ESE's works engine tuner

[Zrt1200]

i looked at that facebook page some time ago but its a mess and plenty of the people havent a clue what theyre even talking about :laugh:


I see you noticed that as well. I only have a couple of post on Facebook. There is way to many (want to be's) there and like you said they dont have a clue. I probable dont either but I am willing to learn from the guys that do!!

[Zrt1200]

Hi Al, it's good to have you here, where we have all the facilities that we don't have on Farcebook, like proper chronology, and quote and search functions that really work :D.

Thanks Frits. I agree. The search here works as it should unlike in other places. I have taken many of screen shots already using the search feature here.

[husaberg]

NO!!! Sad to hear that. Your pictures are a real treasure and would be a great loss not to have here to go through.

Wish there was something we could do to have “someone in charge” change their mind...or something.
Totally understand your decision though...without knowing the background.


I don't know what is going on, but in any case save your treasures by uploading them to Google Drive. Then nothing is irrevocably lost, and you can decide who you want to give access to the material.


Husaberg fired?

what's this shit?

You express yourself correctly, participate in discussions.

Soon it's the topic that will disturb....


Husaberg is one of the most respected forummembers, I hope that whatever the source of dispute is, it will get sorted out.


Moderators, think about what you are doing, you will wreak this site, Glenn is a national treasure and should be treated as such, with some respect!


+1

Listen to the community in this case.


WTF did I miss , can I sign a " Bring Back Husa Petition "
Seriously , what went on ?


+1 .


Cant believe Husa, so much nice material. Is it happen today after you posted image of TZ 750 exhaust or earlier?
On image history browser pictures are still visible.


+15....:msn-wink:


He's fired ??????????????

That's total CRAP

We want Glenn, Husa or is it Hooser or, in fact, the whole three of them !!!!!!!!!!!!!!!!!!!.


:shit:

Ditto for Me


Where do I sign!!!


Hi Husaburg
I love your pictures and posts on here, I hope we don't loose you.
Warmest Regards TZ

Thanks for the support its most humbling, but i am afraid its a done deal, As i said, it's became obvious the people that run the site, value racist trolls that do not post anything MC related "feelings" , above people who are into bikes and post stuff onto the forums.
Thus we have arrived at a situation we have now. Where i are not going to be posting any more pics onto KB, and i intend in the near future i intend to remove all that i can for storage under my own control , (Which will have to wait until when the site owners deem it fit that i am again allowed access to my own files.) you have to love that, as now i cant even access the pictures i posted here now.
That's not to say i will be leaving the forum ,i just dont intend to be supporting it any longer with the thousands of picture's i had on the site. or visiting it so often.

TZ along with all those here that have posted information so freely has created what i would call the best resource on the internet for 2 stroke information.
I wish all those here well. i have met some wonderful people from here Neil Rob and Greg, the hillbillies.
Plus next time i go to WA i intend to drop on on Ken.

https://www.youtube.com/watch?v=mTFZJxU9pJ4

[wobbly]

So who " owns " this site , and has the power to block access to someones data without any reference to those that value, and have valuable input to this community.
Sounds like we need a Snowden whistleblower to expose those abusing their power over free intercourse on here.

[KKT]

Sure we can, KKT. Take a look here: https://drive.google.com/drive/folders/18l2ShH-MzrnTO0uEk9rNTk89_KgwgWof
(https://drive.google.com/drive/folders/18l2ShH-MzrnTO0uEk9rNTk89_KgwgWof)


Thank you very much Mr Overmars :)

[Carel H]

it's became obvious the people that run the site, value racist trolls that do not post anything MC related "feelings" , above people who are into bikes and post stuff onto the forums.


My respect for your standing up against racism, I did'nt see it as Buckets is a forum within a forum.

I will stop contributing.

[F5 Dave]

Ok some history as I see it.

KB was formed and presumably still owned by a chap called Ashley. A good egg for doing so all those years ago. The forum was very large in membership and breadth of participation. This has inevitably decreased with farcebook etc. Ashley always promoted very light moderation . But be clear it isnt a democracy. He could turn it off if he pleased.

He has stepped back and leaves others to moderate it.

As usual there are some FWs who visit the site and talk crap but the thing that makes free speech important also leaves it vulnerable.

In some of the other areas there are all sorts of discussions that turn into handbag fights.
Glen it has to be said wades into perhaps too many of them and you cant wrestle with troll and not get muddy. So he gets infractions from moderators. And I've got quite close to those same infractions myself when I've been silly enough to join in (several beers in).


But that is not even in this section or even this thread.
Please dont think this thread is somehow compromised by evil overlordship. This is a thread that is unique and the forum itself is a great place.

Glen my personal advice would be brush that off and decide not to go to the handbag area. I think I will try to follow my own advice.
But dont turn a tiff with the moderators into something it is not. You have been an asset of research. The only people who care about the content are the people here.

[TZ350]

343569 343570

Trying a new idea on Pinky. An electronic temperature sensor controller that turns the water pump on when required.
Seems to hold the temperature reasonable steady on the dyno. The real test will be in the 2 hour endurance race on Sunday.

[husaberg]

Ok some history as I see it.

KB was formed and presumably still owned by a chap called Ashley. A good egg for doing so all those years ago. The forum was very large in membership and breadth of participation. This has inevitably decreased with farcebook etc. Ashley always promoted very light moderation . But be clear it isnt a democracy. He could turn it off if he pleased.

He has stepped back and leaves others to moderate it.

As usual there are some FWs who visit the site and talk crap but the thing that makes free speech important also leaves it vulnerable.

In some of the other areas there are all sorts of discussions that turn into handbag fights.
Glen it has to be said wades into perhaps too many of them and you cant wrestle with troll and not get muddy. So he gets infractions from moderators. And I've got quite close to those same infractions myself when I've been silly enough to join in (several beers in).


But that is not even in this section or even this thread.
Please dont think this thread is somehow compromised by evil overlordship. This is a thread that is unique and the forum itself is a great place.

Glen my personal advice would be brush that off and decide not to go to the handbag area. I think I will try to follow my own advice.
But dont turn a tiff with the moderators into something it is not. You have been an asset of research. The only people who care about the content are the people here.

I appreciate what you are saying Dave, but it is not some tiff, nor have i received infractions resulting in me being sin binned, i have zero current infractions i have only ever received a few the whole how many it is i have been a member.
Spanks can do what he wishes with the site, as you said its never been a democracy, but it will not be with me having a whole heap of pics on it. Light moderation, heavy moderation, no moderation i dont care ,any which way, as long as it s consistent and transparent, which its clearly not
If the moderators want to support the trolls that are on the site (some of which are siblings of the moderators.) They can have the place as far as i am concerned.
I know quite a few on here who have been mods on this site they also have left they leave as they get sick of the same crap i have.

[SwePatrick]

There is already a bend in the header.
Put a bend at the end of the header/start of diffuser join , then one at the end of the diffuser/start of the mid section.
No extra cuts or welds - easy.
Oval changes the area and thus the pipes efficiency - bad idea.

The bend after the header will have a joint to be able to change diffusors etc etc.
After that bend it is simpliest that way to build a straight pipe.
And if bending the pipe to the side of the wheel i need to bend it early as the pipe is quite big at the belly, and by that i need to modify the frame and seating position to not burn the leg.
I haven´t made it oval yet, and i´m aware of it will loose effiency, but a slight oval like from 170mm diam to 160/180 i would say does almost nothing.

[speedpro]

but a slight oval like from 170mm diam to 160/180 i would say does almost nothing.

Calculate the cross sectional area of the 2 shapes - round and oval. I think what you will need to try and achieve is the same cross sectional area at the same distance from the piston in the oval cross section as in the round cross section. The other problem will be the flexibility of the walls caused by the pressure fluctuations inside the pipe. It probably won't be much, and probably will cause little problem in real life. The round pipe will of course 100% resist any deformation. The thinner the sheetmetal the worse it will be.

[ken seeber]

All I know is that I visit and contribute to ESE, Foundry and Oddball Engines, just as Husa does (plus more it seems). In all that time, since my joining in 2013, Husa has been nothing than a positive, generous and resourceful contributor.

This can been attested by the support he has received. I do take on Dave’s points and maybe Glen does get in too deep on occasions, but certainly not so where I go.

As to BuzzardNZ & now Katman, I can’t make many comments, other than I have never seen you on the threads I visit. Maybe Glen has fucked up elsewhere. As to being an arsehole, what can anyone say? We’ve all got one and, I’m sure, have all made mistakes when the arsehole side comes out and we have to learn not to.

Conclusion: We want Husa.

[DougW]

I discovered this thread about a year ago and have just got to the last post after starting from the beginning.
I had previously found some of Frits priceless posts on pitlane biz, but to be honest a lot of the info on there went over my head. (been riding and occasionally racing two strokes since 1978, old git)
Reading the thread from the beginning has helped me get my head around some of the intricacies of making a two stroke work better, and made some of the info I got from the late Terry Shepherd (RIP) and the Robinson book clearer.

So I just want to say a massive "THank YOU" to TZ350 for starting this thread and to everyone who has made a positive contribution to it.

[onearmedbandit]

I've pruned a lot of posts tonight that are off topic. Leave it out of this thread please.

[onearmedbandit]

More posts removed and infractions handed out.

To those that genuinely participate in this thread please do not respond to any off topic posts, rather just report them and I will take care of it.

[WilDun]

I haven't been here for quite some time and so have missed most of the story of what has happened with Husa, so I must admit that I'm still a little sketchy on what it's all about, but Husa has always been an asset here and elswhere!
I used to wade in too in the odd occasion - (not any more), but Husa is a really well known(and liked) guy on this forum, most of us understand him to be a good guy!

Sure, he goes a little overboard on the very odd occasion but what is wrong with that? - so do many others, (including me), but isn't he is the best chronicler? archivist? we've ever had ...... and he's been banned? - his pictures taken down by (apparently) "self righteous" reformers? ...... perhaps I'm wrong, I dunno.
He has much support from people who have contributed some truly good material to the thread - but this does not seem to deter those who have more of a passion for policing and applying rigid rules, than for actually modifying bikes or at least having interesting discussions and sharing of ideas on the subject! ........... Just understand the guy I say!

[onearmedbandit]

I haven't been here for quite some time and so have missed most of the story of what has happened with Husa, so I must admit that I'm still a little sketchy on what it's all about, but Husa has always been an asset here and elswhere!
I used to wade in too in the odd occasion - (not any more), but Husa is a really well known(and liked) guy on this forum, most of us understand him to be a good guy!

Sure, he goes a little overboard on the very odd occasion but what is wrong with that? - so do many others, (including me), but isn't he is the best chronicler? archivist? we've ever had ...... and he's been banned? - his pictures taken down by (apparently) "self righteous" reformers? ...... perhaps I'm wrong, I dunno.
He has much support from people who have contributed some truly good material to the thread - but this does not seem to deter those who have more of a passion for policing and applying rigid rules, than for actually modifying bikes or at least having interesting discussions and sharing of ideas on the subject! ........... Just understand the guy I say!

I was not involved in the action taken against husaberg (I believe this was done by the site owner himself) however I would like to clear a few things up.

Firstly, he is not banned, rather in the sinbin. This removes several privileges from the member in question.
His images have not been removed. They are still there to see. If he chooses to remove them that is his choice.
There is no collusion between any moderator and other members of the site (including family of moderators) that led to his sin binning.
There have been a number of ongoing issues in other areas of the site that have resulted in this action being taken. Unfortunately this affects their participation in all areas of the forum.

KB is not heavily moderated, but when things keep flaring up with regularity action will be taken. Very few 'genuine' contributors have ever been banned from the site. We don't always get it right but we do pretty damn well for people who have lives other than baby-sitting threads because certain members like to take things too far.

Please can we leave this thread for what it is intended for. If yoiu have anything you want to discuss regarding our actions PM a moderator or start a thread in the appropriate section. Any more posts off topic will be removed.

[Zrt1200]

I have run into a problem that requires some out of the box thinking. On this crankshaft the small end of the connecting rod ID is 27mm which is designed for a 22 X 27 X 23.8mm wrist pin bearing. The piston we want to use is a off the shelf Rotax piston with a 18mm wrist pin. The way I see it I will either need to sleeve the small end of the rod with a hardened needle bearing race. (Seems like a bad idea) Or use 4.5mm loose needle bearings. If my math is right 27mm - 18mm = 9mm / 2 = 4.5mm + 18mm = 22.5 X pie / 4.5 = 15.7 needles. So I would be installing 15, 4.5 X 23.8mm loose needle bearing rollers. What do you guys think??

[husaberg]

I have run into a problem that requires some out of the box thinking. On this crankshaft the small end of the connecting rod ID is 27mm which is designed for a 22 X 27 X 23.8mm wrist pin bearing. The piston we want to use is a off the shelf Rotax piston with a 18mm wrist pin. The way I see it I will either need to sleeve the small end of the rod with a hardened needle bearing race. (Seems like a bad idea) Or use 4.5mm loose needle bearings. If my math is right 27mm - 18mm = 9mm / 2 = 4.5mm + 18mm = 22.5 X pie / 4.5 = 15.7 needles. So I would be installing 15, 4.5 X 23.8mm loose needle bearing rollers. What do you guys think??

change the entire rod whats the conrod dimensions

[WilDun]

I was not involved in the action taken against husaberg (I believe this was done by the site owner himself) however I would like to clear a few things up..................

Please can we leave this thread for what it is intended for. If yoiu have anything you want to discuss regarding our actions PM a moderator or start a thread in the appropriate section. Any more posts off topic will be removed.

