums/qq303/16000rpm/DSCF1763.jpg

http://www.ozebook.com/compendium/suzipics/sparton.html

[Yow Ling]

Something flash turned up in the post today

263821263822263823

its the rarest of rare bucket parts, an exhaust nozzle for the rgv100, thanks Wob its way more exotic than I imagined,

There were 2 in the packet , I had a visitor from Auckland today , now theres only 1 in Chur chur

[husaberg]

Not even remotely bucket related but a cool two stroke all the same and up for sale


Barry Hart had a few "world beaters" like this was one. He had a bit to do with Armstrong as well as the "silver dream racer" .
The designs were always seemingly over hyped up by a British media starved for success. Which was a shame because they were decent if not that innovative designs OK he borrowed a fair bit.
I seem to remember there was a much more successful Dutch 3 cylinder TZ350 and a home build three from the south island Grumph has mentioned.
I have an article that will will post when i can be arsed looking for it.
http://yorkshireferret.blogspot.co.nz/2012/02/barton-motors-sparton-phoenix-and-more.html

http://armstrongfactoryracing.com/history.html

Armstrong Motorcycles began in the late 70's when Armstrong Industries bought up CCM (Clews Competition Motorcycles) then later, Cotton Motorcycles and Barton Engineering. These smaller companies were amalgamated to form the best motorcycle engineering brains and knowledge at the time this side of Japan. Terry Wilson's Cotton had developed a super fast 250cc machine, initially produced with a one-off L-twin 250cc Rotax engine which was especially built for Cotton. This engine was developed by Rotax, and went on to become the infamous Type 256 inline twin. The first CCM Armstrong 250cc racers were essentially rebadged Cotton's, with a more "TZ-esque" frame designed by Mike Eatough, incoporating a vertical rear shock design.
Rotax 256 250cc engines were used initially but in 1981 an improved designed was developed in house by Armstrong Technical Director, Barry Hart (ex-Barton Engineering) including horizontally split crankcases, improved porting, cooling and individual cylinder heads. Initially developed as a 350cc the CM36 engine was used in both 250 & 350cc guises for the works machines. Several variants were produced, with the last model being updated in 1983, which featured 180 out of phase cranks, instead of the usual counter rotating cranks with both pistons rising and falling at the same time

Phoenix (silver dream racer) wow never realized the Buell connection later.
http://farm4.static.flickr.com/3474/5713835926_2af9cf198b.jpghttp://farm3.static.flickr.com/2318/5713261219_87f2b27577.jpghttp://farm3.static.flickr.com/2798/5713831798_df2b6f2d85.jpghttp://star.walagata.com/w/sundialmotosport/3.jpg
http://www.flickr.com/photos/85689738@N00/5713273745
http://www.flickr.com/photos/85689738@N00/5713261305

[TZ350]

263837

Ok ... Chambers bike is lighter than mine.

Checking the relative weights of the wheels, as spoked wheels are supposed to be lighter.

263833 Front wire wheel 9.0kg

263832 Rear wire wheel 9.5kg

263835 Front FZR wheel 9.0kg

263834 Rear FZR wheel 12.0kg

263831 FZR sprocket carrier 2.5kg

Not as much difference as I had expected. Only 2.5kg and that was all in the back wheel. How to loose the equivalent of the sprocket carrier, use a wide front from some other bike and fixed alloy sprocket perhaps. And replace the rear caliper with something lighter.

[husaberg]

263837

Ok ... Chambers bike is lighter than mine.

Checking the relative weights of the wheels, as spoked wheels are supposed to be lighter.

Front wire wheel 9.0kg
Rear wire wheel 9.5kg

Front FZR wheel 9.0kg
Rear FZR wheel 12.0kg
FZR sprocket carrier 2.5kg

Not as much difference as I had expected. Only 2.5kg and that was all in the back wheel. How to loose the equivalent of the sprocket carrier, use a wide front from some other bike and fixed alloy sprocket perhaps. And replace the rear caliper with something lighter.

From Memory Nudemetals said a long time ago that FZR400 front wheel (possibly other Yams as well) takes a DT175 sprocket direct.

