#6

[F5 Dave]

Why would he? He's currently making class leading power with a great spread. Further, on a kart track a reed valve engine has to be an advantage. Disc valve engines come on real strong.

Wow that is low ex timing & 32.5 deg blowdown. Aiming for the monster grunt machine.

[jasonu]

Why would he? .

hasn't finished a race (yet)...

[TZ350]

hasn't finished a race (yet)...

As it has finished plenty of races, you should have said "It didn't finished that race ...". :D

[jasonu]

As it has finished plenty of races, you should have said "It didn't finished that race ...". :D

Fair call mate

[speedpro]

Wow that is low ex timing & 32.5 deg blowdown. Aiming for the monster grunt machine.

That particular cylinder has something I've been working on that seems to work so I'm really looking forward to getting it run in and a good pipe on it. The blowdown T/A looks real good. If it works it'll be made public. Definitely looking at a kart track type of motor but still hoping for mid 20s.

[husaberg]

Why would he? He's currently making class leading power with a great spread. Further, on a kart track a reed valve engine has to be an advantage. Disc valve engines come on real strong.

Why because he currently has class leading hp that's why. He has class leading HP because he always tries to improve number 6.
I asked if he has considered it as he seemed more than a little excited when he saw the pics of the Disk valved MB motor.

The rear half of those cases looks like an MB100, I'm not kidding. Will post photos later. There is even the little block for the engine number and the hole for the neutral switch.
The nsr top end has a power valve which would be just the ticket for smoothing out the abrupt power delivery wouldn't you think.
Frits's post's seems to point toward,s an extra 3 or so HP with no loss in power spread compared to a Full crankcase reed.


Oh yeah with regards to Kart tracks how many meeting that count are run on them now.
Wow the number are not what i would have expected for 12000rpm peak either.

[F5 Dave]

. . .The nsr top end has a power valve which is just the ticket for smoothing out the abrupt power delivery wouldn't you think.
. .
well, . . .no, I don't think the PV is relevent.

I've ridden some fast disc valve engines, but not that many I admit. But one characteristic I didn't like of all the ones I've ridden was the way they come on power. Not that they may be peaky (bear in mind I race an extreme 50), but turn the throttle & BaaaBUUHH. Maybe they aren't all like that, but a reed engine is usually easy to make smooth on the power, which matters 10x more on a kart track than a long track.


Mike seems to be making a Kart track engine. My H was built for Kart tracks & had a hard hit type power (supercross I was aiming for), but it was very controlable in the throttle response transition. that is more what I am talking about than power curve. The MB & H have slightly different exh mounting incedentally, but I have altered an MB pipe to an H before.

[husaberg]

well, . . .no, I don't think the PV is relevent.
Yeah really you are a little in the Flat earth society territory there Dave, really, a non believer in PV's:confused:


I've ridden some fast disc valve engines, but not that many I admit. But one characteristic I didn't like of all the ones I've ridden was the way they come on power. Not that they may be peaky (bear in mind I race an extreme 50), but turn the throttle & BaaaBUUHH.
I don't know if they are all like that either but, I have noticed the same thing but they seem accelerate briskly as well though when upright i always assumed it was a carburation thing? Maybe you get used to it. Personally i found it disconcerting.


The MB & H have slightly different exh mounting incidentally, but I have altered an MB pipe to an H before.

The H has the studs on a 45 and the MB is straight in line is that what you mean Dave? are there other differences with the mounting's?

[F5 Dave]

Yeah really you are a little in the Flat earth society territory there Dave, really, a non believer in PV's:confused:


I never said I was a non believer in PVs, nothing like it. I have converted my CPI barreled RZ from Pressure PVs to Wobblies YPVS actuated ones. My dirtbikes have all had PVs.



I don't know if they are all like that either but, I have noticed the same thing but they seem accelerate briskly as well though when upright i always assumed it was a carburation thing? Maybe you get used to it. Personally i found it disconcerting.

So exactly my point. GPs are held on long tracks. Kart tracks are a different beast.

[richban]

GPs are held on long tracks. Kart tracks are a different beast.

Heaps of power across a wide range of rpm seam's to work nice for both:innocent:

[F5 Dave]

of course, but even that ignores how the power comes on when cracking the throttle on from closed whilst still leant over. How's that pumper carb coming on then?:bleh:

[richban]

How's that pumper carb coming on then?:bleh:

Looks great thanks:shutup:

Need to buy a couple of main air jets and head to the dyno. No dosh so it will stay on the bench looking pretty. She is crisp and a fresh apple at the moment so won't be in a big rush till new engine is ready.

[husaberg]

I never said I was a non believer in PVs, nothing like it.
I am not trying to be antagonistic but.... you kinda did Dave..

The nsr top end has a power valve which would be just the ticket for smoothing out the abrupt power delivery wouldn't you think.

Oh yeah with regards to Kart tracks how many meeting that count are run on them now.
Frits's post's seems to point toward,s an extra 3 or so HP with no loss in power spread compared to a Full crankcase reed.


well, . . .no, I don't think the PV is relevent.????????????



So exactly my point. GPs are held on long tracks. Kart tracks are a different beast.
GP are held on long tracks were the PV is actually not so much of a huge advantage (relatively speaking) compared tighter more twisty kart track where it certainly will be a greater advantage. If you are referring only to the abrupt power delivery we have both encountered refer to the top quote.

[F5 Dave]

. . . . If you are referring only to the abrupt power delivery

Of course I am, many times. A PV isn't going to change that.

[husaberg]

Of course I am, many times. A PV isn't going to change that.

OK then, take your PV equipped bike adjust the PV it so its fully open. Now jam it in place. Then go for a ride.
I wonder if the power delivery will now be any more abrupt.:)
The other solely Disk Valved related abruptness as i said seems to have been sorted with modern technology

[koba]

OK then, take your PV equipped bike adjust the PV it so its fully open. Now jam it in place. Then go for a ride.
I wonder if the power delivery will now be any more abrupt.:)
The other solely Disk Valved related abruptness as i said seems to have been sorted with modern technology

A full powervalve NSR barreled engine will be thrashed by my 11hp MB if the PV motor is sitting on a workbench unfinished...

[husaberg]

A full powervalve NSR barreled engine will be thrashed by my 11hp MB if the PV motor is sitting on a workbench unfinished...

Nice and so very true :laugh:

I think i can only pedal a couple of HP myself:scooter:
But who said it wasn't finished yet?:msn-wink:

[Yow Ling]

Nice and so very true :laugh:

I think i can only pedal a couple of HP myself:scooter:
But who said it wasn't finished yet?:msn-wink:

I think you would be pretty fit if you could pedal 1/2 HP for even 5 minutes

To finish one must start hehe

[F5 Dave]

OK then, take your PV equipped bike adjust the PV it so its fully open. Now jam it in place. Then go for a ride.
I wonder if the power delivery will now be any more abrupt.:)
The other solely Disk Valved related abruptness as i said seems to have been sorted with modern technology
Power delivery or power transition? But you're not listening, you should spend some time racing on Kart tracks. Mike, I'm sure has thought about this quite carefully hence the purpose engine.

[husaberg]

Power delivery or power transition? But you're not listening, you should spend some time racing on Kart tracks. Mike, I'm sure has thought about this quite carefully hence the purpose engine.

Dave i can practically see a kart track from my house. This Kart Track (Coal Creek) makes any kart track you have access to in Wellywood seem like Imola or Nürburg.
I do plenty of laps there also.
I may not understand what you are trying to say,But a least i try, You seem to not bother to read posts, you seem to react to posts without first taking the time to actually read them.
I asked simply asked Mike a Question you jumped in and said that is a crap idea Why would he do that etc blah blah.