Understood - :niceone:

[peewee]

I have run into a problem that requires some out of the box thinking. On this crankshaft the small end of the connecting rod ID is 27mm which is designed for a 22 X 27 X 23.8mm wrist pin bearing. The piston we want to use is a off the shelf Rotax piston with a 18mm wrist pin. The way I see it I will either need to sleeve the small end of the rod with a hardened needle bearing race. (Seems like a bad idea) Or use 4.5mm loose needle bearings. If my math is right 27mm - 18mm = 9mm / 2 = 4.5mm + 18mm = 22.5 X pie / 4.5 = 15.7 needles. So I would be installing 15, 4.5 X 23.8mm loose needle bearing rollers. What do you guys think??

check the prox catalog for something. i mixed yami piston and ktm rod and i believe suzuki small bearing. made my own thrust washers to keep it centered

[Zrt1200]

check the prox catalog for something. i mixed yami piston and ktm rod and i believe suzuki small bearing. made my own thrust washers to keep it centered

I have checked ProX & Hotrods. I wanted to just change the rods out but in this case it would require shredding the crank, Welding up the crank holes. Bore and Jig grind or EDM the new holes to a smaller pin diameter. The rods on the crank now have a 26mm big pin and the rod length is 135mm. I would prefer to go to a longer rod but I have a over all height I must retain because of the rules for the class. My Build is a Arctic cat ZRT-800 engine. The stock stroke is 65mm. So Stock is a 72X65. I am building a 70X70 3 cylinder for drag racing. I dont have a problem with loose rollers. I am just not sure of the .7mm gap between all of them?? Is that to much or not enough??

[Muciek]

I have checked ProX & Hotrods. I wanted to just change the rods out but in this case it would require shredding the crank, Welding up the crank holes. Bore and Jig grind or EDM the new holes to a smaller pin diameter. The rods on the crank now have a 26mm big pin and the rod length is 135mm. I would prefer to go to a longer rod but I have a over all height I must retain because of the rules for the class. My Build is a Arctic cat ZRT-800 engine. The stock stroke is 65mm. So Stock is a 72X65. I am building a 70X70 3 cylinder for drag racing. I dont have a problem with loose rollers. I am just not sure of the .7mm gap between all of them?? Is that to much or not enough??


Hey, MZ TS250 ES250/0 ES250/1 ES250/2 had 135mm center to center rod with 18mm you can get them with nice silver cage bearing. Big end pins are 28mm but it's easy work to step them to 26 you need. Don't know what would be the availability in your country...

[ceci]

I know this topic is already old in this forum.
But seeing a gif image of the Ryger engine on facebook, what is the amount of cargo charged for its renewal.
He looked at the Ryger engine as contrary to the Dunelt

[jamathi]

I know this topic is already old in this forum.
But seeing a gif image of the Ryger engine on facebook, what is the amount of cargo charged for its renewal.
He looked at the Ryger engine as contrary to the Dunelt

It finally seems to be DEAD!
No surprise of course....
50 engines for the scrapheap, that has been waiting for years.
Nobody will be really sad.
Except the investors, but that is the price for being STUPID.....

[ceci]

I know this topic is already old in this forum.
But seeing a gif image of the Ryger engine on facebook, what is the amount of cargo charged for its renewal.
He looked at the Ryger engine as contrary to the Dunelt



The mystery to me is what is the actual displacement of the Ryger engine?

[ceci]

I'm wrong? . For me the actual displacement is 55 cc.
When ascending this piston that is the cubic volume that it creates in the lower part of it.
At the top of the piston, combustion chamber the volume if it is 125cchttps://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=317124&d=1446790730

[JanBros]

combustion takes place above the piston, so it's the displacement above the piston that count's.

[Michael Moore]

Hey, MZ TS250 ES250/0 ES250/1 ES250/2 had 135mm center to center rod with 18mm you can get them with nice silver cage bearing. Big end pins are 28mm but it's easy work to step them to 26 you need. Don't know what would be the availability in your country...

It looks like the MZ is a 130mm O.C. rod length

https://www.con-rods.com/for-mz-ts250-pa39.html
MZ TS250
Big-end Width (mm): 20
Small-end Width (mm): 20
Big-end Bore (mm): 35
Small-end Bore (mm): 22
Center-to-center (mm): 130
Pin Diameter (mm): 28
Pin Length (mm): 60
Big-end Bearing (mm): 28*35*20
Small-end Bearing (mm): 18*22*24
Washer Thickness (mm): 0.5

[wobbly]

Re the Ryger - Jan said no one will be really sad.
I am sad that so much effort was expended on ego stroking and media hyped up bullshit , and not the application of superior engineering skills.
Stupid the investors may in fact have been , but they had some super clever spin creators running the show.
You must admit , to actually convince them ( and yourself ) that 70 Hp and 30,000 rpm were even remotely possible takes a class one narcissistic character , or
a bare faced bullshit artist with no shame at all - tough call there I would say.
The chief spin creator even got angry with our unbelieving derision - to the point of being shoved in the naughty room with Husa and his mates.
If only all that energy had been spent on actually solving the technical issues ( one wonders why Frits bailed real quick ) , but maybe he saw the fatal flaws before anyone
under his restrictive NDA.
A sad indictment on shite over substance.

[F5 Dave]

So as I lay awake last night I pondered the multi cylinder engine with pipes tuned to different peak power as a curve extension method vs just using less aggressive cones on all 4. The lower peak would have to have some serious over rev though. This must happen, or be accounted for, to some extent with rear pipes lack of cooling.

[andreas]

So as I lay awake last night I pondered the multi cylinder engine with pipes tuned to different peak power as a curve extension method vs just using less aggressive cones on all 4. The lower peak would have to have some serious over rev though. This must happen, or be accounted for, to some extent with rear pipes lack of cooling.

Maybe a servo controlled wind tunnel system for back pipes, although the whole idea seem to work better as a lullaby.:)

[ceci]

combustion takes place above the piston, so it's the displacement above the piston that count's.


It's funny that it indicates as the most powerful of the 125 2S engines, when its design only allows half of its combustion chamber to be filled

[wobbly]

Yea , but you are ignoring pipe supercharging - the delivery ratio is well above unity, and the scavenging efficiency/trapping efficiency are thru the roof.

[wax]

Does any one have a source for low friction oil seals, I know you can buy ptfe seals but for the life of me I cant find some one who sells them

[Brett S]

Does any one have a source for low friction oil seals, I know you can buy ptfe seals but for the life of me I cant find some one who sells them

We have all common sizes for 100cc and 125cc karts in stock in perth, all japanese ptfe lipped.
Strike Products 08 9303 4915

[jato]

I have checked ProX & Hotrods. I wanted to just change the rods out but in this case it would require shredding the crank, Welding up the crank holes. Bore and Jig grind or EDM the new holes to a smaller pin diameter. The rods on the crank now have a 26mm big pin and the rod length is 135mm. I would prefer to go to a longer rod but I have a over all height I must retain because of the rules for the class. My Build is a Arctic cat ZRT-800 engine. The stock stroke is 65mm. So Stock is a 72X65. I am building a 70X70 3 cylinder for drag racing. I dont have a problem with loose rollers. I am just not sure of the .7mm gap between all of them?? Is that to much or not enough??

I reckon a .7mm gap would be ok but the gap will be .7 of a 4.5mm roller (3.15mm) and so those rollers are going to be constantly very slightly skidding/bunching up away from the load (a bit like modern day apprentices) and eventually there will be rod damage and failure - it might take a while though... no doubt you are planning on using steel thrust washers to stop them digging into the piston bosses. good luck.

[peewee]

the only place ive known to use cageless needles was in dirt bike swingarms and theyre coated with thick grease for lubrication. yes it seems like they would bunch up and skid in a conrod application. ive no experience with a hardened insert in the small end but it may work for a short run engine. other wise maybe custom make some suitable conrods. can a crankshaft from another engine be used ? ive bored the crankpin holes larger with sucess but ive never tried to make the hole smaller. not sure if they can still be found but ktm used to have 135mm conrods with 24mm lower pin and 18mm upper

[wolfie]

Mercury Marine 2 strokes used to use loose rollers in the little ends.

I did my apprenticeship on them in the 70's, great motors.

https://www.ebay.com/itm/1980-Mercury-50-HP-outboard-2-Connecting-Rods-and-Bearings-Wrist-Pins/143391068408?hash=item2162c610f8:g:D0UAAOSwoSldh4n Q

Dave

[Niels Abildgaard]

You must admit , to actually convince them ( and yourself ) that 70 Hp and 30,000 rpm were even remotely possible takes a class one narcissistic character , or a bare faced bullshit artist with no shame at all - tough call there I would say.

A sad indictment on shite over substance.




The HCCI process can do 500 rps (and does in 2.5ccm model aircraft engines) and that was how I read it.
Was it stated anywhere that the 125ccm had done 500 rps or was expected to?

[Flettner]

lot of talk on a KTM site about TPI, usual wankers that don't even own one or even ridden one or for that matter even know how TPI works, have it that KTM don't know what they are doing regarding oiling.
I am not allowd to post stuff thats not KTM on their thread but was asked by peter1962 about my oiling system. Here is a picture, crank spiggot fits into this small seal. Seal cover is off at the moment. Cover holds the seal in position and is where the autolube oil line bolts up to. Oil direct to the bigend. Autolube pump is crank driven, cable operation ( normaly off the twist grip) now is activated via the power valve.

[Niels Abildgaard]

I have checked ProX & Hotrods. I wanted to just change the rods out but in this case it would require shredding the crank, Welding up the crank holes. Bore and Jig grind or EDM the new holes to a smaller pin diameter. The rods on the crank now have a 26mm big pin and the rod length is 135mm. I would prefer to go to a longer rod but I have a over all height I must retain because of the rules for the class. My Build is a Arctic cat ZRT-800 engine. The stock stroke is 65mm. So Stock is a 72X65. I am building a 70X70 3 cylinder for drag racing. I dont have a problem with loose rollers. I am just not sure of the .7mm gap between all of them?? Is that to much or not enough??

Jawa has made many mopeds with loose rollers and I have a set and can measure if need be.

https://www.jawaparts.com/Connecting-rod-complete-JAWA-50-550-555-d510.htm

[TZ350]

313942

On my way home I saw this pile of junk put out for the rubbish collection. I recognized that the crank was from a two stroke and grabbed it.

313943313944

Center main reed valve and split big end bearing and deflector top piston. My guess is, its from an old 2T Mercury V6 outboard.

313941313940

There had been an old Lola fitted with a 6 cylinder 2T boat engine, well it went pretty good so it was Banned of course ......

Possibly the most unusual T294 to have competed is Pietro Raddi's car, HU81, which is powered by a 2-litre Mercury engine from a powerboat.


Early Mercury outboard engines had split rod and loose crowded rollers in the big and little end bearings.

[Frits Overmars]

... the small end of the connecting rod ID is 27mm... The piston we want to use is a off the shelf Rotax piston with a 18mm wrist pin. The way I see it I will either need to sleeve the small end of the rod with a hardened needle bearing race. (Seems like a bad idea) Or use 4.5mm loose needle bearings. If my math is right 27mm - 18mm = 9mm / 2 = 4.5mm + 18mm = 22.5 X pie / 4.5 = 15.7 needles. So I would be installing 15, 4.5 X 23.8mm loose needle bearing rollers. What do you guys think??If you insist on using both that con rod and that piston, I'd reluctantly go for a hardened sleeve. The other option, a cageless crowded needle small end bearing, has been used by Jan Thiel in his world championship-winning 50cc Bultaco racer, still the prettiest 50cc bike I've ever seen.
343580
In your case it is paramount that you take the slack out from between the needles, or they will skew, skid and overheat. It can be done with one smaller-diameter needle that fills the gap.
A needle with a diameter of 3,0838 mm would completely fill it, but you need to use a somewhat smaller diameter, because the filler needle must not be allowed to carry any weight, otherwise it would be wedged between its neighbours, jamming all needle rotation.

The clearance will also allow for lubricant between the needles that are all rubbing against each other with a relative surface speed of double their circumference velocity. Reducing this rubbing is the main reason for using caged bearings.
In a small end bearing, with its limited rotation speed and swaying angle, you may get away with a cageless bearing. But in a big end bearing,
with its additional orbiting g-force flinging the needles against each other, you might just as well bin the crankshaft right-away.

The red filler needle in my drawing below is kept in place by its blue neighbours. If its diameter were less than 2,63 mm, it could radially move in- and outward through the gap between the blue needles. A diameter of 2,8 mm should be about right for this layout.
343579

[Zrt1200]

I reckon a .7mm gap would be ok but the gap will be .7 of a 4.5mm roller (3.15mm) and so those rollers are going to be constantly very slightly skidding/bunching up away from the load (a bit like modern day apprentices) and eventually there will be rod damage and failure - it might take a while though... no doubt you are planning on using steel thrust washers to stop them digging into the piston bosses. good luck.

Thanks for all the replies. Yes the .7 gap is what concerns me as well. Yes I was planning on steel thrust washers on each side of the needles. I would just sleeve it but I am sure a press fit in the small end would result in a broken rod.

Yes KTM has the correct rod but its not a simple fix to install that rod. I need to weigh out the cost of just selling this crank and getting a new one built with the KTM rods on it VS plugging the current pin holes and going to the smaller big end pin with the KTM rods on it.

A have seen a lot of loose needle bearing rollers, Mostly in Outboards and Skidoo/Rotax snowmobile engines.

I have priced what it would cost to have pistons made up and for the price of 12 pistons (Minimum that they would do) I can have a new crankshaft built and use off the shelf parts.

This crank originally was to be used in a 1200cc ProMod class which they outlawed after I had the crank built so I figured I would use it in a different build.

[ceci]

With 76mm x 61mm and rod (from your previous pic, add, looks like 25mm smaller dia /46mm bigger dia), pumping volume reduction is just 30cc, so from 276cc to 246cc it would be minimal influence.
Its similar to Rotax 503 engine.


In the Ryger the pumping volume reduction is 58cc, 50%.
As in this other engine

https://www.youtube.com/watch?v=TB9PGPnSEtA

[AndreasL]

If you insist on using both that con rod and that piston, I'd reluctantly go for a hardened sleeve. The other option, a cageless crowded needle small end bearing has been used with success by a feller named Jan Thiel in his world championship-winning 50cc Bultaco racer (below, still the nicest 50cc bike I've ever seen).
343580

Very nice Frits.
Monocoque chassis.
Do you have any further information about the (frame)design or know where to look?
The shifter mechanism looks really interesting to.

[Zrt1200]

If you insist on using both that con rod and that piston, I'd reluctantly go for a hardened sleeve. The other option, a cageless crowded needle small end bearing, has been used by Jan Thiel in his world championship-winning 50cc Bultaco racer, still the prettiest 50cc bike I've ever seen.
343580
In your case it is paramount that you take the slack out from between the needles, or they will skew, skid and overheat. It can be done with one smaller-diameter needle that fills the gap.
A needle with a diameter of 3,0838 mm would completely fill it, but you need to use a somewhat smaller diameter, because the filler needle must not be allowed to carry any weight, otherwise it would be wedged between its neighbours, jamming all needle rotation.