You can always do what I did and use a 3" x 17" FZR (400?) front rim on the rear.
Sure you don't have a cush-drive (rubber blocks) but not that important on a bucket and I found that DT175 sprockets fit perfectly onto the disc bolt pattern.
Only issue I found was it was a tight squeeze onto the swingarm of the RGV150 frame but that's the frame's fault !!!

(I use a 3MA TZR front rim on the front).

The ones i chose are Well Honda
HONDA CBR 400 NC23 FRONT Wheel 3.5X17
HONDA CBR 250R MC19 2.5X17
I think the 3.5 (NC23) is actually lighter than the 2.5 (MC19). The later 6 spokes are lighter than my 3 spokes i think.

[TZ350]

Geee those bare wheels don't weigh much.

Std RS front 6 lbs or 2.7kg and rear 7 lbs or 3.2 kg.

Conversion assistant http://www.convertunits.com/from/lbs/to/kg

I weighed a set of RS wheels with disk tire sprocket etc.

RS complete Front wheel 8.0kg complete Rear wheel 9.5kg

compaired to:-

Wire complete Front wheel 9.0kg complete Rear wheel 9.5kg
FZR complete Front wheel 9.0kg complete Rear wheel 12.0kg


Complete RS swing arm 3.5kg and FZR swing arm 4.5kg.

Although I am not that convinced about the accuracy of bathroom scales for measuring anything, they at least give an indication of the wheels relative weights.

I might have a FZR400 front, I will dig it out and have a look.

[husaberg]

Geee those bare wheels don't weigh much.

Std RS front 6 lbs or 2.7kg and rear 7 lbs or 3.2 kg.

Conversion assistant http://www.convertunits.com/from/lbs/to/kg

I weighed a set of RS wheels with disk tire sprocket etc.

RS complete Front wheel 8.0kg complete Rear wheel 9.5kg

compaired to:-

Wire complete Front wheel 9.0kg complete Rear wheel 9.5kg
FZR complete Front wheel 9.0kg complete Rear wheel 12.0kg


Complete RS swing arm 3.5kg and FZR swing arm 4.5kg.

Although I am not that convinced about the accuracy of bathroom scales for measuring anything, they at least give an indication of the wheels relative weights.

I might have a FZR400 front, I will dig it out and have a look.

down side of cast wheels on a supermoto?
Note this compares std size which i think is 3 and 4.5 inchx17
http://http://motard-supermoto-wheels.sportsontheweb.net/index.htm (http://motard-supermoto-wheels.sportsontheweb.net/index.htm)
Aren't cast wheels a lot heavier? The common complaint is extra weight with cast wheels, but with CBR250 wheels (CBR250R & CBR250RR specifically) this is not true. We've weighed the CBR wheels, fully kitted out with tyres, discs and sprocket, against typical quality motard spoked wheels using Talon hubs and Morad rims. The results?:
CBR250r wheels complete with disks tires spockets etc .
Front spoked wheel: 11.1 kg 3-spoked cast wheel: 10 kg 6-spoked cast wheel: 10.5 kg
Rear spoked wheel: 13.1 kg 3-spoked cast wheel: 13.8 kg 6-spoked cast wheel: 13.9 kg


A std ZXR750 front wheel from the 90's is 4.5 KGs (bare weight)
Most of the weight saving from aftermarket wheels (up to 46% in the article i have here) is that most weight saving come from the rear with only approx 1 kg able to be lost off the front. Compared with a 4.0kg wheel vs 7.64kg oe for the rears.

SO it looks like my gut feeling of the 3 spoke vs the 6 spoke is wrong if at least on these the 3 spoke is lighter WTFIUWT
Although it may be because my front is a MC19 and is not hollow spoked?

[richban]

263837

Ok ... Chambers bike is lighter than mine.

Checking the relative weights of the wheels, as spoked wheels are supposed to be lighter.

263833 Front wire wheel 9.0kg

263832 Rear wire wheel 9.5kg

263835 Front FZR wheel 9.0kg

263834 Rear FZR wheel 12.0kg

263831 FZR sprocket carrier 2.5kg

Not as much difference as I had expected. Only 2.5kg and that was all in the back wheel. How to loose the equivalent of the sprocket carrier, use a wide front from some other bike and fixed alloy sprocket perhaps. And replace the rear caliper with something lighter.