Have you looking seriously into a MB100 Disk conversion Mike, perhaps with a sleeved NSR top end?
From a previous PM with Mike



I have had a quick look a while ago but didn't follow the link to that engine. His clutch bits look exactly like what I do to fit extra plates. Now I've had a look at the MB after seeing what he's done it would be easy to convert an MB to disc valve. Not sure if it would be ideal with the diameter available for the rotary disc but I can already see a way around that.

Mike

lastly Trying to differentiate between delivery and transition. Why bother what is the point they are interrelated.

Anyway none of this has added to the Mikes thread any any constructive way.
Maybe i should count to 10 before replying to your posts:headbang:

[F5 Dave]

Maybe i should count to 10 before replying to your posts:headbang:

Maybe you should try a larger number:laugh:


lastly Trying to differentiate between delivery and transition. Why bother what is the point they are interrelated
I don't think they are. That is the point.

Within a second the difference in transition is mute & we're talking delivery. I want that second. I want that transition calm, not jerky. Maybe you're just a better rider than me, but I can't turn fast laps on a Kart track without the right power transition.


I don't think a Disc valve engine is a bad idea, that guy did a stella job on the 50. A bunch of work & indeed an option for a GP track. But clearly Mike was building a kart track variant. I play Freddie Spencer to your Kenny Roberts.

Since when did KB become about being constructive?:confused:

[husaberg]

Maybe you should try a larger number:laugh:


I don't think they are. That is the point.

Within a second the difference in transition is mute & we're talking delivery. I want that second. I want that transition calm, not jerky. Maybe you're just a better rider than me, but I can't turn fast laps on a Kart track without the right power transition.


I don't think a Disc valve engine is a bad idea, that guy did a stella job on the 50. A bunch of work & indeed an option for a GP track. But clearly Mike was building a kart track variant. I play Freddie Spencer to your Kenny Roberts.



Very clever but there's no way i will be left saddled with the Yamaha's. Even Kenny got sick of them. Freddy well just got sick ( Tendonitis i think)
I will be Doohan then. You can do Baiggi (ok you can do Cassoli as well if you want )

[F5 Dave]

I don't want to 'do' any bloke thanks all the same.:sick:

[husaberg]

:laugh:
I don't want to 'do' any bloke thanks all the same.:sick:

Whoo settle down Dave your aversion to both homosexual's and Italian's are well documented, so don't worry about it. :laugh:

Anyways, I'm not using any queer daigo .


:psst: Although William Shakespeare did have a saying about protesting ... I think he.....

Anyway time to get back to bikes i guess.

[speedpro]

There's been a bit of work going on but alas more parts have been sacrificed. Gary got a nice new TKRJ piston and the kart shop bored and honed the cylinder. They charged extra as the cylinder was well out of round and a few extra problems that took time to fix. End result was a primo job as usual. Gary's crank is back together with a new ProX rod and a new flat silver plated big end bearing and new mains as well.
Put it all together and went to the kart rack last meeting to do some laps and run it in. Gary was circulating nicely taking it easy and the bike was sounding sweet. Upped the pace a bit and a couple of laps later it nipped up exiting the hairpin. A check of the plug didn't show anything suspicious and the motor turned over smoothly. We decided to give it another go but it nipped up again in the same place. I've dismantled it and found the piston has scuffs up the intake side and the piston is now a gentle push fit in the bore. My initial thought was that the piston was faulty but after talking to Wobbly I'm now thinking that although the ignition was more or less right for top end, as determined on the dyno, there was probably too much advance in the mid range which caused detonation which has damaged the piston. If we'd just gone out and run it hard we likely wouldn't have had a problem as the motor wouldn't have spent enough time in the dangerous rev zone to cause a problem. There is marks about the pin bosses that look a bit like cracks, and probably are. It'll be back together with a new piston for next meeting and hopefuly Wobbly will find where the pipe has gone that he's designed for it.
Dave's bike seemed to be going good but is a bit down on power. I'm hoping to check his motor soon and set the compression where it should be. With a good pipe for his bike and compression and exhaust port spigot it should be good for at least a couple more hp.
Got some more exhaust port mods to do on both bikes plus my new cylinder and my mate reckons he has a small enough TIG torch to go up the ports.

[TZ350]

Gary was circulating nicely taking it easy and the bike was sounding sweet. Upped the pace a bit and a couple of laps later it nipped up exiting the hairpin. A check of the plug didn't show anything suspicious and the motor turned over smoothly. We decided to give it another go but it nipped up again in the same place. I've dismantled it and found the piston has scuffs up the intake side and the piston is now a gentle push fit in the bore. My initial thought was that the piston was faulty but after talking to Wobbly I'm now thinking that although the ignition was more or less right for top end, as determined on the dyno, there was probably too much advance in the mid range which caused detonation which has damaged the piston. If we'd just gone out and run it hard we likely wouldn't have had a problem as the motor wouldn't have spent enough time in the dangerous rev zone to cause a problem.

Sounds much like the problem we had at Taupo, where optomising the ignition advance everywhere in the rev range for WOT was a mistake, I guess we are learning all the time.

Good to see your progress, these fast strokers are starting to get sorted.

[speedpro]

I love long weekends. 3 days where I was able to visit Darren's workshop and spin up a few bits and roll up Gary's new chamber. I've machined up a proper exhaust nozzle but need to confirm the ID with Wobbly. I've also spun up an exhaust spigot and slip on piece for the pipe. The alloy is thick enough for an o-ring but in good bucket racer style I can see it being assembled with a squeeze of hi-temp red. I still need to match the spigot to Gary's cylinder but we probably won't get it back until this weekend. It'll be a sort of freehand CNC spigot.

Big thanks to Darren, for the pie and McDs as well

[speedpro]

Gary was over for a bit tonight. He fixed crash damage and I finished welding the last piece of the new pipe. I need to visit Darren and make everything as round as possible before trying to assemble the pipe onto the bike. I'll tape it all together first and then weld one piece at a time.
Got the cylinder back from the kart shop. They've made it quite a bit looser and it seems to rev a lot freer than before.
It is a bit chilly tonight but as my garage had been converted to a sleepout it is fully lined and has a low ceiling with insulation. Couple of minutes with the fan heater running and it was all cosy.
Measured the diameter of the centre section. It is a fat one at 120+mm

[speedpro]

Gary's bike survived the last meeting with some OK results but Dave's bike got rattly and then stopped whilst leading a race. Gary's pipe was looking a bit light down inside the muffler at the track. A little bit of a concern considering you can't really hold it flat out. The plug looked good though so we left it alone. Just pulled the head off to have a check and it is looking fine tuning wise with the crown of the piston a lightish tan colour to match the plug. The head needs some work but that's planned and will be done when I sort out the compression.

I've also dummied up the new pipe and it fits sweet with just one joint rotated to make it fit perfect. Hopefully Gary's pipe is reliable now and I just need to extract the horsepower.

Update on Dave's bike to come.

[Moooools]

Gary's bike survived the last meeting with some OK results but Dave's bike got rattly and then stopped whilst leading a race.

Update on Dave's bike to come.

And what a pity it was to watch him fall in front of me.:devil2:

May I just point out the 4 stroke was still fastest into the first corner and was pulling up on the pesky two stroke down the straight.:bleh:
Too bad the rider was able to match the bike.

[speedpro]

Both bikes were making less than 20hp so nothing flash. Both bikes had a history of seizing. Dave's bike was reassembled with a well used piston and a bore that had seen better days. I used Drano to remove aluminium from the bore and emery tape to "hone" it. The piston got the emery tape treatment as well. Dave says the plug looks dark after it stopped but earlier in the day his pipe was a light tan colour right to the end as well so it should have been light tan as well. It was making rattly noises so probably a bearing. He seems happy that it lasted 6 months or so. I have greater expectations and am pretty dismayed that it stopped. We'll do a proper rebuild then see how it lasts. The problem was that it ran OK and Dave could get round on it pretty good so he was happy, so after I got it going that was it.