The clearance will also allow for lubricant between the needles that are all rubbing against each other with a relative surface speed of double their circumference velocity. Reducing this rubbing is the main reason for using caged bearings.
In a small end bearing, with its limited rotation speed and swaying angle, you may get away with a cageless bearing. But in a big end bearing,
with its additional orbiting g-force flinging the needles against each other, you might just as well bin the crankshaft right-away.

The red filler needle in my drawing below is kept in place by its blue neighbours. If its diameter were less than 2,63 mm, it could radially move in- and outward through the gap between the blue needles. A diameter of 2,8 mm should be about right for this layout.
343579

Thank you Frits. For some reason I did not see your post yesterday. At this point I am still trying to decide on what I should do. I know what is the right thing to do is. Change rods or crankshafts but I hate selling a new crankshaft that has never been run. If I did decide to go with a hardened sleeve. How much Press fit do you think i could get away with?? I had another thought on this today. If I used a 18 X 22mm hardened sleeve and had a ring fit or very light press fit on the wrist pin then I could use the stock 22 X 27mm needle bearing.

[F5 Dave]

How much would you prefer a ventilated crankcase? And it puts you down pretty quick let me tell you.

The earth is big heavy object when someone throws it at you.

[speedpro]

I can confirm that

[TZ350]

343589

Well, we got Pinky to the Two Hour endurance race but Pinky refused to play nice and did not make it to the start line.
A bit much I suppose to expect an un tried bike finished the night before to behave perfectly. We need a few shake down meetings to get things right.


343588

So Blair Lambarth and Nathaniel Diprose rode the number two GP-NSR110 and finished in third place. The only two stroke in the race.

This bike is basically a bog standard re plated Honda NSR250 cylinder on a Suzuki GP100 bottom end with a de stroked crank for 110cc's.
No porting or serious tuning work what so ever and they were able to run at the front for two hours with the big, bad boy 4 strokes.

The nosiest 4S was measured at 102db, the Team ESE 2S 95db and the quietest 4S's were at 92db.

343591343592343590

[F5 Dave]

Where was that held Rob?

[mr bucketracer]

at tokaroa 2 hour

[F5 Dave]

Of course, there's the crazy hairpin. Ran over Pumba there. Fence looked familiar but couldn't place it.

[Frits Overmars]

343593
Trying to shake that transponder to pieces? We've seen so many malfunctioning transponders that we added a line in the rulebook:
The transponder must be positioned at least 300 mm away from all ignition components and must be mounted in a vertical position as much as possible (manufacturer's prescription). The transponder may not be mounted on unsprung parts such as the lower legs of the front forks.

[yatasaki]

I'm wrong again

[mr bucketracer]

343593
Trying to shake that transponder to pieces? We've seen so many malfunctioning transponders that we added a line in the rulebook:and up side down

[guyhockley]

The nosiest 4S was measured at 102db, the Team ESE 2S 95db and the quietest 4S's were at 92db.


I was talking to a bloke who has a son who races 2 stroke Motocross and he claimed that in the UK we've lost many more tracks to noise complaints since 4 strokes took over.

[Frits Overmars]

I was talking to a bloke who has a son who races 2 stroke Motocross and he claimed that in the UK we've lost many more tracks to noise complaints since 4 strokes took over.Same here. A screaming two-stroke may get on some people's nerves (not mine) but when it's round the corner, you don't hear it anymore.
But you can still hear four-stroke when it's three forests away.

[JanBros]

yep, probably the main reason for the decline of Belgium as a top nation in MX. think we're down to 4 permanent MX tracks in the entire country . if you can't ride/train, ...

[TZ350]

343593
Trying to shake that transponder to pieces?

and up side down

So it is, good spotting ...... our bad, again. :D

Yes, I was surprised that the Two stroke measured louder on the sound meter than some four strokes but sounded much quieter than all of them.

[jasonu]

343588
The only two stroke in the race.
]

That's fucking sad!!!

[speedpro]

I kind of agree but there are a couple of very cool 4-strokes that nearly make up for it.

[F5 Dave]

It's the sad fact of so little base stock to build bikes from
. The MB100 in your Avatar is from 1978. That's 41 years old.

But I still have some crankcases just in case.

[jbiplane]

In the Ryger the pumping volume reduction is 58cc, 50%.
As in this other engine
https://www.youtube.com/watch?v=TB9PGPnSEtA

I use a bit other design. 50hp classical piston engine clone of 503cc Rotax was modified. I got 64hp at 6700 rpm without any additional modifications. 72 bore 61 stroke. http://www.reaa.ru/yabbfiles/Attachments/CreizCopf.jpg

[Flettner]

this is running?
Significant

[ceci]

I use a bit other design. 50hp classical piston engine clone of 503cc Rotax was modified. I got 64hp at 6700 rpm without any additional modifications. 72 bore 61 stroke. http://www.reaa.ru/yabbfiles/Attachments/CreizCopf.jpg


Congratulations on your success
It is evident that in his design, the loss of pumping volume is less.
The increase in power, what mystery is it due to?

[wobbly]

Praise the Lord - we have someone posting on here something of significance in two stroke performance advancement.
Congratulations JB on the effort , and as the quoted improvement is totally believable I feel no need whatsoever to ask to see the dyno printout.
Now , if like some other Sin Binned member , JB had posted only an outside view and said it made 100Hp at 20,000 rpm some on here might end up getting nasty
after 2 years of asking , and waiting , and waiting.
Hell no, not me.

[Flettner]

I wonder, is piston friction that significant, in a normal engine? 14 HP worth.
Ill bet the bugger vibrated somewhat��.

[speedpro]

Quite possibly piston friction is significant given the documented evidence of increased horsepower when oil is added to the mixture

[jbiplane]

this is running?
Significant
Runned previous version. Had to remake on CNC with better precision. Finally want to rework again for longevility. Have clear vision how. My current dyno is limited to 35 hp, so I use propeller (moulinette) to estimate power and got only one HP point, not complete graph. Dont sure if stock muffler is optinal for this engine. This experimental engine made for customer who will going to order me 2-stroke star for amateur aircraft use.

For vibration. the masses connected to connecting rod together add 37 grammes compare piston. May be in next design I'll be able decrease this difference.


Congratulations on your success
It is evident that in his design, the loss of pumping volume is less.
The increase in power, what mystery is it due to?
Frankly speaking I observe power increase in natural test but cannot clearly understand reasons.

[TZ350]

In the Ryger the pumping volume reduction is 58cc, 50%.
As in this other engine

343607

https://www.youtube.com/watch?v=TB9PGPnSEtA


I use a bit other design. 50hp classical piston engine clone of 503cc Rotax was modified. I got 64hp at 6700 rpm without any additional modifications. 72 bore 61 stroke. 343606

Great to see these experimental engines.

[husaberg]

In the Ryger the pumping volume reduction is 58cc, 50%.
As in this other engine

https://www.youtube.com/watch?v=TB9PGPnSEtA

Pretty sure that is actually Katinas engine.............

[ceci]

Praise the Lord - we have someone posting on here something of significance in two stroke performance advancement.
Congratulations JB on the effort , and as the quoted improvement is totally believable I feel no need whatsoever to ask to see the dyno printout.


bore 72 stroke 60, the powers are from 25CV of gasgas pampera to 37CV of bultaco pursang (without exhaust valve and classic distribution). Your data is within this logic

[jbiplane]

bore 72 stroke 60, the powers are from 25CV of gasgas pampera to 37CV of bultaco pursang (without exhaust valve and classic distribution). Your data is within this logic
All experimental engines which I made were preordered by customers.
Now customer happy with initial results and will continue experiments by himself using my "creuzcopf kits" = piston + rod + spacer.
I will modify this kits making it cheaper and more reliable in each iteration. One day I hope to make more radical design.

https://www.youtube.com/watch?v=tccPMi29tvc
Here gas forces from one cylinder compensated by opposite one. This engine can be statically balanced to 0.

[katinas]

Pretty sure that is actually Katinas engine.............

Good to hear you Husa, after all.

Yes, this is very first version 129cc, with main (upper) piston 57mm and lower 38mm stroke 50.6mm, pumping capacity lowered from 129cc to 71,7cc, so 44.4% reduced. And maybe because of that, zero torque at mid range ( 3500 to 7000 rpm) on all three versions (with two different cylinders from Honda Ns and Cr and three different pistons). Good example where “compressors mode” is needed when engine is off the pipe range.
In this video main piston is seized, only after I decide to test with very small amount of oil in fuel 1 to 100 and too little clearance for 2618 alloy piston .
Good progress in upper range was with Cr 125 cylinder (with 58 mm main piston) at latest tests, but broken piston ring (simply because forget to adjust ring gap) destroy piston and this is where I end and so much left untested.

[katinas]

JB, good to see your progress, nice work and 32 hp at 6700 rpm from 250cc same like on Honda NSR 500 V2 1/2 at 6700 rpm (max 69 hp at 10250rpm)
Be careful at playing with the oil amount.

[JanBros]

would a pipe like this make any sense ? In my head it does ... :innocent:

would be for my MX moped with vario. once moving the rev's do not change much, but quite often we have to accelerate from an (almost) standstill. So I moved the steep cones forward to give more power when revving higher, but keep some suction/pushing back for the lower rev's to give the automatic clutch a less harder time and I can let it engage at a bit lower rev's which would make them last longer.

[wobbly]

Na , that rear cone setup makes WAY less power everywhere.Been there tried that.
Slippy pipe is the answer.

[andreas]

Everybody falls for the same idea, but what is the theory behind baffle cone profile? The wave bounces like a unity, and not by increments of the taper, I'm thinking.

[Frits Overmars]

would a pipe like this make any sense ? In my head it does ... would be for my MX moped with vario. once moving the rev's do not change much, but quite often we have to accelerate from an (almost) standstill. So I moved the steep cones forward to give more power when revving higher, but keep some suction/pushing back for the lower rev's to give the automatic clutch a less harder time and I can let it engage at a bit lower rev's which would make them last longer.
Na , that rear cone setup makes WAY less power everywhere. Been there tried that.Slippy pipe is the answer.I tried a two-stage reflector like that on a model airplane engine, where the power required by the propeller is proportional to the third power of its rpm, and the engine struggles to get through the torque dip before coming on the pipe. But I experienced the same as Wobbly: it's doesn't work.

343633 343632

[JanBros]

ok, tnx, saves me the trouble of making one.

[jbiplane]

JB, good to see your progress, nice work and 32 hp at 6700 rpm from 250cc same like on Honda NSR 500 V2 1/2 at 6700 rpm (max 69 hp at 10250rpm)
Be careful at playing with the oil amount.

I observe at the first prototype bottom brass liner wearing. In few hours +0.03 mm, seems brass was too soft or initial gap too big).
On photo second prototype dont tested yet. Internal brass surface fit better and covered by inclined groovies.

I have too small dyno, used pervert way = air brake or moulinette. Will think how make cheap dyno to better understand engine behaviour.
I saw few years ago cheap dino drawings for cart engines. Cannot find anymore. May me somebody already have DIY dyno experiense?
Hydro or edge current ???

[JanBros]

a question before I can finalize my complete excel on porting and release it

if for example upscaling an RSA125 to a 250 using standard MX bore/stroke of 66.4/72 , keeping the same STA numbers and BMEP as the RSA125, I get :

rpm max power 9840
rpm max torgue 9000
max BHP 82.6
Bd A.A 20913.1
Tr A.A 158727.2
effective Bd port area 1217.4
effective port area transfer 1911.1
with :
Main Exh timing 198.4
Aux Exh timing 190.7
Tr A timing 128.6
Tr B and C timing 130.6

Anyone that can confirm ? Frits, if it's not too much trouble, can you do a sim with your software ?

[wobbly]

Sadly I think there is a fatal flaw in your power logic.The bmep achieved by the RSA was at 13000 rpm.
There is no way you can achieve the same bmep at 9000 simply due to the intake and pipe wave amplitude being so much greater at the higher rpm level.
This is shown by the actual numbers achieved by Honda with the 500V - best result after a few years work , was the factory bikes at around 70Hp/250cc cylinder at around 10,000 rpm with 68 square bore / stroke.
Even that engine was fragile if reved to 10500 too often, as they were , with the usual results.

[Frits Overmars]

If for example upscaling an RSA125 to a 250 using standard MX bore/stroke of 66.4/72 , keeping the same STA numbers and BMEP as the RSA125,
I get rpm max power 9840 ; rpm max torgue 9000 ; max BHP 82,6 . Frits, if it's not too much trouble, can you do a sim with your software ?It's not a matter of trouble Jan, but of incomplete data. I'd have to assume that all the data that you did not specify above, are equal to the RSA-data, which is doubtful because even their bore/stroke-ratios are rather different. I also assume that your 250cc engine will have reed valve induction, which makes it unlikely that you will be able to equal the BMEP of the rotary-valve RSA engine. Jan Thiel's experiments at Derbi showed about 10% power deficit between the best reedvalve engine and the best rotary valve engine of that era.

Wobbly has a point as well with his Honda-data. But there is a bit of hope for you, as development has continued since that Honda-research,
with the DEA 250cc kart engine (below) as an example. It reliably produces 72 hp at the chain at about 10.000 rpm, with reed valve induction.
343639

[Niels Abildgaard]

DEA 250cc kart engine (below) as an example.
It reliably produces 72 hp at the chain at about 10.000 rpm, with reed valve induction.
343639

That picture is pure pornography.
Do You have more like it and where?

[Niels Abildgaard]

a question before I can finalize my complete excel on porting and release it

if for example upscaling an RSA125 to a 250 using standard MX bore/stroke of 66.4/72 , keeping the same STA numbers and BMEP as the RSA125, I get :

rpm max power 9840
rpm max torgue 9000
max BHP 82.6
Bd A.A 20913.1
Tr A.A 158727.2
effective Bd port area 1217.4
effective port area transfer 1911.1
with :
Main Exh timing 198.4
Aux Exh timing 190.7
Tr A timing 128.6
Tr B and C timing 130.6

Anyone that can confirm ? Frits, if it's not too much trouble, can you do a sim with your software ?