I reckon bite the bullet and get some proper wheels.

263841


Front 7kg

Complete rear with sprocket carrier 7.2kg


263842


If you had some of these you would lose just under 7kg. The Honda ones weigh the same.

[TZ350]

OK ...... I am up for two Honda RS125 17x2.5 fronts and two 17x3.5 rears.

Failing that two matching 3.5"x17" fronts from the Suzuki GSXR range or Honda CBR for adapting to the back of the Beast.

Good idea using a front on the rear, thanks Husa, Rich, Sketch and Kick for the heads up.

[gav]

OK ...... I am up for two Honda RS125 17x2.5 fronts and two 17x3.5 rears.

Failing that two matching 3.5"x17" fronts from the Suzuki GSXR range or Honda CBR for adapting to the back of the Beast.

Good idea using a front on the rear, thanks Kick.
I'm surprised you havent built your own carbon fibre wheels yet? sheesh ... :cool:

[TZ350]

<iframe src="http://www.youtube.com/embed/FZ8CGGYamuE" allowfullscreen="" frameborder="0" height="315" width="560"></iframe>

Interesting clip on pipe building, I often wondered how they get those nice neat welds.

[Kickaha]

Interesting clip on pipe building, I often wondered how they get those nice net welds.

The guy who did my chambers for Superkart did them the same way, the pipe on my Bucket was as well

[F5 Dave]

Yeah I was going to mention Eric Buell bought the whole shooting match off Barton. Found out everything was pretty crap & tried to make it work. Obviously desperation made him rethink the situation & make bikes with sewage pumps.

[Farmaken]

So this is where I am up to so far, Butterfly valve seems to be a long way from the header ID so plan B is to make up a spool valve like a Yamaha power valve and fit it in the same place as the collar which is currently on the header so that the OD of the spool is flush with the header ID when closed .:blink:
263880263879263881

[TZ350]

That looks good, great to see the pictures, I am looking forward to seeing how it goes as I want to try making one myself.

These Honda ones seem to have the blade opening across the pipe and others in line with the header. There also looks like a small distance between the header and butterfly.

I remember Frits said its best to have the butterfly blade opening in line with the pipe as you don't want it disrupting the gas flow or getting over heated.


Opening the blade across the flow would have three big disadvantages. It would be much more of a disturbance to the flow, it would heat up the blade much more, and the flow colliding against the protruding half of the blade would constantly try to rotate it. As the flow direction is alternating so close to the cylinder, that would mean a constant hammering on the governing mechanism.

[bucketracer]

As I heard it and subject to offical confirmation.

The tide might be turning.

2-Strokes :first::second::third: in the points racing at Mt Welly yesterday, and about time ..... :laugh:

The Dominic Howe was won by Dave M riding an MB100 powered RS50 prepaired by Speedpro with a 25hp 80cc stroker runner up.

And F5 was 2-Strokes 1-2 all day long.

[TZ350]

263916

Got the head off tonight.

263917

Doesn't look to bad in there.

263918

Carefully re checking the squish.

263914

And it looks like 1mm.

So the trick is to figure out how to take 0.4mm of the top of the barrel for 0.6mm static squish.

263915

Also checked the timing to see whats needed to get the Ex opening 80 ATDC and the main Trans opening 116 and sec 114 ATDC.

[TZ350]

The EngMod2T files for STA's, Ex and Transfers for those that are interested in such things.

Even with a crazy big 38mm inlet port in this model, its still the inlet port thats limiting the power possible and even more so with one suitable for a 24mm carb.


I had a quick look at the 3Ex GP125 in Engmod.
Lifting the main Ex to 80* needs to have the B,C transfers lifted to 113.8* to get the STA near balanced again.
It will then have staggered Ex plus reverse staggered transfers,Mr Thiel would be proud.

With the finished cylinder, I will be aiming to follow Wobs advice on timing and squish best I can. But 113.8, I can't read 0.8 deg on the the deg wheel so the result will just have to be the best I can manage.

[dinamik2t]

Why use the degree wheel TZ? You can use the direct mm distance EngMod gives, 37.7mm. Take into account any pos/neg deck height, draw a line or place a barrier into the cylinder and port it that way.:innocent:
I think it's pretty easier and much more accurate when measuring with the vernier or depth calipers!