Dave and Gary make any bike look better than it really is. A chat about how they are going is a real eye opener with talk of deliberately hauling on front brakes till the front sledges, deliberately, and it being OK as long as you already have a knee on the ground.

[koba]

. A chat about how they are going is a real eye opener with talk of deliberately hauling on front brakes till the front sledges, deliberately, and it being OK as long as you already have a knee on the ground.
Is that not normal? :msn-wink:

[Moooools]

Dave and Gary make any bike look better than it really is. A chat about how they are going is a real eye opener with talk of deliberately hauling on front brakes till the front sledges, deliberately, and it being OK as long as you already have a knee on the ground.

I'm sorry mate but that sounds like a dig at my riding. Which I will take offense to. However I would appreciate it if you clarified on what you actually meant. Do you mean to say that I am block passing them too late into the corner? Or that I am trying to scare the shit out of them?
I don't recall doing anything intentionally dodgy.

Do tell. They had plenty of opportunity to tell me this at the track, and I am not sour about taking first hand advice.

[husaberg]

I'm sorry mate but that sounds like a dig at my riding. Which I will take offense to. However I would appreciate it if you clarified on what you actually meant. Do you mean to say that I am block passing them too late into the corner? Or that I am trying to scare the shit out of them?
I don't recall doing anything intentionally dodgy.

Do tell. They had plenty of opportunity to tell me this at the track, and I am not sour about taking first hand advice.

Are i reading the same text as you cause i don't see any digs there.

[Moooools]

Would you care to explain what he is meaning then?

I may be wrong here. Hasn't been the best off days.

[sidwyz]

Would you care to explain what he is meaning then?

I may be wrong here. Hasn't been the best off days.

Mike is referring to there riding skills (purposfully losing the front but keeping it) being "above average" :drool:

don't worry mate nothing to do with your riding.

[Moooools]

Oh shit.

Apologies.
It makes sense now that you explain it. Got a bit ahead of myself there.

No doubt they are extremely talented riders. Dave had absolutely no trouble with passing me back. Could have done it in his sleep.

[Buckets4Me]

Oh shit.

Apologies.
It makes sense now that you explain it. Got a bit ahead of myself there.

No doubt they are extremely talented riders. Dave had absolutely no trouble with passing me back. Could have done it in his sleep.

Dave has had a history of sliding the frount of borrowed bike till he can get the power on and lifting the frount wheel off the ground thereby stoping the front sliding :weird:
and garys bike was I belive built to finish of old rs125 pistons (or so the story went)

both are nice guys to race with ( leave me plenty of room when passing)

[speedpro]

Well I've been real busy. Rebuilt Dave's engine with new main bearings. The original 30 year old one on the ignition side was a bit past it's "use by date". Found a good crack in the original 30 year old piston as well so took it out to 1st oversize and fitted a new (old) piston I had lying around. I still haven't done anything to make it faster. The transfers are still completely stock and the exhaust port is probably stock width but someone has squared it up a bit. Given time I'll have a look at it.

Gary's new pipe is finished and has come out OK. I had a quick check inside after one meeting on the new piston. Again it has been trying to pick up on the face below the exhaust port and also in 2 places in the intake side. At .003" clearance it's a bit surprising especially considering that tuning wise it looks close to perfect. I've run a bit of emery tape over the rub marks on the piston and chucked it all back together. Apart from the pipe it's the same as before. Both motors need the squish tightened up about .1-.2mm but the heads have to be located more precisely before that.

Looking forward to this weekend racing.

[koba]

Both motors need the squish tightened up about .1-.2mm but the heads have to be located more precisely before that.


I've worried a bit about the location of my head. (on the bike!) Do you dowel them or something?

[speedpro]

There's been a disturbance in "the force" Luke

[speedpro]

The dark side beckons . . .

[TZ350]

That looks great..... but where is the 30hp MB100 going??????

[richban]

There's been a disturbance in "the force" Luke

Don't you dare give that to Gary or Dave Shnanny.

[Bert]

There's been a disturbance in "the force" Luke


The dark side beckons . . .

Another two-stroker down... but still this is going to be very interesting; Great work SpeedPro.

But a little boys waits.:yes:

[crazy man]

finelly seen the light ! guess the zxr250 motor of mine needs pulling out and have something like that done to it

[F5 Dave]

That looks great..... but where is the 30hp MB100 going??????

in something more suitable than a 3LN to be sure. Whereas the 250 4 cylinder engine seems to fit as if it were made to be there.

[Rick 52]

Now this is cool, so looking forward to hearing it run..

[koba]

Phoar!

That's cool.
Even if it is a poppet-pooper.

[cotswold]

The dark side beckons . . .

You know what happened to them.........

Can you add it to Tee Zees weight chart?

Seriously it looks fantastic can't wait to see it running.

[speedpro]

It's coming along nicely. I only want to make sure the engine runs at the moment. I don't want to piss round only to find the engine won't run. I have the clutch all sorted and only need to mount the lever on the handlebar. I went over the carbs today and cleaned them all up and devconned the old fuel inlet and drilled a new one on the other side. I'm using the left side pair fitted on the right side and the fuel inlet was right where the frame spar is. The exhaust pipes are just bolted in with no gaskets or anything. The oil pickup is now in and the sump is ready to be bolted up. John Connor is lending me an ignition system just to get it going. Couple of hours on Darren's lathe may be needed to get the triggers mounted. I should have enough old chain here somewhere to wrap round the sprockets.

I'd love to put the supercharger on it but the frame spar is really in the way. The choices look to be either an intermediate shaft across the back of the engine driving the supercharger or putting the supercharger in the front. The turbocharger looks easier to fit but even using the RHB31 the engine is a bit small for turboing. That's a little way away yet so I haven't really looked at it.

[husaberg]

It's coming along nicely. I only want to make sure the engine runs at the moment. I don't want to piss round only to find the engine won't run. I have the clutch all sorted and only need to mount the lever on the handlebar. I went over the carbs today and cleaned them all up and devconned the old fuel inlet and drilled a new one on the other side. I'm using the left side pair fitted on the right side and the fuel inlet was right where the frame spar is. The exhaust pipes are just bolted in with no gaskets or anything. The oil pickup is now in and the sump is ready to be bolted up. John Connor is lending me an ignition system just to get it going. Couple of hours on Darren's lathe may be needed to get the triggers mounted. I should have enough old chain here somewhere to wrap round the sprockets.

I'd love to put the supercharger on it but the frame spar is really in the way. The choices look to be either an intermediate shaft across the back of the engine driving the supercharger or putting the supercharger in the front. The turbocharger looks easier to fit but even using the RHB31 the engine is a bit small for turboing. That's a little way away yet so I haven't really looked at it.

Mike i have plenty of 3LN and 2KR engine bits if you need any stuff?
ie 2 wrecked motors one model has from memory bigger mains (that could be the CBR250 though) so more suitable for de-strokeing and the cam timing is quite different between the two from memory? as well as the oil filter set up.I think one model had longer rods also?

[speedpro]

3LN had longer rods and shorter pistons. 3LN also had different sump with spin-on filter. Turns out the filter for the Legnum is a perfect fit on the FZR.

[husaberg]

3LN had longer rods and shorter pistons. 3LN also had different sump with spin-on filter. Turns out the filter for the Legnum is a perfect fit on the FZR.