Remarkably good numerical simulation I would say.
The DEA Frits points to is 72Hp.If Jan Thiels 10% more from rotary valves is valid it becomes 79 and Wobblys diminishing wave action takes three away.
You are spot on.
If two cylinder 50ccm was allowed by same logic they would be around 29Hp and sound funny

[Frits Overmars]

That picture is pure pornography. Do You have more like it and where?Yep, here you go Niels: https://drive.google.com/drive/folders/18l2ShH-MzrnTO0uEk9rNTk89_KgwgWof
That Google Drive is loaded with stripped racing engines and other two-stroke porn.

By the way, apart from its reed valve induction, that 250cc DEA engine really is a scaled-up version of the Aprilia RSA125.
No wonder, as DEA also builds the 250cc Superkart twin engine with rotary inlets, whose cylinders initially were carbon-copies of the RSA.
Later DEA applied some porting modifications in order to improve the power band of his kart engine, which was not allowed to use the electronically controlled powervalve and powerjet that helped the RSA to its broad spread of power.

[TerraRoot]

that's great news jbiplane, really happy someone went and did it and tested it!

perhaps you could run a simple test to see if the gains are coming from having less friction, run it up to speed cut ignition and time how long it takes to stop? compared to unmodified engine if that's available.

[JanBros]

Remarkably good numerical simulation I would say.


tnx, and that is all it was supposed to be. a theoretical test just to check if what I've created works and is correct. I have no plan's to built such an engine.
think of it that if I actualy had the resources to built an as correct as possible upscaled replica of the RSA but with a 66.4/72 bore/stroke, with everything else +/- the same.
rotary disk
using Frits' radial scavenging angles for the different bore/stroke
using the same swept compression ratio
etc
only changing bore/stroke and dropping rev's because of that.

and should have mentioned : 82.6 BHP at the crank, so that would be about 76-77 at the gearbox.

[JanBros]

It's not a matter of trouble Jan, but of incomplete data. I'd have to assume that all the data that you did not specify above, are equal to the RSA-data, which is doubtful because even their bore/stroke-ratios are rather different. I also assume that your 250cc engine will have reed valve induction, which makes it unlikely that you will be able to equal the BMEP of the rotary-valve RSA engine. Jan Thiel's experiments at Derbi showed about 10% power deficit between the best reedvalve engine and the best rotary valve engine of that era.

Wobbly has a point as well with his Honda-data. But there is a bit of hope for you, as development has continued since that Honda-research,
with the DEA 250cc kart engine (below) as an example. It reliably produces 72 hp at the chain at about 10.000 rpm, with reed valve induction.


as you can read in my post above : you may assume all of that. it's was purely theoretical based on STA numbers and just changing bore/stroke, drop rev's with minor tweaks. I had too much blowdown so I dropped the timings a bit.

the DEA shows at least my RPM and HP numbers are in the right ball-park, but those were the "easy" part of my example. finding out if the A.A numbers and port area numbers are correct is almost impossible unless someone with a known good programe does a sim to compare.

think of it this way : if mine are correct, you never ever have to do it again as you can point them in the future to my excel as I will be throwing it on the net free for anyone to do with it whatever they like :)

[Niels Abildgaard]

Yep, here you go Niels: https://drive.google.com/drive/folders/18l2ShH-MzrnTO0uEk9rNTk89_KgwgWof
That Google Drive is loaded with stripped racing engines and other two-stroke porn.

By the way, apart from its reed valve induction, that 250cc DEA engine really is a scaled-up version of the Aprilia RSA125.
No wonder, as DEA also builds the 250cc Superkart twin engine with rotary inlets, which initially was a carbon-copy of the RSA.
Later DEA applied some porting modifications in order to improve the power band of his kart engine, which was not allowed to use the electronically controlled powervalve and powerjet that helped the RSA to its broad spread of power.

Thank You for pictures.It is raining and I need something to look at.
The PVP Karts in Denmark was also inspired by the RSA cylinders and make plus 100 Hp from two of those in tandem.
I tried to interest him in my faboluos V2 with unified crankcase volume and he was not the least interested.
Clever guy with sound reactions.

[Frits Overmars]

changing bore/stroke... I had too much blowdown so I dropped the timings a bit.That's the nice thing with a long-stroke engine.


...finding out if the A.A numbers and port area numbers are correct is almost impossible unless someone with a known good programe does a sim to compare... if mine are correct, you never ever have to do it again as you can point them in the future to my excel as I will be throwing it on the net free for anyone to do with it whatever they likeThat's the spirit, Jan :niceone:.


I tried to interest him in my faboluos V2 with unified crankcase volume and he was not the least interested. Clever guy with sound reactions.:D

[lohring]

I observe at the first prototype bottom brass liner wearing. In few hours +0.03 mm, seems brass was too soft or initial gap too big).
On photo second prototype dont tested yet. Internal brass surface fit better and covered by inclined groovies.

I have too small dyno, used pervert way = air brake or moulinette. Will think how make cheap dyno to better understand engine behaviour.
I saw few years ago cheap dino drawings for cart engines. Cannot find anymore. May me somebody already have DIY dyno experiense?
Hydro or edge current ???

I've a lot of experience with a DIY inertial dyno for testing small (26 to 35 cc) engines. A summary of that and other's experiences is at namba.com/content/library/propwash/2019/april/16/ You probably need a bigger, geared duno. My favorite article on that is at http://performancetrends.com/tdkmotorsports/index.html

Lohring Miller

[jbiplane]

that's great news jbiplane, really happy someone went and did it and tested it!
perhaps you could run a simple test to see if the gains are coming from having less friction, run it up to speed cut ignition and time how long it takes to stop? compared to unmodified engine if that's available.

I did numerous errors in design, have to completelly rework for acceptable longevity. Hope in the next iteration will be essential progress.


A summary of that and other's experiences is at namba.com/content/library/propwash/2019/april/16/ You probably need a bigger, geared duno. My favorite article on that is at http://performancetrends.com/tdkmotorsports/index.html
Lohring Miller
Thanks, will carefully read


my faboluos V2 with unified crankcase volume and he was not the least interested.
Where to read about?

[katinas]

I observe at the first prototype bottom brass liner wearing. In few hours +0.03 mm, seems brass was too soft or initial gap too big).
On photo second prototype dont tested yet. Internal brass surface fit better and covered by inclined groovies.



172 Beryllium copper would be good choice, hardness is similar to steel.
https://www.alro.com/divsteel/metals_gridpt.aspx?gp=0169&gpn=172%20Beryllium%20Copper&Mat=copper&Type=plate
https://www.ebay.co.uk/itm/Facom-440-3-4-Sr-3-4-AF-Non-Sparking-Combi-Spanner-Anti-Magnetic-Cu-Be-Alloy-/223589719243

Tested CuAl10Fe3Mn2 / CW306G for cylinder liner, wears little quicker than iron, but thermal conductivity incomparable.

[speedpro]

I had a Berrylium copper toolkit for working on the cross field amplifier(CFA) in the radar when I was in the air Force. The CFA had very strong magnets. We were told if we damaged a tool to leave immediately, close the room behind us and report it. Not good stuff apparently.

[Niels Abildgaard]

Where to read about?

Here:
https://www.homebuiltairplanes.com/forums/threads/side-valved-two-strokes-for-angels.32119/

[Niels Abildgaard]

I had a Berrylium copper toolkit for working on the cross field amplifier(CFA) in the radar when I was in the air Force. The CFA had very strong magnets. We were told if we damaged a tool to leave immediately, close the room behind us and report it. Not good stuff apparently.

Beryliumoxide is extremely poisoneous.

[husaberg]

Beryliumoxide is extremely poisoneous.

Pretty sure that's why its banned for most Motorsports despite its many advantages.

[ceci]

I tried to interest him in my faboluos V2 with unified crankcase volume and he was not the least interested.
.

This concept is more suitable for single cylinder supercharging (DKW).
The filling of the cylinders is done equally?
https://www.homebuiltairplanes.com/forums/media/crosssection.79560/full?lightbox=1&update=1566919607

[jbiplane]

...
Tested CuAl10Fe3Mn2 / CW306G for cylinder liner, wears little quicker than iron, but thermal conductivity incomparable.
Good idea, I will estimate if it will work as liner for wankel engine. I want to make and test 218cc next year.

[lohring]

Model engines have run chromed brass or aluminum liners for years. Their expansion matches high silicon aluminum pistons. The 35 cc engine we developed had a chromed brass liner with a ringed piston. See https://modelgasboats.com/magazine/tech-articles-mainmenu-608/244-cmb-35-record-engine

Lohring Miller

[Niels Abildgaard]

[QUOTE=ceci;1131145613]
The filling of the cylinders is done equally?

That was what I asked the PVP owner about.
It could easily be tested by using an not up to date anymore engine and then phase one crank 90 degree to the other,cross connect the carburators and let us try.My theory is that at high power crankcase/piston underside pumping means nothing and exhaust pipes everything.

https://www.pvpkart.com/104%20PVP%20Motor%20right.jpg

[Frits Overmars]

My theory is that at high power crankcase/piston underside pumping means nothing and exhaust pipes everything.I agree so far, Niels. But then what happens?
The exhaust pipe that is the first to come, sucks up everything it can get, thereby reducing the crankcase pressure. The second exhaust pipe can then suck up less mixture and the combustion in the second cylinder will produce exhaust gas with less energy. In the next cycle, the second exhaust pipe, with less energy to work with, will therefore suck up even less mixture. And so on...

This phenomenon even occurs in two-stroke boxer engines in which both exhaust pipes simultaneously suck from a common crankcase.
In theory this should not cause inequality, but in practice, even the smallest initial deviation leads to one of the cylinders performing worse and worse. Therefore, even in a boxer engine, it is advisable to provide the crankshaft center disk with a circumferential groove and a stationary 'piston ring' that separates both sides of the crankcase.

[Niels Abildgaard]

I agree so far, Niels. But then what happens?
The exhaust pipe that is the first to come, sucks up everything it can get, thereby reducing the crankcase pressure. The second exhaust pipe can then suck up less mixture and the combustion in the second cylinder will produce exhaust gas with less energy. In the next cycle, the second exhaust pipe, with less energy to work with, will therefore suck up even less mixture. And so on...

This phenomenon even occurs in two-stroke boxer engines in which both exhaust pipes simultaneously suck from a common crankcase.
In theory this should not cause inequality, but in practice, even the smallest initial deviation leads to one of the cylinders performing worse and worse. Therefore, even in a boxer engine, it is advisable to provide the crankshaft center disk with a circumferential groove and a stationary 'piston ring' that separates both sides of the crankcase.

Thank You for explaining why show will stop in racing engines.
In aircraft with a Turbo it is still to early to drop it and long uncooled exhaust pipes is not really wellcome anyway

[ceci]

This phenomenon even occurs in two-stroke boxer engines in which both exhaust pipes simultaneously suck from a common crankcase.
In theory this should not cause inequality, but in practice, even the smallest initial deviation leads to one of the cylinders performing worse and worse. Therefore, even in a boxer engine, it is advisable to provide the crankshaft center disk with a circumferential groove and a stationary 'piston ring' that separates both sides of the crankcase.



What happens?, one cylinder is supercharged and the other is canceled.
The result is how this engine? , it is not boxer, its design is similar

[F5 Dave]

I can see some problems with that engine straight away. The lubrication is going to be parsimonious at best, and the compression ratio will struggle to get over atmospheric.

[Frits Overmars]

What happens? One cylinder is supercharged and the other is canceled. The result is how this engine? it is not boxer, its design is similarCeci, it may look like a boxer, and the crankshaft balance approaches that of a boxer, but the engine in your picture, a 50cc Motobécane 99Z from 1978, is a single-cylinder engine with a crankcase-pumping opposed piston, like the pre-war DKW racers.
So it has one exhaust pipe and zero problems with one firing cylinder starving the other, because there is no other.

[ceci]

The exhaust pipe that is the first to come, sucks up everything it can get, thereby reducing the crankcase pressure. The second exhaust pipe can then suck up less mixture and the combustion in the second cylinder will produce exhaust gas with less energy. In the next cycle, the second exhaust pipe, with less energy to work with, will therefore suck up even less mixture. And so on...

.

It can be said that the first cylinder is supercharged, it feeds more than it should, because it takes away from the other

[guyhockley]

Snip...
This phenomenon even occurs in two-stroke boxer engines in which both exhaust pipes simultaneously suck from a common crankcase.
Snip...

There was recently a brief discussion on Michael Moore's Chassis list about Konig engines. I realise the Siamese pipes were probably for packaging reasons, but I always wondered if linking simultaneous firing cylinders together might not have been better than the way they did it.
Pretty much like Kevin Cameron did on the TZ750.
Dick De Jager managed to squeeze 4 separate pipes into his KonigYam, anyway.

[Frits Overmars]

...I realise the Siamese pipes were probably for packaging reasons, but I always wondered if linking simultaneous firing cylinders together might not have been better...Yes, it would have.
Coupling the exhaust ducts from two cylinders that fire at 180° intervals can be very interesting if the exhaust timing is well over 200°. Then the exhaust opening pulse from cylinder A can shove the washed-through mixture from cylinder B back just before exhaust port B closes. And that primary pulse from cylinder A can easily be three times as strong as what a reflected pulse from a conventional expansion pipe could manage. That's some supercharging...

In the König layout the exhaust opening pulse from cylinder A arrives too late at cylinder B, when exhaust port B has already been closed, so the Y-connection from both cylinders to the single pipe has no useful function. On the contrary: when the exhaust system is doing its thing for cylinder A, the duct from the Y-piece to cylinder B is just a dead-ended side branch that dampens the exhaust resonance, like the ATAC volume on early Hondas. In the Hondas this was used to lessen the disturbance of exhaust pulses returning at the cylinder at the wrong time, below the power band. As soon as the engine ran in the power band, the ATAC volume was closed. But in a König that volume stays always open; no wonder its power left something to be desired.

[wobbly]

And adding to the effect of having very high exhaust duration you can cut the skirts short such that the port is open a few mm when the piston is at TDC.
Wreaks havoc with the jetting , but in the project i tried that we were using big pumper carbs.
Very easy to adjust the fuel curve as was needed - but I doubt a normal carb could be made to work.
This setup on a " stock " 950 SeaDoo gave an added 8 Hp in about 80 , so 10% - enough for the title at Havasu.
On a 1180 twin race motor the bump was 15 Hp in 120 so a little less.