On the other hand, I am not sure what's the best way to determine a cylinder's timing. Is it the exact distance from TDC, as ported above or is it where, lowering the piston, you get a glimpse of light out of the port?

A large degree wheel would be the best, by the way:

http://image.mustangandfords.com/f/34626378/mdmp_1011_02_o+how_to_degree_a_camshaft+degree_whe el.jpg

By the way, is it ok to reveal the tuned length of the piranha pipe?

[Buckets4Me]

Why use the degree wheel TZ?
A large degree wheel would be the best, by the way:

http://image.mustangandfords.com/f/34626378/mdmp_1011_02_o+how_to_degree_a_camshaft+degree_whe el.jpg



I think they have already started filing the crash knobs away to fit the larger degree wheel

[twotempi]

What would the result be with a 100cc engine ,watercooled, with no carb size restriction.

Is that potentially a better all-round configuration ??

[F5 Dave]

Certainly it is the option Mike's MB100 is with great results (head only wc so far). Has been probably the most common F4 GP winner historically, though maybe not all WC, but plenty were.

Many were Kawi or Suzukis with home WC or RG400 barrels grafted on.


Sadly my first attempt 16 years ago leaked into the triple port due to duf welding (not mine, but might as well have been me learning).

[Buckets4Me]

What would the result be with a 100cc engine ,watercooled, with no carb size restriction.

Is that potentially a better all-round configuration ??

no one has got more than 30 H/p from one yet (that I know of)

and starting over again with a new engine :shutup: (what would Burt have said)

[husaberg]

no one has got more than 30 H/p from one yet (that I know of)

and starting over again with a new engine :shutup: (what would Burt have said)


Yet:sweatdrop

And Burt had the Velocette as well remember.
From what i understand it was the Worlds Fastest Vellocette as well.(according to Ivan Rhodes)
Not bad for a old fella from invergiggle.

[Buckets4Me]

Yet:sweatdrop

And Burt had the Velocette as well remember.
From what i understand it was the Worlds Fastest Vellocette as well.(according to Ivan Rhodes)
Not bad for a old fella from invergiggle.

and if you asked anyone they would have asked WHY and said it cant be done :shit:
or thats not the way to do it. you mow the lawn not BURN it.

I did hear that TZ is now doing somehthing different :gob: :shutup: ( still the same engine )

[TZ350]

Is that potentially a better all-round configuration ??

100cc H2O pumper, well thats plan "B" and I have box's of parts put aside just in case I have to go there.

263949


What would the result be with a 100cc engine ,watercooled, with no carb size restriction.

Well, its easy to see, here is a dyno graph of the best 100cc H2O pumper that I know of.

Speedpros 30 hp 100 compaired to several runs of my 28.9 hp air cooled 125 configuration. I like the torqe curve of my 125 better. Reliability, well it did several Mt Welly meetings and ran all day when the Bucket GP was run on the old Taupo track just before last Xmas. All that was before I swapped the cylinder for one ported for 31 hp which failed at Kaitoki.

I am having way to much fun pushing for a reliable 32-34 with an equally good power spread to want to change tacks at the moment. And if anyone wan'ts to know, those consistant 28.9 hp runs were done with a 24mm HL 360A Tillotson go kart pumper carb.

263950

Tillotson HL 360A 24mm

[kel]

I did hear that TZ is now doing somehthing different :gob: :shutup: ( still the same engine )
It's those fancy forks, they've made him go all Honda

[husaberg]

It's those fancy forks, they've made him go all Honda

It normally starts with a few Honda bits here and there and then snowballs until it ends up like (Name deleted) Er... Non Honda.
where the only Yamaha bits left is the piston.That it seem is even trying to get it self replaced as well.

[Grumph]

100cc H2O pumper, well thats plan "B" and I have box's of parts put aside just in case I have to go there.

263949



Well here is a dyno graph of the best known 100cc H2O pumper.

Speedpros 30 hp 100 and my 28.9 hp air cooled 125 configuration, I like the torqe curve of my 125, and it did several Mt Welly meetings and ran all day on the old Taupo track Bucket GP before last Xmas before I swapped the cylinder for the 31 hp unit.