Are you planning to metal spray the crank and offset grind?
I found a dished piston from a Honda 70 or 90 that was workable with the head? Couldn't find anything suitable in forged Unless custom

[Grumph]

Are you planning to metal spray the crank and offset grind?
I found a dished piston from a Honda 70 or 90 that was workable with the head? Couldn't find anything suitable in forged Unless custom

Summit Engineering in Rotorua used to have the right gear to do submerged arc welding on cranks - at the time they were the only ones who could do it. I understand they sold the gear to their main customer - a dairy factory or timber processing plant i heard.

I'd be interested in hearing if anyone knows of someone else who can do it.

And no Hus...metalspraying doesn't do it for me. Been there, tried that.

[husaberg]

Summit Engineering in Rotorua used to have the right gear to do submerged arc welding on cranks - at the time they were the only ones who could do it. I understand they sold the gear to their main customer - a dairy factory or timber processing plant i heard.

I'd be interested in hearing if anyone knows of someone else who can do it.

And no Hus...metalspraying doesn't do it for me. Been there, tried that.
what were they making repairing with it? reactors..................
lead in your pencil Greg?<_<

Yeah...... you maybe, had bad luck or likely bad result with metal spraying Greg but it was good enough for F1 engine cranks it can't be all that bad can it?
It could be mute anyway, regrinding those cranks won't be easy.........
I guess Mike will try to get it running on std bore and stroke first to test the engine before he commits

[Farmaken]

I used to run that Gleason submerged arc machine at Summit - it is still in Rotorua and still working . The guy who owns it now is also ex Summit and it is still being used.

Can get his contact details if anyone is interested.

[speedpro]

The original idea a long time ago was to get this engine going to test concepts.

The original goal was a v-twin with cylinder heads made from cylinders 1 & 4 off an FZR with inlets in the middle. Cam drive and engine management triggers on one side and a CVT on the other. A custom crank running the rods side by side. I was going to supercharge it and use full engine management. I still have the Haltech engine management system and after 2 years managed to get an Aisin 300cc supercharger from Japan. Funny how others are looking at CVTs now. I really need to get on with my ideas when I have them rather than 10 years later.

I had an idea for a bucket front end to get around the incredibly flexible forks. I never did make it but BMW released bikes with essentialy what I was thinking of 2 years later. I still want to make a sheetmetal girder style front end along those lines though I might let someone else be the first to ride it.

[Grumph]

I used to run that Gleason submerged arc machine at Summit - it is still in Rotorua and still working . The guy who owns it now is also ex Summit and it is still being used.

Can get his contact details if anyone is interested.

Yes, please....

[Grumph]

what were they making repairing with it? reactors..................
lead in your pencil Greg?<_<

Yeah...... you maybe, had bad luck or likely bad result with metal spraying Greg but it was good enough for F1 engine cranks it can't be all that bad can it?
It could be mute anyway, regrinding those cranks won't be easy.........
I guess Mike will try to get it running on std bore and stroke first to test the engine before he commits

Two metalsprayers in ChCh - fail both times....it may work on F1 cranks (though I doubt it) but away from the specialists who do nothing else day in day out we're fucked. Population base size again....

If - as a customer of mine does - you wsh to duplicate the now rather old Norton twin crank that has had the big end journals built up from 1.5in OD to 1.75in OD to use Commando rods....submerged arc is the ONLY way to do it.

[husaberg]

Two metalsprayers in ChCh - fail both times....it may work on F1 cranks (though I doubt it) but away from the specialists who do nothing else day in day out we're fucked. Population base size again....

If - as a customer of mine does - you wsh to duplicate the now rather old Norton twin crank that has had the big end journals built up from 1.5in OD to 1.75in OD to use Commando rods....submerged arc is the ONLY way to do it.

Yes it was in the UK I will post it if i can find it. Admitidly it was an odd reson why they used to do it though:yes:
But why in the North Island did they need the submerged Arc for a Mill or Factory its not your normal bit of kit now is it.

[Grumph]

Yes it was in the UK I will post it if i can find it. Admitidly it was an odd reson why they used to do it though:yes:
But why in the North Island did they need the submerged Arc for a Mill or Factory its not your normal bit of kit now is it.

I was told some rambling story about some f'n enormous piece of kit which had the crucial bit wearing out frequently....the critical piece was apparently priced accordingly so repair rather than replacement made economic sense.

farmaken may be kind enough to dredge his memory to oblige....

[husaberg]

I was told some rambling story about some f'n enormous piece of kit which had the crucial bit wearing out frequently....the critical piece was apparently priced accordingly so repair rather than replacement made economic sense.

farmaken may be kind enough to dredge his memory to oblige....

Niro power dryer bit maybe they are f-ing huge and incredibly expensive..... thats a stab in the dark that one as i am plainly all hot air Farmaken should get that one<_<

ps havn't found the article but eventually it will turn up.

[Farmaken]

Don`t know about the milk dryer Husa, but we did some big crankshafts and welded all sorts of things with the gleason - makes a nice job of truck driveshafts

Grumph - PM sent

[speedpro]

The 125 twin runs.

Observations - it's really cold blooded. Even with the choke pulled it still won't take throttle. It's REALLY hard to start and you sweat a LOT trying. It has a little water leak between the block and head in front of what used to be #3 and is now #1. The little bosses inserted into the end of the cams have a 6mm thread in them to allow mounting of sensors etc. These threaded holes are drilled right through. When you push the bike fast enough oil squirts out the holes. The motor runs really smoothly with no obvious vibration when revving it a bit and if you can catch it on the throttle when blipping it the engine revs sweetly to at least 10,000rpm. With the coolant just running through some hoses between the inlet and outlet it warms up really quick.

At present I would say it has a bit of potential. Not enough to be a winner but enough to be interesting. I'll sort out a radiator, check the timing, have a play with the carbs, and build a pipe for it, later. I think the idea will be to take it to the track for a ride and if it's OK carry on with development - injection, super or turbo charging, and whatever.

[TZ350]

Good work Speedpro.

[Rick 52]

Full marks ,very cool

[Sketchy_Racer]

Turbo it!, then we'll have two forms of forced induction buckets running in the North Island. I just finished the design for Mk 2 centrifugal supercharger today so will make a start on that next week.

[Moooools]

Yeah turbo it.

And don't skimp on an ECU either. Get a Link Storm. It is a bit bulky for a motorbike but can do all sorts of useful stuff. Most importantly: Antilag. Also NZ made and have excellent customer support.

[crazy man]

Turbo l think is the way to go. my mate turboed a near stock rz 350 and made 150 rear hp but before he did that he super charged it and found it a wast of time. (l did not want to put this to put glen of cause you never know) ...he thinks the small motors suck way to much hp to make it work right . but the turbo he used was a verable vane one which at high rpm they fall over and let the exhaust work better. but over 2k of turbo

[crazy man]

l know years ago a bucket sidecar had a supercharger on it but it ran another motor on it which is within the rulzs

[TZ350]

l know years ago a bucket sidecar had a supercharger on it but it ran another motor on it which is within the rulzs

Right on .... I had been looking at that too.... driving the supercharger with a donkey motor. Something from a weed eater might do the trick.

[speedpro]

Had to pull a cover off to check an oil leak so took a few pictures. You can see where the head has been sliced off through the tappet bores and ports. It was cut here so cam lobes could be ground down for the seals to run on as I wanted to be able to mount cam speed sensors for an ECU. The plate is mounted using a couple of 8mm cap screws into alloy of the head plus two 6mm screws into the cam bearing caps at the top. The seals fit over the cam and are then held pressed into the recesses in the end plate by the round caps. I didn't try and make the plate recesses exactly concentric with the cam centres as I figured I couldn't get it good enough for the seals to work properly. The seal to the end plate is between the plate and the end of the seals rather than their circumference.

I ran it again this afternoon after a few changes. You can see it in the video. After this I checked the oil and it was a lovely milky white slime. I thought there was also gas blowing through the water as it circulated. Obviously the head is going to have to come off as my homemade gasket isn't doing the job.