[flyincat]

Thanks, Frits and Wobbly! I've always been interested in the 2 into 1 y-pipe and piston skirt discussions. Both on the same page is fantastic.

Frits, do you have any pictures of a y pipe that uses very high duration exhaust to supercharge the other cylinder? It seems the y pipe would have to have the shortest path possible between exhaust ports to limit how far above 200 deg the ex timing needs to be? Also, does the pipe need to be designed to scavange more than normal so there is extra fresh mixture in the y pipe to shove back in the cylinder?

Wobbly, I looked at the suction at the ex port piston face during tdc in engmod. It's there. Too bad there is no way to actually simulate the cut skirt! Is cutting the skirt something that would be more manageable on an EFI, especially direct'ish injected like Flettner or TZ350? Would this method especially benefit an intake restricted engine?

Thanks again.

[jbiplane]

Yes, it would have.
Coupling the exhaust ducts from two cylinders that fire at 180° intervals can be very interesting if

Is there any good to make common resonator for V90 2-cylinder engine with separate crank volumes?

[wobbly]

Flyncat , yes to both questions.

[Niels Abildgaard]

And adding to the effect of having very high exhaust duration you can cut the skirts short such that the port is open a few mm when the piston is at TDC.
Wreaks havoc with the jetting , but in the project i tried that we were using big pumper carbs.
Very easy to adjust the fuel curve as was needed - but I doubt a normal carb could be made to work.
This setup on a " stock " 950 SeaDoo gave an added 8 Hp in about 80 , so 10% - enough for the title at Havasu.
On a 1180 twin race motor the bump was 15 Hp in 120 so a little less.

McCullough drone engines had no exhust pipes whatsoever

https://www.wy2.org/engines/engines-various.php#mcculloch

I have had one once and think it had around 10mm clearance when piston were at tdc

[Frits Overmars]

Frits, do you have any pictures of a y pipe that uses very high duration exhaust to supercharge the other cylinder? It seems the y pipe would have to have the shortest path possible between exhaust ports to limit how far above 200 deg the ex timing needs to be? Also, does the pipe need to be designed to scavange more than normal so there is extra fresh mixture in the y pipe to shove back in the cylinder?Couldn't find any decent pictures. But you're correct on both accounts. The longer the path from cylinder A to cylinder B via the Y-junction is, the longer it takes for the primary pulse out of cylinder A to reach cylinder B, and the higher the exhaust timing needs to be in order to keep exhaust B open until all the fresh mixture has been pushed back into cylinder B.
But you can make the path from A to B too short, for example when you rotate the cylinders towards each other, so the exhaust ports are directly breathing into each others faces. Then the Y-junction, or what there is left of it, is so short that it cannot contain enough fresh mixture. And it's no use having a really strong pulse pushing back mixture that isn't there.

[Frits Overmars]

Is there any good to make common resonator for V90 2-cylinder engine with separate crank volumes?You could have a twin with a 90° included angle between the cylinders and a firing order of 180°, and then you could use the above-mentioned advantage of a Y-junction combined with high exhaust ports. In fact you might be able to shape that Y-junction even better than in a parallel-twin.
How you balance a 90° V-twin with a 180° firing order, is another matter....

[ceci]

And adding to the effect of having very high exhaust duration you can cut the skirts short such that the port is open a few mm when the piston is at TDC.
Wreaks havoc with the jetting , but in the project i tried that we were using big pumper carbs.
Very easy to adjust the fuel curve as was needed - but I doubt a normal carb could be made to work.
This setup on a " stock " 950 SeaDoo gave an added 8 Hp in about 80 , so 10% - enough for the title at Havasu.
On a 1180 twin race motor the bump was 15 Hp in 120 so a little less.

That fact intrigues me, filling (supercharging) supplement volume charge for the exhaust why it happens.
How to get that little supplement volume of cargo to the exhaust:
The depression of the main exhaust creates a venturi effect and attracts it
the inertia of the incoming mixture forces it out through this small slot.
Which of the two causes can it be?

[andreas]

That fact intrigues me, filling (supercharging) supplement volume charge for the exhaust why it happens.
How to get that little supplement volume of cargo to the exhaust:
The depression of the main exhaust creates a venturi effect and attracts it
the inertia of the incoming mixture forces it out through this small slot.
Which of the two causes can it be?

I believe it's the split suction wave from the single diffuser that find it's way into the tdc side crank case. Or it's explained on previous pages.

[ceci]

wobbly, your project excites me, it resembles the project that I would like to carry out. The two projects are based on supercharging the engine by providing an extra supplement through the exhaust.
In the project I want to carry out, being a single cylinder, the supplement is provided by an auxiliary pump cylinder
Attempts to find a suitable solution to provide that supplement

[ceci]

Another attempt, is based on the FOX cylinder of Mr. Frits Overmars

[JanBros]

My spreadsheet for porting, head and pipe is ready (well, for now, as such things are never "final" :argh:)

http://users.telenet.be/jannemie/JanBros%20%202-stroke%201.0.jpg
excel : http://users.telenet.be/jannemie/JanBros%202-stroke%201.0.xlsm
manual : http://users.telenet.be/jannemie/JanBros%20%202-stroke%201.0.docx

I've opened a seperate topic where we can discuss it if people feel the need.

https://www.kiwibiker.co.nz/forums/showthread.php/187285-2-stroke-excel-for-ports-heads-and-pipes?p=1131145957#post1131145957

[Frits Overmars]

My spreadsheet for porting, head and pipe is ready (well, for now, as such things are never "final" )
excel : http://users.telenet.be/jannemie/JanBros%202-stroke%201.0.xlsm
manual : http://users.telenet.be/jannemie/JanBros%20%202-stroke%201.0.docx
I've opened a seperate topic where we can discuss it if people feel the need.
https://www.kiwibiker.co.nz/forums/showthread.php/187285-2-stroke-excel-for-ports-heads-and-pipes?p=1131145957#post1131145957Bravo Jan :clap:! I know that it has been a tremendous amount of work.
I noticed that you refer to my 'Leaning Tower of Pisa' story. If you wish, you can download the complete Pisa-story from https://drive.google.com/drive/folders/18l2ShH-MzrnTO0uEk9rNTk89_KgwgWof , from the folder 'FOS Tips & Concepts', and bundle it with your masterpiece.
In fact, you can use everything you find there and use it, provided credits are respected.
You might also take a look at the disclaimer accompanying the 'FOS Exhaust Concept'; it is a bit more extensive than the older version that you quoted.
:niceone:

[Frits Overmars]

Frits, don't know if I have to congratulate you or ask you, looking at this graph :
is from my excel, entered all the RSA data (cylinder and head, and than calculated your FOS pipe. Red is standard FOS as by your fomula's with 57.5 BHP at crank and an exhaust temp of 587° to get the same length as the tubo102....Jan, I was so delighted with your praise that I did not notice until now, that the above value of 587 must have been the speed of sound instead of the exhaust gas temp. I already corrected this wherever I could and if you do the same, I can delete this post and pretend it never happened :rolleyes:

[JanBros]

changed it Frits :msn-wink:.

Guess it's an old habit of all the other pipe program's out there, and the old one I used; they all use exhaust gas temp as the changeable variable.

so checked my manual end excel and made the same mistake there :Oops:

so changed it and uploaded correct versions. Also put a direct link to the Pisa story in it if that's ok. I haven't got much upload space, and uploadeing the same again is a bit silly I think.

[marsheng]

Jan, I was so delighted with your praise that I did not notice until now, that the above value of 587 must have been the speed of sound instead of the exhaust gas temp.

Is it not always at the speed of sound? The speed just needs to be corrected for air temperature and pressure.

[cotswold]

The KTM went back on the dyno today, last time we were a little underwhelmed with 38 bhp and an awful curve.
John splashed out on a new FMF fatty and it added about 3 1/2 but the golden touch was winding the power valve spring right out flush,😜 it went from 41 ish up to 48, the curve was much stronger too, we’ll gear it to run where it’s strong and not use the overrev.
TZee made the magic happen as he was wondering how the Valve was adjusted, someone had wound the springs all the way in, I reverse engineered that and wound it all the way out and bingo an extra 8 BHP. :headbang:]
Green the original pipe, blue the new pipe, red the power valve wound out with the new pipe

[Frits Overmars]

Changed it Frits. Guess it's an old habit of all the other pipe program's out there, and the old one I used; they all use exhaust gas temp as the changeable variable.
I also put a direct link to the Pisa story in it if that's ok. I haven't got much upload space, and uploadeing the same again is a bit silly I think.It's fine by me Jan, but the link https://drive.google.com/drive/folders/1JXzzjE_Ol6LGs-yEMuy2DbpjdH-2R0f (https://drive.google.com/drive/folders/1JXzzjE_Ol6LGs-yEMuy2DbpjdH-2R0fs%20%20)
that I found in the updated version of your documentation, doesn't seem to work here...


Is it not always at the speed of sound? The speed just needs to be corrected for air temperature and pressure.Yes Marsheng, it's always the speed of sound. And if you want to work it out via the exhaust gas temperature (not the air temperature), you would have to know that temperature and you would have to know how to do the math. But why complicate a simple exhaust concept like mine?
Just enter the speed of sound directly and you're good. KISS, remember?

[andreas]

Here is the conversion between speed and temp: The front of all pressure waves travels at the local speed of sound, ao,

ao = ^YR(Texc + 273) m/s
R and Y be estimated to be as for air at atmospheric conditions, i.e., 287 J/kgK and 1.4,
respectively.

The roof is square root.
Blair

[Niels Abildgaard]

Here is the conversion between speed and temp: The front of all pressure waves travels at the local speed of sound, ao,

ao = ^YR(Texc + 273) m/s
R and Y be estimated to be as for air at atmospheric conditions, i.e., 287 J/kgK and 1.4,
respectively.

The roof is square root.
Blair

It can maybe be easier to remember this way:
Ad degree celcius of exhaust to 273.
Take the square root of this number and multiply by 20 and this is then speed of sound in meter per second.

Example

500 degree Celcius

500 +273 is equal to 773 and square root of 773 is27.8.
if 27.8 is multiplied by 20 we gett 556 meter per second

[JanBros]

It's fine by me Jan, but the link https://drive.google.com/drive/folders/1JXzzjE_Ol6LGs-yEMuy2DbpjdH-2R0f (https://drive.google.com/drive/folders/1JXzzjE_Ol6LGs-yEMuy2DbpjdH-2R0fs%20%20)
that I found in the updated version of your documentation, doesn't seem to work here...


direct link seems to be impossible, so removed the "hyperlink" from the word document.
pasting the link into a browser leeds the user to the FOS concepts folder and than they'll find it "somwhere in the middle" ;-)

[lodgernz]

It can maybe be easier to remember this way:
Ad degree celcius of exhaust to 273.
Take the square root of this number and multiply by 20 and this is then speed of sound in meter per second.

Example

500 degree Celcius

500 +273 is equal to 773 and square root of 773 is27.8.
if 27.8 is multiplied by 20 we gett 556 meter per second

This formula and the other one given above are only approximations for low temperatures around room temp and will be grossly inaccurate at exhaust temps.

The correct formula for Speed of Sound S at temperature T in ⁰C is:

S = 331.3*SQRT((T+273.15)/273.15) m/s

[TZ350]

343694

Started work on my Post Classic pre 72 Kawasaki F81M 250cc single racer.

Kawasaki rotary valve cases, Suzuki crank and air cooled cylinder, Honda CR250 rod kit. Enormous case volume and with a modern pipe and some Methanol in the mix to keep the engine temperatures down I am looking for 45 rear wheel hp @ 9,500 rpm. Fingers crossed.

[TZ350]

The KTM went back on the dyno today, last time we were a little underwhelmed with 38 bhp and an awful curve.....but the golden touch was winding the power valve spring right out flush,�� it went from 41 ish up to 48, the curve was much stronger too.
343697

Real interesting that KTM use the power valve to tame the power delivery so a new rider does not frighten themselves.

By winding the screw in and delaying the PV opening. You can dial the power down to suit the conditions. Makes sense using the PV like that.

[Frits Overmars]

direct link seems to be impossible, so removed the "hyperlink" from the word document.
pasting the link https://drive.google.com/drive/folders/1JXzzjE_Ol6LGs-yEMuy2DbpjdH-2R0fs
into a browser leeds the user to the FOS concepts folder and than they'll find it "somwhere in the middle"'Somewhere in the middle' is rather accurate but I think I can give an even better indication: look under the letter P for Pisa :msn-wink:.
How did you come up with this link Jan? I wouldn't know how to create it.

[Niels Abildgaard]

This formula and the other one given above are only approximations for low temperatures around room temp and will be grossly inaccurate at exhaust temps.

The correct formula for Speed of Sound S at temperature T in ⁰C is:

S = 331.3*SQRT((T+273.15)/273.15) m/s

This formula gives 557.38 meter per second and the twenty times square root thing gives 556.12 for 500 degree celcius.
Grossly inacurate or are You joking?

[lodgernz]

This formula gives 557.38 meter per second and the twenty times square root thing gives 556.12 for 500 degree celcius.
Grossly inacurate or are You joking?

I stand corrected.

S = 331.3 * SQRT((T+273.15) / 273.15) = 331.3 * SQRT(T+273.15) / SQRT(273.15)

= SQRT(273.15) = 16.53 and 331.3/16.53 = 20.04

so S = 20.04*SQRT(T+273.15)

as you correctly stated.

[JanBros]

'Somewhere in the middle' is rather accurate but I think I can give an even better indication: look under the letter P for Pisa :msn-wink:.
How did you come up with this link Jan? I wouldn't know how to create it.

it's just the adress in the adress-bar Frits, once you are in the FOS-folder. even you should have found that one : KISS'er than that is impossible :msn-wink:
but it didn't work as a "hyperlink" in a word document (holding ctrl while clicking it normaly opens links), so that's why you have to copy it and paste it directly in the adress-bar.

since you read my manual "deeply" to find the link, I didn't say too much stupid stuff in it did I ?

[husaberg]

Will these do?


Frits someone ofn KB was talking about the russian nuclear ramjet cruise missle that the russians have just admited blew up and killed a heap of Russian scientists a few months ago.
From a physics point of view what would a ramjet capable of mach 6 sound like
I have a suspicions its like a very loud 2t 3 cylinder chainsaw.
A V1 running at 5-8 times the speed?