I am having way to much fun pushing for a reliable 32-34 with an equally good power spread to want to change tacks at the moment. And if anyone wan'ts to know, that consistant 28.9 hp was run with a 24mm HL 360A Tillotson go kart pumper carb.

263950

That was my experience with the big MB...not a lot more HP but much better torque. This is where you may start to look hard at matching tracks to motors. The better torque of the 125 suits Kart tracks and the 100's work well on big circuits where you're on full noise most of the time - and the water cooling gives them potentially better endurance.

[Buckets4Me]

they've made him go all Honda

not bad for a Yamaha man with a suzuki bike :eek:
now what aircooled rotary valved hondas are out there so he can go all the way
I did hear that he was going back to suzuki for some bits

[TZ350]

This is where you may start to look hard at matching tracks to motors. The better torque of the 125 suits Kart tracks and the 100's work well on big circuits where you're on full noise most of the time - and the water cooling gives them potentially better endurance.

Totaly agree, its starting to look like the air cooled 125 could be good on short circuits and a water cooled 100 for the longer tracks.

[jasonu]

Totaly agree, its starting to look like the air cooled 125 could be good on short circuits and a water cooled a 100 for the longer tracks.

Maybe not.
Quote from Bucketracer

The tide might be turning.

2-Strokes in the points racing at Mt Welly yesterday, and about time .....

The Dominic Howe was won by Dave M riding an MB100 powered RS50 prepaired by Speedpro with a 25hp 80cc stroker runner up.

And F5 was 2-Strokes 1-2 all day long.

[TZ350]

Ok changed the ports and skimmed the top of the cylinder to get the squish closer to 0.6mm

All this to take 0.35mm of the top of the barrel, we do go to some trouble to get the details right.

The split ring held the cylinder central and the pull back held it secure and square in the chuck. The pull backs foot is across the main transfer ports and the threaded rod goes right through the lathes head stock and is pulled up with a nut and spacer at the back.

[Yow Ling]

So TZ , say you were thinking of making your own barrel , engine or even spacecraft. You could read this thread http://www.homemodelenginemachinist.com/index.php?topic=18727.0 and steal and adapt some of this guys rapid prototyping ideas.

[TZ350]

So TZ , say you were thinking of making your own barrel , engine or even spacecraft. You could read this thread http://www.homemodelenginemachinist.com/index.php?topic=18727.0 and steal and adapt some of this guys rapid prototyping ideas.

Thats some clever idea, and plenty of links to other casting methods, well worth a very carefull read. Thanks.

[husaberg]

So TZ , say you were thinking of making your own barrel , engine or even spacecraft. You could read this thread http://www.homemodelenginemachinist.com/index.php?topic=18727.0 and steal and adapt some of this guys rapid prototyping ideas.

That is real neat.
I guess by now most people know that is similar to how some of the patterns for the Britten V twins were done.
Except the crew used thin plywood sheets they scaled the pieces off the blueprint cross sections and glued them together allegedly:msn-wink:
http://www.britten.co.nz/info/images/infotechengin.gif

[TZ350]

Front wire wheel 9.0kg
Rear wire wheel 9.5kg

Front FZR wheel 9.0kg
Rear FZR wheel 12.0kg




HONDA CBR 400 NC23 FRONT Wheel 3.5X17
HONDA CBR 250R MC19 2.5X17




Bare Std RS Front 2.7kg
Bare Std RS Rear 3.2 kg.

Complete RS Front wheel 8.0kg
Complete RS Rear wheel 9.5kg

Wire complete Front wheel 9.0kg
Wire complete Rear wheel 9.5kg

FZR complete Front wheel 9.0kg
FZR complete Rear wheel 12.0kg

Complete RS swing arm 3.5kg
Complete FZR swing arm 4.5kg.




CBR250r wheels complete with disks tires spockets etc .
Front spoked wheel:
11.1 kg 3-spoked cast wheel:
10 kg 6-spoked cast wheel: 10.5 kg

Rear spoked wheel:
13.1 kg 3-spoked cast wheel:
13.8 kg 6-spoked cast wheel: 13.9 kg

A std ZXR750 front wheel from the 90's is 4.5 KGs (bare weight)




263841
RS Front 7kg
263842
Complete rear with sprocket carrier 7.2kg



Failing that two matching 3.5"x17" fronts from the Suzuki GSXR range or Honda CBR for adapting to the back of the Beast.