All the maching was done on a crappy old lathe I used to own and a simple drill press. Any grinding was done using my electric high speed grinder mounted on the tool post in a bracket I made, and taking really small cuts. There's probably some reason for not doing that but the end result was pretty good. I had covers over the bed.

http://www.youtube.com/watch?v=KGlP3oIBhuc

[F5 Dave]

Turbo l think is the way to go. my mate turboed a near stock rz 350 and made 150 rear hp but before he did that he super charged it and found it a wast of time. (l did not want to put this to put glen of cause you never know) ...he thinks the small motors suck way to much hp to make it work right . but the turbo he used was a verable vane one which at high rpm they fall over and let the exhaust work better. but over 2k of turbo

a hundred and fifty?!?? a hundred and fifty is 3x the stock. I didn't think 2 stroke turbos could be that efficient or stay together at that sort of level?

[crazy man]

a hundred and fifty?!?? a hundred and fifty is 3x the stock. I didn't think 2 stroke turbos could be that efficient or stay together at that sort of level?had expashion chambers and fuel injected . he copyed it out of a book what somone else had done . he is a turbo , injection specialtist so know what he was doing

[Sketchy_Racer]

Had to pull a cover off to check an oil leak so took a few pictures. You can see where the head has been sliced off through the tappet bores and ports. It was cut here so cam lobes could be ground down for the seals to run on as I wanted to be able to mount cam speed sensors for an ECU. The plate is mounted using a couple of 8mm cap screws into alloy of the head plus two 6mm screws into the cam bearing caps at the top. The seals fit over the cam and are then held pressed into the recesses in the end plate by the round caps. I didn't try and make the plate recesses exactly concentric with the cam centres as I figured I couldn't get it good enough for the seals to work properly. The seal to the end plate is between the plate and the end of the seals rather than their circumference.

I ran it again this afternoon after a few changes. You can see it in the video. After this I checked the oil and it was a lovely milky white slime. I thought there was also gas blowing through the water as it circulated. Obviously the head is going to have to come off as my homemade gasket isn't doing the job.

All the maching was done on a crappy old lathe I used to own and a simple drill press. Any grinding was done using my electric high speed grinder mounted on the tool post in a bracket I made, and taking really small cuts. There's probably some reason for not doing that but the end result was pretty good. I had covers over the bed.

http://www.youtube.com/watch?v=KGlP3oIBhuc

Nice work in there, the only reason for not using a grinder on a lathe is just the grinding filings wear out the slideways after time but for small home lathes no problems. Mine often gets that sort of abuse.

What did you do with the crank, did you just pull the rods out or did you also cut that in half?

In the video it sounds like the engine feels free enough to run happily, just sounds like fueling issues to me.

[speedpro]

I hacksawed the crank between #2 big end journal and the inside main bearing then chucked it in the lathe with the fixed steady on the main bearing over one and turned down the remains till it was a nice round boss, just in case I want to mount something on it. I left the cases uncut as they are real thin and light so seemed no benefit seeing as the oil and water pump stick out past the end of the cases anyway. I have thought of sealing off the inside of the cases on that side and running a supercharger off that end of the crankshatf. Looking at it tonight however "if" I went the supercharger way I'd mount it out the front and run the ex pipes somewhere else.

[koba]

Nice.
I remember when my old GSXR250 dropped a LT wire to the coil I rode it around 10KM 'till I could get enough light at a petrol station to work out and fix the problem.
It wasn't all that slow, even working against the compression of two cylinders.

[speedpro]

The water in the oil is a problem, obviously. I've had a think about the source and it can only be from maybe two places. First is the oil pump to water pump connection though I can't fully remember how that all fits together. It will however be easy to check. The other is the head to cylinder joint next to the cam chain tunnel. Easy to get to but a pain to reassemble. I took the cam cover off tonight and snapped a few photos. They show just what a nice bit of gear these engines really are. You can also see how the end cam lobe is now a round shape for the oil seal plus the alloy boss jammed into the end of the cam and then machined down.

I also noted the cam timing. When I was building this engine I took the cams to Franklin Camshaft Services who as it turns out were very friendly. The guy mapped the cam profile and suggested cam timing for a forced induction engine using these cams. You can see in the photo the holes in the cam end bosses. These are supposed to be lined up with the gasket surface. These are not. The exhaust cam is retarded and the intake is advanced about the same amount with the effect of increased overlap. If I take it apart I'll have to check the lobe centres as I don't recall the numbers it's setup to. For some reason 105degree centres rings a bell. I'll find out tomorrow.

What I'll probably do is reassemble it with standard compression and cam timing and run it normally aspirated for testing purposes.

[Grumph]

The FZR heads like 103 inlet,104 ex lobes centers.

IMO roots blowers can work well - ours did - but appropriate sizing is necessary. Big run slowly is much more efficient than small run very fast....
Sketchy, don't be offended but IMO you went too small to start with and i have the suspicion that the new idea may also be too small for the rev range it will achieve...

A 300cc roots on this run at 1:1 should give around 12lb boost hot.

[speedpro]

I've decided to pressurise the cooling system and see where it runs out - obvious once I'd thought of it.

1:1 on the blower gives 12lbs boost? Seems a bit low given 300cc/rev into 125cc/2revs but I have no direct experience with sizes, drive ratios, and the results. I figure on only spinning the engine to about 15,000rpm which may be a bit fast for the supercharger but I really don't know what they are capable of, less than 15,000 I would have thought.

Hopefully I will be able to measure the centres tonight and compare to your suggestions. Will also measure centres as installed according to Yamaha.

[speedpro]

Talking of superchargers, my mates car had a 14/71 magnesium high helix on it. The engine was around 505cu in and would pull boost at a fast idle around 2,500rpm with no load. I doubted it when he told me but one day we were running it up with a new sheetmetal manifold and as he brought the revs up a small jet of methanol shot out of a pin hole in a weld. Even at 11:1 compression the supercharger was overdriven about 15% and boost was heaps. Gotta love methanol.

I ran my turbo bike up to 19lbs at the old Taupo track one day. It would wheelstand anywhere in any gear just by opening the throttle. All good until the bottom case cracked through #2 mainbearing support.

[Sketchy_Racer]

The FZR heads like 103 inlet,104 ex lobes centers.

IMO roots blowers can work well - ours did - but appropriate sizing is necessary. Big run slowly is much more efficient than small run very fast....
Sketchy, don't be offended but IMO you went too small to start with and i have the suspicion that the new idea may also be too small for the rev range it will achieve...

A 300cc roots on this run at 1:1 should give around 12lb boost hot.

I would agree now I have built and tested the blower, ironically I built it as I believed that the 300cc/rev output of the AMR300 was too much and outside the window of efficiency and weight, but turns out it would work almost perfect for our application.

The new design if anything looks like it will be too large in terms of mass air flow and the motor running at a 2.0 pressure ratio is right on the edge of the surge line. But, I have got smart since the last blower and the gearbox I am building will also accept a compressor wheel and compressor housing from another turbo quite a bit bigger if I need to go up in size without having to make the whole thing from scratch.



I've decided to pressurise the cooling system and see where it runs out - obvious once I'd thought of it.

1:1 on the blower gives 12lbs boost? Seems a bit low given 300cc/rev into 125cc/2revs but I have no direct experience with sizes, drive ratios, and the results. I figure on only spinning the engine to about 15,000rpm which may be a bit fast for the supercharger but I really don't know what they are capable of, less than 15,000 I would have thought.

Hopefully I will be able to measure the centers tonight and compare to your suggestions. Will also measure centres as installed according to Yamaha.

This is the formula that I used for calculating boost pressure with a roots blower.