The Russians are acting like its some new tech but the yanks had them running in the 60's.
Seriously though who thinks an air cooled Nuclear reactor without any concete casing is a good idea. :)

[Frits Overmars]

How did you come up with this link Jan? I wouldn't know how to create it.
it's just the adress in the adress-bar Frits, once you are in the FOS-folder. even you should have found that one : KISS'er than that is impossible :msn-wink:.
but it didn't work as a "hyperlink" in a word document (holding ctrl while clicking it normaly opens links), so that's why you have to copy it and paste it directly in the adress-bar. since you read my manual "deeply" to find the link, I didn't say too much stupid stuff in it did I ?Taking a look in the address bar was about the first thing I tried Jan, but it didn't work for me, heaven knows why not.
But I found a method that does work: right-clicking on the desired folder will offer an option 'Get shareable link' .
343698
Once I started playing with this option, it wasn't difficult to create a direct link to the Pisa.PDF file:
https://drive.google.com/file/d/1VFLF00_SsxhHMDegPciEKE4zQ6mtjyCq/view

My first reading of your manual wasn't all that deep; I just glanced over it (lack of time, you know).
The first thing that came to mind: writing cells instead of cell's will save you a lot of apostrophes :D.

[Frits Overmars]

Frits someone ofn KB was talking about the russian nuclear ramjet cruise missle that the russians have just admited blew up and killed a heap of Russian scientists a few months ago. From a physics point of view what would a ramjet capable of mach 6 sound like. I have a suspicions its like a very loud 2t 3 cylinder chainsaw. A V1 running at 5-8 times the speed?I haven't come across that nuclear ramjet news yet, but then I haven't come across a three-cylinder two-stroke chainsaw yet either.
Assuming 8000 rpm, the latter would produce a root tone of 400 Hertz. According to Wikipedia, a V1 pulsejet could do about half of that:
https://en.wikipedia.org/wiki/Pulse_detonation_engine: "A traditional pulsejet tops out at about 250 pulses per second due to the cycle time of the mechanical shutters, but the aim of the Pulse Detonation Engine is thousands of pulses per second".
But from what I remember from German wartime footage, a V1 sputtered along at about 30 Hertz. I think I'd prefer the chainsaw sound.

[flyincat]

Here's a mildly interesting new release from the far side of the pond... it's an Arctic Cat (formerly used suzuki engines) 400cc single, C-port injected, CVT engine. The claim is 65hp, so pretty mild setup. I'm curious about the blob hanging off the bottom....water pump and balance shaft?

343699

[Frits Overmars]

https://snowgoer.com/top-stories/cat-unveiled-2021-blast-snowmobiles/28112/ :
C-TEC2 4000 power comes from a 397cc liquid-cooled, fuel-injected single that includes a counterbalance shaft to minimize engine vibration.
The engine is essentially half of Cat’s C-TEC2 8000 engine that is omnipresent in the rest of its lineup, right down to the three-stage variable exhaust.

[flyincat]

Ah yes, thanks for the detective work, Frits. It seems it would be a good power plant, as a modern two stroke entry, in the snow bike market.

343700

[Frits Overmars]

right-clicking on the desired folder will offer an option 'Get shareable link'.
343701
Once I started playing with this option, it wasn't difficult to create a direct link to the Pisa.PDF file:
https://drive.google.com/file/d/1VFLF00_SsxhHMDegPciEKE4zQ6mtjyCq/viewCome to think of it, I may have owner rights to this part of Google Drive, that you guys do not have, so I cannot be sure that the above method works for everybody.
Could you guys open https://drive.google.com/drive/folders/18l2ShH-MzrnTO0uEk9rNTk89_KgwgWof
go to the file spreuken\EN\aircraft maintenance.jpg ,
right-click this file, get a shareable link (see above picture), exit Fos Pics again and then use the shareable link to download that file,
and let me know if it works? Cheers.

[KKT]

Come to think of it, I may have owner rights to this part of Google Drive, that you guys do not have, so I cannot be sure that the above method works for everybody.
Could you guys open https://drive.google.com/drive/folders/18l2ShH-MzrnTO0uEk9rNTk89_KgwgWof
go to the file spreuken\EN\aircraft maintenance.jpg ,
right-click this file, get a shareable link (see above picture), exit Fos Pics again and then use the shareable link to download that file,
and let me know if it works? Cheers.


That would be this picture:
https://drive.google.com/open?id=1HcLTVJgCe-DHCeTK7wjgprwCyLg5jxsk Saving it directly from the link does not work, atleast not for me, i'm running windows 7 and Firefox browser.

If the url is copied to the browsers address line/ address bar, the picture shows up fine and you will be able to download/save it :)

[Frits Overmars]

Thanks KKT. If I try to copy your link, it only copies the shortened version https://drive.google.com/open?id=1Hc...jgprwCyLg5jxsk
with the three dots in the middle, and this obviously won't work in the browser.
But clicking your link instead of trying to copy it gets the picture on my screen, and then clicking the three dots in the upper-right corner gives me the download-option.
343702

So it appears that once you get the link to a Google Drive, everybody can create those shareable links, pointing directy to the files in that Drive. Good to know :niceone:.

[husaberg]

I haven't come across that nuclear ramjet news yet, but then I haven't come across a three-cylinder two-stroke chainsaw yet either.
Assuming 8000 rpm, the latter would produce a root tone of 400 Hertz. According to Wikipedia, a V1 pulsejet could do about half of that:
https://en.wikipedia.org/wiki/Pulse_detonation_engine: "A traditional pulsejet tops out at about 250 pulses per second due to the cycle time of the mechanical shutters, but the aim of the Pulse Detonation Engine is thousands of pulses per second".
But from what I remember from German wartime footage, a V1 sputtered along at about 30 Hertz. I think I'd prefer the chainsaw sound.


https://www.youtube.com/watch?v=9XLGjV_7b6s
https://hips.hearstapps.com/hmg-prod.s3.amazonaws.com/images/tory-1511993675.jpg
https://www.popularmechanics.com/military/weapons/a13978519/slam-cruise-missile-nuclear-thermonuclear/

https://www.youtube.com/watch?v=C4LR-EJazdI

https://www.youtube.com/watch?v=qLV1Ao9QkpE
OH THE 3 CYLINDER CHAINSAW

https://www.youtube.com/watch?v=Pf-KbZKZO6A
Can someone see if my albums are visible yet?

[JanBros]

With Win10 and Mozila or chromium, on my Pc there is no right-clicking possibility Frits, not a single menu opens ...

[peewee]

Here's a mildly interesting new release from the far side of the pond... it's an Arctic Cat (formerly used suzuki engines) 400cc single, C-port injected, CVT engine. The claim is 65hp, so pretty mild setup. I'm curious about the blob hanging off the bottom....water pump and balance shaft?

343699

400cc doesnt seem like enough for a track drive system. brc500 might be a better choice, maybe. then again, i like the saying ' too much is almost enough' :laugh:

[peewee]

does anyone know a good book about spark lead ? im wondering if theres a rule of thumb how to find correct spark lead or do you adjust it until a certain egt ( 650c ? ) is found

[jbiplane]

I agree so far, Niels. But then what happens?
This phenomenon even occurs in two-stroke boxer engines in which both exhaust pipes simultaneously suck from a common crankcase.

Seems my 2 in one muffler dont suffer of this problem and equalize processes in both cylinders, but cannot be sure rpm floating.
May be cause on cheapest chinese carburetors. Will try understand reasons.

https://www.youtube.com/watch?v=H2KGh3Bm238&t=15s

[Frits Overmars]

With Win10 and Mozila or chromium, on my Pc there is no right-clicking possibility Frits, not a single menu opens ...Might be another reason for me to stay away from Win10. I'm running Win7 and Firefox, and fairly happy with both.
I just tried Google Chrome. That doesn't work, but that is not really conclusive, as I've had problems with Chrome before;
it's the reason I switched to Firefox.
Anyway, it could be a matter of owner rights. As I've only got the one computer here, it's difficult to test.

[JanBros]

Might be another reason for me to stay away from Win10

I'm pretty sure it has nothing to do with Win10 and everything with you having owner rights and us not.

Win10 is incredibly trouble free and at some point you will have to upgrade from win7.

I used to think that Microsoft was the evil Big Brother in the Tech-world, I think now we all now it's Facebook (which I refuse to use) and Google (of which I use only the bare minimum : that is the search engine itself, and I have a gmail-account, because from time to time you need it for playing with mobile android phones). I don't use Google Chrome, I use the Goolge-less Chromium version (from time to time)

[andreas]

https://www.youtube.com/watch?v=9XLGjV_7b6s
https://hips.hearstapps.com/hmg-prod.s3.amazonaws.com/images/tory-1511993675.jpg
https://www.popularmechanics.com/military/weapons/a13978519/slam-cruise-missile-nuclear-thermonuclear/

https://www.youtube.com/watch?v=C4LR-EJazdI

https://www.youtube.com/watch?v=qLV1Ao9QkpE
OH THE 3 CYLINDER CHAINSAW

https://www.youtube.com/watch?v=Pf-KbZKZO6A
Can someone see if my albums are visible yet?
It says no recent activity

[OopsClunkThud]

Anyway, it could be a matter of owner rights. As I've only got the one computer here, it's difficult to test.

you can use a second browser (chrome) or even the private mode in firefox to access as a non-owner from the same computer.

[husaberg]

It says no recent activity

can you access the photos?

[andreas]

can you access the photos?

No photos, only attachmens.

[husaberg]

No photos, only attachmens.
these albums

NSR500 Porn
http://www.kiwibiker.co.nz/forums/album.php?albumid=4837
http://www.kiwibiker.co.nz/forums/album.php?albumid=4837

I will be adding some more later including
Honda RS125
http://www.kiwibiker.co.nz/forums/album.php?albumid=4841
http://www.kiwibiker.co.nz/forums/album.php?albumid=4841

Aprilia GP bikes
http://www.kiwibiker.co.nz/forums/album.php?albumid=4839
http://www.kiwibiker.co.nz/forums/album.php?albumid=4839
YZR500

Swiss auto
http://www.kiwibiker.co.nz/forums/album.php?albumid=4833
http://www.kiwibiker.co.nz/forums/album.php?albumid=4833

Rotax and other Tandem twins
http://www.kiwibiker.co.nz/forums/album.php?albumid=4840
http://www.kiwibiker.co.nz/forums/album.php?albumid=4840


RGV500

Kenny Roberts 3's

Cagiva
http://www.kiwibiker.co.nz/forums/album.php?albumid=4842
http://www.kiwibiker.co.nz/forums/album.php?albumid=4842

Carbs fuels intakes and stuff
http://www.kiwibiker.co.nz/forums/album.php?albumid=4844
http://www.kiwibiker.co.nz/forums/album.php?albumid=4844

[Flettner]

I finally got round to finishing off the wiring on the 360. A job I hate but once I'm in the zone it's not so bad.

[husaberg]

Holey shit Neil
Spaghetti for dinner.

[Frits Overmars]

NSR500 Porn
http://www.kiwibiker.co.nz/forums/al...p?albumid=4837
http://www.kiwibiker.co.nz/forums/al...p?albumid=4837

I will be adding some more later including
Honda RS125
http://www.kiwibiker.co.nz/forums/al...p?albumid=4841
http://www.kiwibiker.co.nz/forums/al...p?albumid=4841

Aprilia GP bikes
http://www.kiwibiker.co.nz/forums/al...p?albumid=4839
http://www.kiwibiker.co.nz/forums/al...p?albumid=4839
YZR500

Swiss auto
http://www.kiwibiker.co.nz/forums/al...p?albumid=4833
http://www.kiwibiker.co.nz/forums/al...p?albumid=4833

Rotax and other Tandem twins
http://www.kiwibiker.co.nz/forums/al...p?albumid=4840
http://www.kiwibiker.co.nz/forums/al...p?albumid=4840

RGV500

Kenny Roberts 3's

Cagiva
http://www.kiwibiker.co.nz/forums/al...p?albumid=4842
http://www.kiwibiker.co.nz/forums/al...p?albumid=4842

Carbs fuels intakes and stuff
http://www.kiwibiker.co.nz/forums/al...p?albumid=4844
http://www.kiwibiker.co.nz/forums/al...p?albumid=4844Not much joy there, Husa. I couldn't access those albums back in 2014, and I still can't.
343714

[andreas]

these albums

No , page suggests to mind my business.

[jbiplane]

Almost ready ECU. Missed on-board MAP sensor (delivery delay)
https://paraplan.ru/forum/files/14258/4DN83mWV.jpg

[monkeyfumi]

these albums

If I click the links in your post, I can see the albums. But if I click the same links in Frits' quoted reply, then they don't work.

[husaberg]

Not much joy there, Husa. I couldn't access those albums back in 2014, and I still can't.
343714
odd they work for me but not for your replied quote?



No , page suggests to mind my business.
these should work.

NSR500
https://www.kiwibiker.co.nz/forums/album.php?albumid=4837
Aprilia
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839

Cagiva
https://www.kiwibiker.co.nz/forums/album.php?albumid=4842

Sparton
https://www.kiwibiker.co.nz/forums/album.php?albumid=5156

RS and NS500
https://www.kiwibiker.co.nz/forums/album.php?albumid=4861

TZ750 and TZ500
https://www.kiwibiker.co.nz/forums/album.php?albumid=4932


NSR500V
https://www.kiwibiker.co.nz/forums/album.php?albumid=4953

https://www.kiwibiker.co.nz/forums/album.php?albumid=5025

https://www.kiwibiker.co.nz/forums/album.php?albumid=4841

https://www.kiwibiker.co.nz/forums/album.php?albumid=4844

[andreas]

these should work.

NSR500
https://www.kiwibiker.co.nz/forums/album.php?albumid=4837
Aprilia
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839

Cagiva
https://www.kiwibiker.co.nz/forums/album.php?albumid=4842

Sparton
https://www.kiwibiker.co.nz/forums/album.php?albumid=5156

RS and NS500
https://www.kiwibiker.co.nz/forums/album.php?albumid=4861

TZ750 and TZ500
https://www.kiwibiker.co.nz/forums/album.php?albumid=4932


NSR500V
https://www.kiwibiker.co.nz/forums/album.php?albumid=4953

https://www.kiwibiker.co.nz/forums/album.php?albumid=5025

https://www.kiwibiker.co.nz/forums/album.php?albumid=4841

https://www.kiwibiker.co.nz/forums/album.php?albumid=4844

It's working and jolly.