264015 264014

Bare front GSXR Suzuki 3.5"x17" 4.5kg

[F5 Dave]

Hmm, where did that GSXR wheel come from? I sold one last year on TM.

[kel]

Bare front GSXR Suzuki 3.5"x17" 4.5kg

The alloy sprockets I bought from Bill Syfan ($25NZ each) weigh approximately 300grams, add a light disc and you have a very light weight rear wheel set up.

[husaberg]

The alloy sprockets I bought from Bill Syfan ($25NZ each) weigh approximately 300grams, add a light disc and you have a very light weight rear wheel set up.

My weights had tires i think. You might want to consider one of those as well:lol:

[Ocean1]

Bare front GSXR Suzuki 3.5"x17" 4.5kg

I see Buell have shaved the front wheel on their new rig down some more.

2.45 Kilos.

[crazy man]

My weights had tires i think. You might want to consider one of those as well:lol:do you need tires in buckets did not think they make any hp to worry about them :cool:

[richban]

264015 264014

Bare front GSXR Suzuki 3.5"x17" 4.5kg

I have a 3.5 x 17 Marchesini honda front that weighs in at 2.2 kg if you have a spare $550.

[richban]

264015 264014

Bare front GSXR Suzuki 3.5"x17" 4.5kg

Just thinking about that. By the time you add the disk, mounting bolts both sides and tire it will be about 10kg. Also there is a lot of weight on the outside rim. So thats not so good. More power needed to get it spining and more breaks needed to get it stopped. That plan might not give the results you were after. But yes a set of RS wheels does not come cheap. Maybe the spoked wheel could be a better option. Just re-lace the wheel with some nice thin spokes. Can you make them tubeless?

[kel]

My weights had tires i think. You might want to consider one of those as well:lol:

Oh yeah tyre. What planet are you guys on? We're using titanium hardware and alloy disc (its just for show) the wheel's going to be seriously light

[Grumph]

The standard GSXR wheel is the starting point - it has material thicknesses designed/required for much larger and heavier bikes.
If you've got the time and a big lathe there are savings which can be made.
I saw a homemade carbon fiber rear disc in use in NZ F3 in the early 90's - it can be done and has been.
Taking weight out of chassis parts just takes time....and imagination.

[bucketracer]

Maybe the spoked wheel could be a better option. Just re-lace the wheel with some nice thin spokes. Can you make them tubeless?

Yes Chambers has been able to seal the spoke nipples and make his spoked wheels tubeless.


I have a 3.5 x 17 Marchesini honda front that weighs in at 2.2 kg if you have a spare $550.

A spare $550 nope ...... I don't think TeeZee will want to go there, especially as he will want two matching Fronts and two Rears, $2200 all up just for bare wheels.


By the time you add the disk, mounting bolts both sides and tire it will be about 10kg.

Still likely to be lighter than the current FZR 3Ln rear at 12.5kg. 2.5 kg at least, more with lighter brake and sprocket parts and a little luck. Lighter at the back was the objective.


The standard GSXR wheel is the starting point - Taking weight out of chassis parts just takes time....and imagination.

I think TeeZees plan is to gather up some readily available and not to expensive bits and bobs to see what can be done.

[husaberg]

The standard GSXR wheel is the starting point - it has material thicknesses designed/required for much larger and heavier bikes.
If you've got the time and a big lathe there are savings which can be made.
I saw a homemade carbon fiber rear disc in use in NZ F3 in the early 90's - it can be done and has been.
Taking weight out of chassis parts just takes time....and imagination.


Its an idea the only point is knowing where to stop even the experts can get that bit wrong Remember
Marvic,Robert Dunlop and the TT (there was no V4 victory from Mr Dunlop that year.)

http://www.youtube.com/watch?v=IAS11mkwXbY

http://www.youtube.com/watch?v=B6T6dTIOZ2c

I would suggest cutting one open first to see, what is there.

PS was the F3 bike Mr Tony? Mcmurdo?

If i could keep my wheels from floating away i would give you the weight of mine.
But i can tell you my caliper is bloody light and has special light weight pistons.