Stolen from http://victorylibrary.com/supercharger/super-drive4.htm

R: drive ratio (supercharger RPM ÷ engine RPM).
C: engine displacement, either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387.
B: boost, in pounds per square inch (psi).
A: Atmospheric pressure, in pounds per square inch (psi); 14.7 is approximately correct for sea
level and 70° F. Click for a Table of atmospheric pressure at higher elevations: ). Please
note that RAD is preferred to actual pressure when calculating the effects of air conditions on tuning.
V: supercharger volume in either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387
per revolution; Roots volume is “displacement”, eccentric vane volume is “swept volume”.
O: Cam overlap; subtract 30 from the overlap in degrees, then multiply by 1% (.01). E.g. for 65°
overlap, O = 65 - 30 = 35, × 1% = .35.

R = C × (B + O + A) / V × 2 × A

[husaberg]

I would agree now I have built and tested the blower, ironically I built it as I believed that the 300cc/rev output of the AMR300 was too much and outside the window of efficiency and weight, but turns out it would work almost perfect for our application.

The new design if anything looks like it will be too large in terms of mass air flow and the motor running at a 2.0 pressure ratio is right on the edge of the surge line. But, I have got smart since the last blower and the gearbox I am building will also accept a compressor wheel and compressor housing from another turbo quite a bit bigger if I need to go up in size without having to make the whole thing from scratch.




This is the formula that I used for calculating boost pressure with a roots blower.

Stolen from http://victorylibrary.com/supercharger/super-drive4.htm

R: drive ratio (supercharger RPM ÷ engine RPM).
C: engine displacement, either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387.
B: boost, in pounds per square inch (psi).
A: Atmospheric pressure, in pounds per square inch (psi); 14.7 is approximately correct for sea
level and 70° F. Click for a Table of atmospheric pressure at higher elevations: ). Please
note that RAD is preferred to actual pressure when calculating the effects of air conditions on tuning.
V: supercharger volume in either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387
per revolution; Roots volume is “displacement”, eccentric vane volume is “swept volume”.
O: Cam overlap; subtract 30 from the overlap in degrees, then multiply by 1% (.01). E.g. for 65°
overlap, O = 65 - 30 = 35, × 1% = .35.

R = C × (B + O + A) / V × 2 × A

i came up with .5 engine speed 1.5 bar 0r 22psi ( assuming 100cc engine 300cc rootes blower) using less sophisticated formula?
which was within the limits of H2O avgas and intercooling....... just.

I've decided to pressurise the cooling system and see where it runs out - obvious once I'd thought of it.

1:1 on the blower gives 12lbs boost? Seems a bit low given 300cc/rev into 125cc/2revs but I have no direct experience with sizes, drive ratios, and the results. I figure on only spinning the engine to about 15,000rpm which may be a bit fast for the supercharger but I really don't know what they are capable of, less than 15,000 I would have thought.

Hopefully I will be able to measure the centres tonight and compare to your suggestions. Will also measure centres as installed according to Yamaha.
interesting to see how the valve timing clocks against the factory figures...... did you do yours at 1mm lift Mike?

I found the 3ln vs 2kr factory figure for timing and duration. ............seems the cam are probably the same only inlet is advanvcef 4 degress on the 3LN and the exhaust retarded 1 degree plus the carbs are 2mm bigger as well. interestingly the plugs are hotter?

[speedpro]

Finally got round to measuring the cams. Everything checked at least twice.

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 139deg ATDC and closes at 2deg BTDC
Intake is centred at 105.5deg ATDC, measured at 1mm lift it opens at 13deg BTDC and closes at 48deg ABDC.

The numbers seemed odd and not what I remembered. Anyway I had a look around inside and found the original readout sheet from Franklin Cam Services. It was dated 11:44AM Thu Jul 6 2000 to give you an idea how long this engine has taken to get into a bike. The suggestions were:

Exhaust centred at 110deg BTDC
Intake centred at 105deg ATDC.

Little bit out but obviously the intention was there. I'll adjust it tomorrow and measure the timing with the cams installed where they should be, if I can be bothered. Lift is 5.2mm ish. It's near impossible to get the DTI onto the buckets and I had to use a match screwed into my DTI to get down past the cam caps and the lobes.

[Grumph]

Where you're checking bucket and shim cams, it's a good (if drastic) idea to cut a free end of the cams off level with the outside lobe.
Doesn't matter which end.
This gives you a clear shot at a bucket.

[speedpro]

I'm familiar with the technique. In this case the "free" end is the exposed end on the other side of the camchain and isn't there any more. On my old CB360 I had a cam cover that was half missing alowing access to the valve gear and the cam sprocket.

[speedpro]

I pulled the water pump off and plumbed a loop of tubing to it, filled it with water and pressurised it to 10 lbs. There were no leaks from the pump. Now I've pulled the head off. There was nothing really obvious and it did look to have been sealed up pretty good. It did show that I need to put a few more water holes in the copper gasket. I seem to remember dropping the sleeves out for some reason, possibly to machine the wire receiver grooves into them and the other possible path for water is between the sleeve and alloy of the block. It has o-rings around the bottom of the cylinders on each sleeve but as they aren't compressed in any way I don't see how they could form a seal. Only the base gasket holds them in. I might drop the sleeves out and see if I can fit an oring at the top to seal the water in. Loctite might have some sort of wicking in sealant that might be useful as well.

I also thought the head bolts weren't as tight as they could have been. I'll have to check correct values and add a bit when reassembling. It may have just been they required to be retorqued after being run.

I'm gonna get into this as 12 years so far is too long from bench to bike for an engine. Who knows I might even have a look at the other bike as well. It's been about the same time for that as well. Might need a secret off-shore account. Of course having some money to put in it would help.

[husaberg]

Finally got round to measuring the cams. Everything checked at least twice.

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 139deg ATDC and closes at 2deg BTDC
Intake is centred at 105.5deg ATDC, measured at 1mm lift it opens at 13deg BTDC and closes at 48deg ABDC.

The numbers seemed odd and not what I remembered. Anyway I had a look around inside and found the original readout sheet from Franklin Cam Services. It was dated 11:44AM Thu Jul 6 2000 to give you an idea how long this engine has taken to get into a bike. The suggestions were:

Exhaust centred at 110deg BTDC
Intake centred at 105deg ATDC.

Little bit out but obviously the intention was there. I'll adjust it tomorrow and measure the timing with the cams installed where they should be, if I can be bothered. Lift is 5.2mm ish. It's near impossible to get the DTI onto the buckets and I had to use a match screwed into my DTI to get down past the cam caps and the lobes.

the exhaust timing should that be

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 39deg BBDC1̶3̶9̶d̶e̶g̶ ̶A̶T̶D̶C̶ and closes at 2degB̶T̶D̶C̶ ATDC?

[speedpro]

the exhaust timing should that be

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 39deg BBDC1̶3̶9̶d̶e̶g̶ ̶A̶T̶D̶C̶ and closes at 2degB̶T̶D̶C̶ ATDC?

Nope. Measured at 1mm lift.

At .1mm it opens at 115deg ATDC and closes at 23deg ATDC.

This is considerably retarded from stock though exactly how much I haven't measured. The setup was for a forced induction engine which has always been the intention. The other side is that the intake cam is advanced.

[Pickle]

. Might need a secret off-shore account. Of course having some money to put in it would help.

Think I can help you there - just send money

[speedpro]

Got a radiator plumbed in and held on with bits of string, just to get it going. So much to do after I get it running.

And then today a box turns up on the doorstep before I went to work. More watercooled bits with the start of hopefully some very trick porting. It's going to be very hard to concentrate on just one thing.

[F5 Dave]

So are you going to run U tube between the head & barrel, or separate rads?

[koba]

Got a radiator plumbed in and held on with bits of string, just to get it going. So much to do after I get it running.