[Frits Overmars]

these should work.They do!


Right there is 100 odd albums in there
https://www.kiwibiker.co.nz/forums/album.php?u=28036
As Frits suggested i will be putting them likely into a cloud based file :2thumbsup

But keep them on your own hard disk as well. Remember:
343719

[husaberg]

They do!

:2thumbsup

But keep them on your own hard disk as well. Remember:
343719

I had them and heaps more on an external drive that failed.
So i can see what you are saying.

[Lef16]

Hi,
It has probably been discused here before,but I can't help my self from asking,so here it is.
What's the effect of a steeper angle in header?
Lets assume that we have an engine,and 2 almost identical exhaust pipes,2 headers at 32% as wobbly said,but one header has 3* angle and the second one has 3.5 or 4*,who is it going to affect power and power curve?
Question number 2:
Lets again assume we have 2 exhaust pipes,same header,same TL,same belly dia,but different diffuser angles,lets say in first pipe all 3 angles are close,but in the second one they are more "spread",with the first been the more shallow and the final diff been the steepest,how each one is going to perform?Who will the 2 differend diffusers spread the power?
Here's an example,because I don't know if I made my point clear(english language is not my strongest point :) )
343768
PS:I know that probably it's been discused before,somewhere in these 2200+ pages,but I dont seem to find it,no matter what.So if someone has the link that I miss,share it ;) ,if not I would really like to hear some opinions,especially from wob or frits!

[wobbly]

Engines respond differently to diffuser and header angles , but a few points for you to note.
If you have a 75% nozzle on the cylinder exit ( you haven't ) try dividing the header in 1/2 and running 3.2/5.2*.
Having a longer and steeper last diffuser leading up to the belly adds power on the front side approaching peak. A steeper 1st diffuser adds power after peak.
These designs are based on the old Honda published A kit info , they need a fatter belly diameter ( 125 at least ) and a steeper rear cone to go with that.
The good thing is you can try all this easily in EngMod and rely on the results as long as the rest of the project inputs are real.

[TZ350]

I know that probably it's been discused before,somewhere in these 2200+ pages,but I dont seem to find it,no matter what.So if someone has the link that I miss,share it ;) ,if not I would really like to hear some opinions,especially from wob or frits!

Hi Lef16 I used this search:-

header cone angles site:https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner

just copy and paste that line into Google to find a lot of references to pipe and header cone angles.

343769

The Google "site:" term before the KiwiBiker ESE threads web address is the way to find what you are looking for.

Wobbly and Frits have posted so much info about pipe design on the ESE thread that it is now a total gold mine of expert info on pipes.

[andreas]

Hi,
It has probably been discused here before,but I can't help my self from asking,so here it is.
What's the effect of a steeper angle in header?
Lets assume that we have an engine,and 2 almost identical exhaust pipes,2 headers at 32% as wobbly said,but one header has 3* angle and the second one has 3.5 or 4*,who is it going to affect power and power curve?
Question number 2:
Lets again assume we have 2 exhaust pipes,same header,same TL,same belly dia,but different diffuser angles,lets say in first pipe all 3 angles are close,but in the second one they are more "spread",with the first been the more shallow and the final diff been the steepest,how each one is going to perform?Who will the 2 differend diffusers spread the power?
Here's an example,because I don't know if I made my point clear(english language is not my strongest point :) )
343768
PS:I know that probably it's been discused before,somewhere in these 2200+ pages,but I dont seem to find it,no matter what.So if someone has the link that I miss,share it ;) ,if not I would really like to hear some opinions,especially from wob or frits!

Diffuser "horn coefficient" is the word you're looking for.

[andreas]

I read a few places about the negative effects of fitting large diffusers to old style transfer design, it resulting in 'over scavenging' assuming charge is drawn to far or contamineted to be pushed back. And the villain should be poor tr duct design and not enough backward angling -but suction wave should not create any directed flow from the ducts, perhaps more eddying at most? The reason is rather the crank volume being to small to feed the greater wave?

[lohring]

With the few pipes I've built, I found that a relatively low horn coefficient (1.2) gave the best peak power. A little higher horn coefficient (1.4) worked better on a stock, piston ported engine with a relatively restricted intake port and transfers. Modifications to the intake and transfer width and timing eliminated this advantage.

Lohring Miller

[andreas]

I agree with that, makes me think advancing the diffuser might be a possibility.

[wobbly]

You can move the diffuser forward to increase the negative pressure ratio sooner around BDC.
This helps overev power - offset by the increase in front side by the steep last diffuser angle.
Here is the new homologation R1 pipe for TM done in EngMod.

Edited - wrong final pipe design

[andreas]

This look very good I think.

[TZ350]

343809 343810

Making a bit of progress with the Kawasaki F81M inspired racer. Drilled and plugged the cylinder stud holes and relocated them to suit the Suzuki cylinder. The spacer plates will be screwed and glued to the cases and the cylinder studs will be threaded through them as well as the cases. If a KTM250 can make 48 rwhp then with methanol/acetone blend I am hoping to do much the same.

[katinas]

I finally got round to finishing off the wiring on the 360. A job I hate but once I'm in the zone it's not so bad.

Nice. Rear exhaust is what Yamaha did not developed on 2t from they 1990 YZ 250 prototype.

[ceci]

Nice. Rear exhaust is what Yamaha did not developed on 2t from they 1990 YZ 250 prototype.



I hallucinate, I thought it was legend and that it was not true.
14 years ago in a forum in my country, I read about it and that it had disappeared, since they had been stolen.
I don't remember if they said I had injection or electronic traction control

[ceci]

katinas.
This image is from the draft of the answer about the information they gave about a YZM, you will see that it is from 2005 and what I put in was:
"The only YZM of 2t that I know of aluminum are, those of Frenchman Jachy Vimond and Kurt Ljunqvist, who played the 500 World Cup of '87, the chassis was not deltabox but simple cradle unfolded at the height of the cylinder and lacked all those technological advances that count.

It is strange that because they steal the prototypes they lose all the technology, because I thought that this was reflected before on paper, which accounts have not applied anything "


They didn't put pictures like you and when you don't see things you don't believe them

[katinas]

Ceci,
Photos is from RACERS vol. 53. https://www.ebay.co.uk/itm/RACERS-Vol-53-91-92-YZM250-Sanei-Mook-from-japan-NEW/223739773100?epid=12031579021&hash=item3417ee00ac:g:57UAAOSw4O9dxGrX
On 1991 YZM 250 they use Al frame more familiar to XXI century frames , but in 1993 they revert to steel on YZM 250.

Brilliant magazine, so much interesting small details in photos and Japanese language, with translator, gives even more interest. All issues with 2t racers very informative. Latest 54 vol. is first part about NR 500.
https://www.ebay.co.uk/itm/NEW-RACERS-Vol-54-HONDA-NR500-Part-1-Bike-Magazine-Book-Japan-F-S/254384107322?epid=9034483240&hash=item3b3a796f3a:g:t-QAAOSw9-RdneEb

This is more about street 2t
https://www.neko.co.jp/magazine/2%E3%82%B9%E3%83%88%E3%83%AD%E3%83%BC%E3%82%AF%E3% 83%9E%E3%82%AC%E3%82%B8%E3%83%B3%E3%80%80vol-19

[ceci]

In this image there is a sleeve that is connected to the crankcase.
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=343812&d=1575624094

TZ350: engine it has a similar one, but it is for the MAP
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=338954&d=1537352479

[katinas]

And plugged holes under B on Aoyama s 2009 Honda RSW 250 engine.

[peewee]

katinas.
This image is from the draft of the answer about the information they gave about a YZM, you will see that it is from 2005 and what I put in was:
"The only YZM of 2t that I know of aluminum are, those of Frenchman Jachy Vimond and Kurt Ljunqvist, who played the 500 World Cup of '87, the chassis was not deltabox but simple cradle unfolded at the height of the cylinder and lacked all those technological advances that count.

It is strange that because they steal the prototypes they lose all the technology, because I thought that this was reflected before on paper, which accounts have not applied anything "


They didn't put pictures like you and when you don't see things you don't believe them

this is it. do you know if the engine still exist?

[husaberg]

this is it. do you know if the engine still exist?

As far as i know YZM was used on a heap of Works MX bikes over many years. Just as YZR is.
343831343832343833343834343835




M might be Mx
R might be Road.
F as in YZF might be Four Stroke

Not sure if they still assign OW numbers to MX bikes but they used to in the old days.
https://p.vitalmx.com/photos/forums/2019/08/02/364117/s1200_1983_CN_04_13_02.jpg

Honda use RC as a prefix

[Flettner]

Wiring complete.
Now to program some computers, 1x ignitech, 1x Link.

[Flettner]

Best its going to get

[husaberg]

Best its going to get

The Boeing 787 has about 500 kilometers of wiring.

[Peter1962]

Best its going to get

Neil, is this a TPI version 2 prototype, with 4 injectors ?

Watch out for Austrian 'observators' in you neighborhood :cool:

https://cdn3.img.sputniknews.com/images/105530/12/1055301209.jpg

[peewee]

As far as i know YZM was used on a heap of Works MX bikes over many years. Just as YZR is.
343831343832343833343834343835




M might be Mx
R might be Road.
F as in YZF might be Four Stroke

Not sure if they still assign OW numbers to MX bikes but they used to in the old days.
https://p.vitalmx.com/photos/forums/2019/08/02/364117/s1200_1983_CN_04_13_02.jpg

Honda use RC as a prefix

i thought i read the yzm 500 was only used two years on works bikes. sounds like only eight were ever made

https://motocrossactionmag.com/amp/1987-yamaha-yzm500-before-aluminum-was-cool/

[husaberg]

i thought i read the yzm 500 was only used two years on works bikes. sounds like only eight were ever made

https://motocrossactionmag.com/amp/1987-yamaha-yzm500-before-aluminum-was-cool/

of that model maybe but the 1986 YZ500 OW66 was also called a YZM as were heaps of other bikes of multiple cc's and years.
Like the 1983 YZM500 OW50

I found this 1983.
Satoru Shoji's '83 All Japan Championship winning works bike
It might be an interest to Frits and Jan
Yamaha rotary disc valve 125. OW67 or 1983 yzm125
I have not seen this one mentioned previously.
343842343843343844343846343845
it also race in the USA and by the look of it Europe

[Michael Moore]

A similar rotary valve CZ from 1983, it must have been all the rage.

[Flettner]

Haha, amateurs.

[husaberg]

A similar rotary valve CZ from 1983, it must have been all the rage.

Honda
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=251916&d=1322918391
did them as well as Cagiva.https://www.kiwibiker.co.nz/forums/album.php?albumid=5103
But i had never seen a pic of the Yamaha single only a drawing of the V4
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=303541&d=1413067510

[ken seeber]

The Boeing 787 has about 500 kilometers of wiring.

Good point Hooser, they('ll) both fly...

[Frits Overmars]

The Boeing 787 has about 500 kilometers of wiring.Whatever makes you happy. Me, I don't particularly care for this kind of electrickery. It's not KISS.
343849

[lohring]

If you think that's bad, take a look at an all electric drive model boat. Some of these wires carry 500+ amps while accelerating to 285+ KPH.

Lohring Miller
PS Some of the wires goe to test equipment.

343851

[katinas]

This man looks happier

[katinas]

And really happy guys. Riga 23S 125cc two cylinder rotary after more than 30 years.
https://www.youtube.com/watch?v=VP1KY1mBlDs

[husaberg]

And really happy guys. Riga 23S 125cc two cylinder rotary after more than 30 years.
https://www.youtube.com/watch?v=VP1KY1mBlDs

More a can of angry wasps getting shaken up rather than ripping calico.

[Flettner]

Neil, is this a TPI version 2 prototype, with 4 injectors ?

Watch out for Austrian 'observators' in you neighborhood :cool:

https://cdn3.img.sputniknews.com/images/105530/12/1055301209.jpg

I held off, having offered it to TM, thought they might be intetested, put the middle finger up KTM, but in the end no.
So bugger it, on the internet, free to a good home, whom ever wants it.
Im down to a single page of 'things to finish' then I'm off riding it, thats me being super optimistic.
I'm real keen to get into my 175 version but far too many things to finish off before that.
That would be the twin exhaust, open all hours crank case / rotary valve, four injector, balance shaft, special piston, pull start engine. YZ 250 X gearbox.

Time and money.

Allegedly I'm still owed a TM 125 TPI, January now. I'll have that engine out quick smart and replace it with what TM should have done.

[Pursang]

You can lead a horse to water.....

(but some won't drink until they're drowning ... and then it's usually far too late!)

Great work Neil..:apumpin:

Cheers, Daryl.

[jbiplane]

My list of 28-44mm throttle bodies and TPS to use for fuel injection. May be useful for somebody
http://www.reaa.ru/yabbfiles/Attachments/Trot_1.jpg
http://www.reaa.ru/yabbfiles/Attachments/Trot_2.jpg
http://www.reaa.ru/yabbfiles/Attachments/Trot_3.jpg
http://www.reaa.ru/yabbfiles/Attachments/Trot_4.jpg
http://www.reaa.ru/yabbfiles/Attachments/Trot_5.jpg

[TZ350]

.
That's great, very helpful. Thanks.

[katinas]

https://www.mcnews.com.au/1987-honda-nsr500-wayne-gardner/

[lodgernz]

A pipe question please:
Am I correct in thinking that the LAST diffuser cone will be the one actively sucking around BDC at mid-range RPM, and the first diffuser will be the one working at peak RPM?

[andreas]

A pipe question please:
Am I correct in thinking that the LAST diffuser cone will be the one actively sucking around BDC at mid-range RPM, and the first diffuser will be the one working at peak RPM?

If put in less absolute terms this is correct, the wave works over plenty crank degrees. By the time the first of a three stage diffuser is the only one in tune, I don't think there is much power left.

[wobbly]

Pretty much - the last diffuser cone angle affects power on the front side leading up to peak.
The header length combined with the first diffuser length and angle affect the overev power past peak.

[lodgernz]

Thanks guys. So I'm not losing it after all...

[jfn2]

I was reading a little the other night about rotary engines and I was wondering, is the rotary engines' port timing similar to a two strokes' port timing? I've only heard about a rotarys' port shape or additional port or peripheral ports but not about the timing.