And then today a box turns up on the doorstep before I went to work. More watercooled bits with the start of hopefully some very trick porting. It's going to be very hard to concentrate on just one thing.

Have you run inlet auxillary inlet ports like that before?

I thought I may have pused mine out too far in my latest grinding frenzy but they aren't that far out.

[speedpro]

As long as the piston has support at the rear it shouldn't be a problem. I have always had similar porting on MB100s.

[speedpro]

Went to JC's this arvo and had a play on the dyno. It most surely did not want to go. In the end we had it sorted a bit and could start it with no drama. I'm running the standard CV carbs and they need a finger down each just to the slide which makes them respond to throttle. It was so bad I took the cam cover off to double check the cam timing. It looks good, the timing marks are pretty close to perfect, but I've decided to measure it properly anyway. We pulled the revs up quite high without load and it sounds sweeeeet and revs pretty freely. I'm going to have a look at the sense hole in the bottom of the slides and may try drilling them out a bit. I had a pair of CV carbs on another bike with no airbox and they were awesome carbs and only made 2hp less right at peak compared to mega$ smoothbores according to the guy I bought it off. Giving it throttle at low speed resulted in standoff out the carbs about 20cm. We checked blowdown just to see and it was all good. It looks like it'll be good so will perservere with it.

[crazy man]

so did you have a airbox on it or not? would say you would have to go to about 135-140 main jets without the airbox

[speedpro]

no airbox. The problem is way down the rev range just as you open the throttle. Haven't got to the mains yet. I know from experiance in the bike shop that these carbs are a problem even on a stock bike. FI or a simple manifold with a single newer carb would simplify things. I need to try tuning it before I ditch the stock carbs though.

[Sketchy_Racer]

no airbox. The problem is way down the rev range just as you open the throttle. Haven't got to the mains yet. I know from experiance in the bike shop that these carbs are a problem even on a stock bike. FI or a simple manifold with a single newer carb would simplify things. I need to try tuning it before I ditch the stock carbs though.

If they are CV carbs they need trumpets or airbox on them. They wont open the throttle slides at low RPM with the correctly directed air flow.

[crazy man]

both my nc30 and zxr with cv carbs with no air box dont rev out under load but seem fine with no load

[koba]

I wouldn't bother, there are many cheap slide carbs about that would be OK on a 125 4V cylinder to get them going...

[speedpro]

Another lesson learned. Actually it's an old lesson that I have been reminded of. I've measured the cam timing as installed using the marks. It was way off and made no sense. Amazing it ran actually it was so far off, with the intake closing VERY late, hence the blowback from the carbs. I spent a bit of time trying to find why and finally found it. The holes in the end bosses which I used as timing marks aren't timing marks. They are probably used in the manufacture of the cams as the holes line up with the lobes.

The timing marks are actually little indents in the outer rim of the bosses on the end of the cams which line up with little nipples on the top of the cam bearing caps on the left of the engine. The left of the engine is gone but the cams still needed to be located in the head so I flipped them over. They now actually rotate backwards compared to original. It's OK as the cam lobes are symmetrical. The problem is that I can't line up the proper timing marks as when the cams are installed originally the lobes will be at a certain angle and the valve stems and tappets are at another angle. With the cams flipped over the lobes are still the same angle but from the cams point of view the vavle angle is now in the other direction. I have to make an allowance of twice the valve inclined angle.

I had to give it up earlier as it was doing my head in. I've found the problem though so it's just a matter of getting it back together properly, and measuring it to make sure. I'll punch a mark in each bearing cap for cam alignment once I have it sorted.

[Grumph]

Ha - normal yamaha....They're masters of three things.

Timing marks you have to search for - hard.

The last hidden bolt in the cases....

Orphan bearings - I've had a theory for decades now that a yamaha designer has a brother in law who owns a bearing company.

[speedpro]

Cam timing all sorted. It seems that Yamaha measure their timing at .2mm. It's ended up at about where it was originally setup which is no real surprise. The intake is now advanced about 45 crankshaft degrees and the exhaust is retarded about the same amount.

I had a look at the carbs and moved the needle up one as it seemed lean to me just as the slides came up. It started fine at about the 4th push and revved a bit better. Took it to JC's this arvo and ran it up on the dyno. It fired up OK and seemed to rev OK without load but wasn't happy having to work. John retarded the timing which helped it take throttle under load. We did one run which sounded OK to a point. The slides moved up as the revs rose and than stalled as the motor hesitated badly. It made a whopping 3hp. I thought it was running lean so chucked bigger mains in. Next run saw the slides move fully up though #2 seemed to stick at about 3/4. Finally as the revs climbed it popped fully open. The motor finally pulled decent revs and was starting to sound serious. This time it had about 8hp I think. After a couple of bigger mains we had it making 13.?hp and revving real clean. John has had 600s on the dyno and builds the mighty JCR CB150Ts which rev pretty hard. Even he was impressed with the revs and suggested a tacho might be a good idea. I was wondering a bit myself. The power only dropped off when I shut the throttle after chickening out. It has huge standoff, about 2-300mm when on song. The carbs are open with no stacks or airbox. We had to call it quits after an o-ring failed on a coolant pipe and it sprung a leak.

Anyway it seems like it will be good enough to try as it is though an airbox would be ideal. After a couple more dyno runs, jets and timing it should be good to go.

I check out the EcoTrans system for the Ninja 250R. The throttle body will drop straight in as the dimensions are spot on and I'm hoping with a 3bar MAP sensor it'll handle running boost.

With standard FZR250 gearing it pulled to over 160K. Definitely going to need an even bigger rear sprocket.

[speedpro]

The new engine has been tweaked but the carbs are still a problem as they don't respond properly to throttle and revs. We can tune them and get good responses on the dyno but they aren't right. I've parked it until I can get the fuel injection and engine management installed. There's a video but it cuts out at 15,???rpm as the camera didn't like the noise in the room. Currently the pipes are just a length of pipe on each cylinder. The power climbs all the way to 18,000rpm. The engine likes 10,000rpm to get the roller turning in first but is quite happy at 4-5,000rpm after that. At full throttle the carb slides start to pick up at about 5,000rpm and don't top out until about 14,000rpm and #1 beats #2 to top by about 2,000rpm so obviously a lot of work required there. I've always intended FI so this seems a good time to go for it.

http://youtu.be/3hwezxF-Jmo

[goose8]

I would like to thank Mike Green for letting me use his motor, an Dave Manuell for letting use his bike now the fun starts getting the motor in and everything together before the gp Team Shnanny Green is going to give it a good crack this year.
Cheers Gary

[richban]

I would like to thank Mike Green for letting me use his motor, an Dave Manuell for letting use his bike now the fun starts getting the motor in and everything together before the gp Team Shnanny Green is going to give it a good crack this year.
Cheers Gary

Shit........

[koba]

I would like to thank Mike Green for letting me use his motor, an Dave Manuell for letting use his bike now the fun starts getting the motor in and everything together before the gp Team Shnanny Green is going to give it a good crack this year.
Cheers Gary

Hmm, if this is the 30hp jobbie it could get interesting!

[ac3_snow]

Awesome! there is going to be a lot of fast bastards on very quick bikes by the sounds of it.

[Rick 52]

Haha Great news Gaz, I know who to vote for now :niceone:

[bucketracer]

This has to be one of the most exciting GP's

[TZ350]

Awesome! there is going to be a lot of fast bastards on very quick bikes.

Ditto 2 what he said, this is the must see GP.