[husaberg]

I was reading a little the other night about rotary engines and I was wondering, is the rotary engines' port timing similar to a two strokes' port timing? I've only heard about a rotarys' port shape or additional port or peripheral ports but not about the timing.

The inlet porting on a disc valve engine is asymmetrical.
it is laid out as ideal to make the best power with aceptable drivability
unlike a piston port that is best compromise that will still start and run as its inlet port timing is symmetrical.

[jfn2]

husaberg
Thanks for the quick reply. I'm sorry, I should have been clearer. I was referring to a rotary engine as in a Wankel rotary engine. My mistake.

[husaberg]

husaberg
Thanks for the quick reply. I'm sorry, I should have been clearer. I was referring to a rotary engine as in a Wankel rotary engine. My mistake.

Haha
no idea but they peripheral ports and the bridge have huge overlaps
i cant remember the saying it was something like they breath deep but very quick or something.( I have no idea how it was worded but it had most of those words)
they hold promise as they are more hydrogen friendly as they are not as prone to explode as the hydrogen tends to want to burn a little to fast.
Now mazda are finished theya re dead as they used to make and machine the housings for all the others as far as i am aware.
There was a crowd doing military gen sets and all sorts of huges ones where reliability an output are more important than fuel economy.

On the other hand my diesel ute make more HP than a 13b na RX7 ever did and travels nearly 900km on a tank something i doubt the rotary would without towing a mini tanker.

knock yourself out here
http://www.rotaryengineillustrated.com/RE101pages/4-ports101.html

https://www.rx7club.com/attachments/rotary-car-performance-77/374819d1264908980-made-chart-each-stock-engines-port-duration-overlap-renesis_duration.jpg

[jfn2]

husaberg
Thank you very much. Looks like good reading. It'll take me awhile to get my head onto this info. Again thanks.

[Frits Overmars]

knock yourself out here
http://www.rotaryengineillustrated.com/RE101pages/4-ports101.htmlClicking the other links on that page gives error messages. But all goes well if you start at www.rotaryengineillustrated.com (http://www.rotaryengineillustrated.com)

[husaberg]

Clicking the other links on that page gives error messages. But all goes well if you start at www.rotaryengineillustrated.com (http://www.rotaryengineillustrated.com)

i see your animation and raise you a see through glow one being ran on a mix of acetylene for visability


https://i.imgflip.com/3jr6yw.gif (https://imgflip.com/gif/3jr6yw)
the original RE5 manual they used for service techs has a great write up an description.
I have a copy here somewhere from a mag

[katinas]

Flow marks from reed cage on painted surface. Gap between reed cage side and housing wall 4.5mm. And interesting activity path between two petals (with just 0.6mm gap) at center.

[jbiplane]

May be a bit off topic. I saw fuel pump 3bar 35lph.
https://ae01.alicdn.com/kf/HTB1pW3kQVXXXXaFXFXXq6xXFXXX1/122522174/HTB1pW3kQVXXXXaFXFXXq6xXFXXX1.jpg?size=127631&height=600&width=600&hash=2286d7d36bf4b06a2e2934a9455e5144
They consume ~36 watt what could be a lot.
It is possible to make PWM regulation, exist expensive military micropumps...
but may be somethere exist affordable small fuel pumps? Says 8...12 liters per hour?

[jfn2]

katinas
Interesting picture! Could you put up more pics of this port?

[F5 Dave]

Some engines burn reeds more than others like TZ250 so a lot of sooty marks in inlet from reverse flow transfers. Reeds flow well out of thier sides just as they open I've read so highest pressure cleans soot off is my guess. Maybe.

[TZ350]

May be a bit off topic. I saw fuel pump 3bar 35lph.
https://ae01.alicdn.com/kf/HTB1pW3kQVXXXXaFXFXXq6xXFXXX1/122522174/HTB1pW3kQVXXXXaFXFXXq6xXFXXX1.jpg?size=127631&height=600&width=600&hash=2286d7d36bf4b06a2e2934a9455e5144
They consume ~36 watt what could be a lot.
It is possible to make PWM regulation, exist expensive military micropumps...
but may be somethere exist affordable small fuel pumps? Says 8...12 liters per hour?

These are the sort of pump I have been using. They work great.

[katinas]

katinas
Interesting picture! Could you put up more pics of this port?

Tried this today on the road and this was the best that get from this modified Honda NS 400 cylinder after five years. Still smoke of 747 in the head so cant say too much, but it works.

[Flettner]

arr, Haha, those cute reeds, but real induction.
But all joking aside, Katinas, you do some nice and intetesting work.

[husaberg]

arr, Haha, those cute reeds, but real induction.
But all joking aside, Katinas, you do some nice and intetesting work.

With an offset disc driven off that second gear you could run a very large disc valve with the disc being open over a larger area for a longer time without changing the timing or duration

[jbiplane]

These are the sort of pump I have been using. They work great.
Yes, but 35 watt consumption is too much.
Exist solutions like https://www.madhu.com/content/Main/FuelPumpController
but I dont find proven schematics. Pump consumption can be reduced up to 10 times. Returnless systems more and more used on modern cars. I believe it is even more advantageous for old carbed 2 wheelers...

[TZ350]

Yes, but 35 watt consumption is too much. Exist solutions like https://www.madhu.com/content/Main/FuelPumpController Pump consumption can be reduced up to 10 times. Returnless systems more and more used on modern cars. I believe it is even more advantageous for old carbed 2 wheelers...

Hi jbiplane. https://www.madhu.com/content/Main/FuelPumpController your link looks like a great idea, thanks.

[katinas]

arr, Haha, those cute reeds, but real induction.
But all joking aside, Katinas, you do some nice and intetesting work.

And main reed cage dimension is like mx 80cc just 45mm wide with four petals. Timing duration one Ex window 198 , A 142 , B 131, C 129.

Add video and cylinder photo from first test without C

https://www.youtube.com/watch?v=7NECfG27-sI

[wobbly]

Surely A port isnt 142*.
I see you are running a piston with angled squish, and flat top.
This I tested a while ago and it is now the new setup for the TM KZ R1 engines.
What angle are you running , I tried 4 ,7 ,10 with 38 dia flat on a 54 piston.

[Norman]

And main reed cage dimension is like mx 80cc just 45mm wide with four petals. Timing duration one Ex window 198 , A 142 , B 131, C 129.

Add video and cylinder photo from first test without C

https://www.youtube.com/watch?v=7NECfG27-sI


Katinas, this will be really interesting to follow..very creative.

[Pursang]

Hi jbiplane. https://www.madhu.com/content/Main/FuelPumpController your link looks like a great idea, thanks.

His description of the conversion of the DR350 to FI is clear and simple too!

Cheers, Daryl

[jfn2]

katinas
I understand what your doing with the extra cutouts into the transfer tunnels, but why the extra reeds? I was doing this back in the 70's with piston port engines with no reeds and if I realised any difference it was in low/mid range. I did not have a dyno then so I really could not tell. I know that if you provide a more direct route to the transfer windows it helps mid range but I added a tunnel
directly from the intake area to the transfer window on reed engines. This bypassed the transfer tunnel and seemed to work for mid range. But again, no hard facts.
Also, wobbly, check out sae paper # 931510 about piston dome shapes.

[katinas]

Surely A port isnt 142*.
I see you are running a piston with angled squish, and flat top.
This I tested a while ago and it is now the new setup for the TM KZ R1 engines.
What angle are you running , I tried 4 ,7 ,10 with 38 dia flat on a 54 piston.

Wob, A port timing is indeed 142, because I cut them with more axial angle than on std Honda NS 400 cylinder with A, B, C 130 and Ex 195. On this old fashion cylinder core there is no too much space for playing, so I do this not because I want this long timing, but because want more area for stronger suction pulse to A , when piston moves up and A, B windows works like only ones intake windows for mass flow in this concept. Maybe this is blind, but I started from this in mind.

This piston is flat top from RGV closed crankcase experiments, but before that I was tried angled squish/flat top piston dome shape about 1999 on NS 250 custom made pistons 56mm with 10 degree angle 36mm dia flat and later for NS experiments with 57mm piston 8.5 angle, 38mm dia flat.

[katinas]

katinas
I understand what your doing with the extra cutouts into the transfer tunnels, but why the extra reeds? I was doing this back in the 70's with piston port engines with no reeds and if I realised any difference it was in low/mid range. I did not have a dyno then so I really could not tell. I know that if you provide a more direct route to the transfer windows it helps mid range but I added a tunnel
directly from the intake area to the transfer window on reed engines. This bypassed the transfer tunnel and seemed to work for mid range. But again, no hard facts.
Also, wobbly, check out sae paper # 931510 about piston dome shapes.

This is not extra cutouts, its only ones cutouts. The main difference from normal scavenging engine is that crankcase space udder the piston is blocked (no usual cylinder side cutouts from crankcase to transfers. In previous cylinder photo cuts on cylinder liner lower edge is just to matches crankcase shape for isolation.) and only communicate with trans ports through this extra reeds, when piston moves down and timing edge of piston side closes all A, B, transfer windows. When piston moves up, side reed closes and all intake mass goes directly to transfers ports, because there is no other way, only through A and B to pass the moving piston. So side reeds release pressure under piston at BDC and help crate stronger puls to A and B when piston moves up.

Add simplified, more clear pic what was tested previously, without additional cutouts with reed from crank space last year.

[katinas]

Maybe too much words, but just want to say about engine reaction.

All previous tests, first with NS and second with RGV, was without cylinder side reeded cutout. But engine character with this schematic is very similar, just now with side reeds, engine goes more strongly.
If compare with std, some interesting things you can feel very clear.
Engine started more easily, from few kicks, but with std cold engine choke flooded immediately.
Works very stable at lower revs, more like four stroke.
Engine goes richer every time with this configuration, so main jet must be smaller than on std.
No usual cold engine first second gear bubbling, again like four stroke, feels like mix burned more completely. Its guessing, but maybe when the piston moves down some mix return through A,B, collided with flow from intake and build up pressure in transfer ports before they open.
Power rises in very linear way, again more like, sorry, four stroke.
Max revs higher and does not match, relatively small, one exhaust port area.

This is just feelings, but the first time finally came willingness to try all three cylinders in this way, on NS 400 engine.

[katinas]

Some photos of experiments with Wankel type engines in Russia long time ago

[jfn2]

katinas
Thank you for the Wankel pics.
Now I see what your doing with the transfers and intake. With isolating the crankcase from the transfer tunnels and intake charge are you worried about oiling the big and small end rod bearings? Especially turning 15,000+ rpms?

[katinas]

Yes I worried about this, but the same rod holds two years without trouble on mix 1 to 20/25 no less oil. And then decided to lower oil 1 to 35. Con rod big end eye wears out in two weeks completely, not from contact with rollers but from contact with cage. Crank pin still OK. So changed con rod and bearing before this test.
But anyway I will stick to what used in my racing days. Together with fuel/oil mix I use oil pump connected directly to crankcase, at the line where big end center goes. On the left handlebar, using bicycle Sram front gear shifter, with cable to oil pump. Open fully in the heat of the race, never any fail with big end. Maybe it sounded archaic but it works

They used Wankel engines not only on "very important security person" cars, but on rally cross cars too, and long time ago in Ukraine where track was very very sticky with so much alumina and normal engine twisted shafts, cars with Wankel engines goes absolutely in another level. But the main failure was sealing.

Peugeot 205 with Mazda rotary engine
https://www.youtube.com/watch?v=aVtKGvwnmvM

[jfn2]

katinas
very good about your oiling issues. Good work.
Thanks again for the wandel info, very interesting.

[katinas]

Very interesting test today with thinner transfers reed leaps. From the first test, last week, started with 0.55mm and all was fine. Today changed leaps to 0.3mm
After one of hard runs stopped to turn around and immediately felt that something changed, not as good as before. Found this, 0.3 mm leaps damage , so must revert to thicker reeds again

[husaberg]

Very interesting test today with thinner transfers reed leaps. From the first test, last week, started with 0.55mm and all was fine. Today changed leaps to 0.3mm
After one of hard runs stopped to turn around and immediately felt that something changed, not as good as before. Found this, 0.3 mm leaps damage , so must revert to thicker reeds again

Your leap is a petal in English named after a flower Petals

https://cdn.pixabay.com/photo/2017/02/23/00/06/flower-2091017_960_720.jpg
Your English is great btw.

[ken seeber]

Very interesting test today with thinner transfers reed leaps. From the first test, last week, started with 0.55mm and all was fine. Today changed leaps to 0.3mm
After one of hard runs stopped to turn around and immediately felt that something changed, not as good as before. Found this, 0.3 mm leaps damage , so must revert to thicker reeds again

Katinas,

Do you think that the petal (leap......thnx Hooser) damage was caused by:
1. With no keeper or stroke limiter, could the petal have been striking the opposite side of the transfer passage?
2. Again with no keeper or stroke limiter, maybe the petal tip velocity at the time of closure created too much impact and the material broke down?
3. Heat damage, it does look a little black or charred?

BTW, good, interesting and different stuff.


Everyone,

Have a goodie..:drinkup:

[F5 Dave]

Happy Sol Invictus :sunny:

[lodgernz]

Katinas,

Do you think that the petal (leap......thnx Hooser) damage was caused by:
1. With no keeper or stroke limiter, could the petal have been striking the opposite side of the transfer passage?
2. Again with no keeper or stroke limiter, maybe the petal tip velocity at the time of closure created too much impact and the material broke down?
3. Heat damage, it does look a little black or charred?

BTW, good, interesting and different stuff.


Everyone,

Have a goodie..:drinkup:

I've tried 0.3 CF petals in a normal reed block with stops, and they didn't last long.
0.5 CF seems to be the minimum for my engines.
Steel could be thinner I guess. Never used steel petals so don't know.

[diesel pig]

Steel could be thinner I guess. Never used steel petals so don't know.

and you don't want to, A broken fibre reed is annoying, A broken steel reed can lead to wrecked cranks and ruined pistons.

[ken seeber]

And, if you've got a spare half hour, you might find this interesting:

https://www.facebook.com/classic2strokes/videos/556611441588994/UzpfSTczNzg3NTU1MDoyNzE0NzkwNzY4NjEwMzMz/


includes, EFI, oil strategy, carbon fibre, coolant pump, Britten etc

Enjoy