[speedpro]

Couple of hours ar Darren's last Sunday making brackets, 1-2 hours each night Mon-Thu after work and all day today, 7:30-4, but it's ready. Gaz bought a new shock(with damping) so it should handle a lot better and let him get on the power earlier.:apint:

[husaberg]

Couple of hours ar Darren's last Sunday making brackets, 1-2 hours each night Mon-Thu after work and all day today, 7:30-4, but it's ready. Gaz bought a new shock(with damping) so it should handle a lot better and let him get on the power earlier.:apint:

That radiator seems rather Big for a thermosiphon head only setup? ductape?
I love the look of those Aprilia chassis, they seem to mimic the GP 125 for geometry to i think.
Back old school it was all bigger engines in smaller light chassis we seem to be making stuff stiffer but heavier now?

[Sketchy_Racer]

Yeeeahh buddy, can't wait to see/hear about the GP with garry on that and richban on his FXR, it's going to be ferral out there, gutted my bike is so far away from being ready to race. Damn work!

[husaberg]

Another lesson learned. Actually it's an old lesson that I have been reminded of. I've measured the cam timing as installed using the marks. It was way off and made no sense. Amazing it ran actually it was so far off, with the intake closing VERY late, hence the blowback from the carbs. I spent a bit of time trying to find why and finally found it. The holes in the end bosses which I used as timing marks aren't timing marks. They are probably used in the manufacture of the cams as the holes line up with the lobes.

The timing marks are actually little indents in the outer rim of the bosses on the end of the cams which line up with little nipples on the top of the cam bearing caps on the left of the engine. The left of the engine is gone but the cams still needed to be located in the head so I flipped them over. They now actually rotate backwards compared to original. It's OK as the cam lobes are symmetrical. The problem is that I can't line up the proper timing marks as when the cams are installed originally the lobes will be at a certain angle and the valve stems and tappets are at another angle. With the cams flipped over the lobes are still the same angle but from the cams point of view the vavle angle is now in the other direction. I have to make an allowance of twice the valve inclined angle.

I had to give it up earlier as it was doing my head in. I've found the problem though so it's just a matter of getting it back together properly, and measuring it to make sure. I'll punch a mark in each bearing cap for cam alignment once I have it sorted.

Doesn't say at what lift the measurement is. But i knew i had seen it somewhere.
http://my-x15.net/fzr250/FZR250%20specs.pdf

I have thought i had workshop manual somewhere.But I can only find a 2kr parts manual
Do you have a few left over 3ln front calipers lurking about Mike?

[speedpro]

Pretty sure I do. Their condition is likely to be less than optimal as they are just sitting in a box. You are welcome to them.

You could help me as well. I'm interested in the internals of the airbox, particularly the velocity stack dimensions. The budget is stopping me getting the FI at the moment plus I'm having thoughts about the best options seeing as I want to use FI on the MB engines as well. I've read somewhere the Caltrans system only runs to 12,000rpm on the 2 strokes plus it seems I'd need to buy a completely different system. It makes the Link system a bit more attractive as it could be transferred, plus Neil is using one.

[husaberg]

Pretty sure I do. Their condition is likely to be less than optimal as they are just sitting in a box. You are welcome to them.

You could help me as well. I'm interested in the internals of the airbox, particularly the velocity stack dimensions. The budget is stopping me getting the FI at the moment plus I'm having thoughts about the best options seeing as I want to use FI on the MB engines as well. I've read somewhere the Caltrans system only runs to 12,000rpm on the 2 strokes plus it seems I'd need to buy a completely different system. It makes the Link system a bit more attractive as it could be transferred, plus Neil is using one.

I might have some or at least part of one, There is a couple of boxes full of FZR250 engine bits.I will have a ferret
There is a thread on a CBR250 in Aussie (i think)where some students made there own Fi system.

If i don't have any it might be worth asking on the fzr250 site there is heaps of stuff on there.

But its not this one http://projectcbr250rri.blogspot.co.nz/

i think the one i remember they made the ECU from scratch.

This one i think?
http://feralinjection.com/cbr/cbr2.html


off the FZR the site i think? 3LN
Checked all jets those i could)and are the following:
Main Jets: 1&4 102.5 2&3 100
Jet Needle: all have 5CT7 written near the top.I also dropped the needles to the lowest. That is the little circlip is at the top most slit)
Pilot Air Jets: 105
Pilot Jets: 12.5
Pilot screw as always 3 turns out from full in
Starter jets: 37.5
The emulssion tubes all have N-8 written on the side.


2kr jets
engine idle: 1600rpm
Jet needle: 4DV1
needle clip: 3rd clip from bottom
pilot screw: 3 turns
main nozzle: N-8
pilot jet: #15 (#17.5 for 88-89 w/ exup according to a shop who has access to the genuine parts catalogue, my non exup is #15, so I cannot confirm the size for exup)
main jet: 72.5
starter jet: GS1 17.5 GS2 0.5
float height: 17.5 - 19.5 mm
vacuum: 145mmHG @ 1600rpm
CO: 3.5 - 4.5% @ 1600rpm


When i was going to do one i was going to use a set up off a SRV250 or Viargo as i think it was 2mm smaller and smaller carbs are supposed to be better for blown 4 strokes from what i could make out.( I think they lean out less)

[husaberg]

I had a go through the shed Mike, sorry no bell mouths or air box bit's at all.
2x pretty complete engines (dissembled) 1 seemingly full set of carbs dissembled (odd slide set up plastic ...)
if you need anything just holler.
From the picture they look equal length which is odd, most of the Honda's i have seen run unequal length tubes.

[speedpro]

From observing the standoff when running the bike on the dyno they are way short anyway so probably not any attempt made at tuning but just connecting to the airbox.

[speedpro]

Well in the tradition of tight arsed bucket racers I've dragged an old Haltech E6A "kit" out of the cupboard. I've chopped the loom all up years ago and fitted it to my McIntosh. I just can't bring myself to buy a new Link system. I've already come across a couple of limitations just going through the manual. First is that is is only good for a max of 16,000rpm. I'm pretty sure there will be a way around that, likely by running the triggers all off the camshafts, which is why I extended the end bosses out through seals on the end plate. It's also a bit dated with what it will accept as a trigger and probably will require some sort of conditioner or pulse generator. If using a multi-tooth trigger it is limited to 9000rpm. Reading the manual shows that it has a few nice options, like staged injectors. It only fires one up to a certain load point then fires the first and a second simultaneously thereafter. You can also set the start OR end point of the injection event. You can also fire the injectors in a couple of different modes. I can probably generate the home signal off the camshaft and the actual ignition trigger off the crank for accuracy. It also can't drive ignition coils directly and needs an amplifier. I already have a single channel which the kit came with and a dual channel I bought. I'll need to dummy it up on the bench to see what it's good for.

[Pickle]

Michael let me know what bits you need for the FZR motor as we have numerous motors, frames etc here at work in the wreckers, couple of complete bikes sitting there too. Should be able to get them at good price for you if want

[speedpro]

I'm pretty right at the moment.
We have racing this weekend after which the following weekend I want to see Wobbly to get him look over a few motors. I'll check out his generator system and depending on how it looks might be interested in getting the whole right side generator rotor, stator, and crankcase covers. I've pretty much decided to go for a Caltrons Kawasaki 250 Ninja FI system. The old Haltech system I have is pretty restricted with a low 16,000rpm rev limit and sensor/trigger limitations. I should get a Link Atom ECU but just don't have the money. I checked out Rob's Ecotrons kit in the weekend and it's hard to argue with the value for money and everything is the right size and not built to run a 250+hp car. Plus the throttle body is a near perfect fit on the FZR. On that note it would be a great upgrade for a street FZR. Just use two throttle bodies and double up the injectors. I need to check triggering myself for my project yet but it should be doable.

[speedpro]

Ecotrons Kawasaki 250 Ninja system has been ordered. Turns out the FZR alternator rotor has exactly the same 4 tooth setup as the Kawasaki and it also had a single crank pickup. So I'm fitting a stock FZR alternator back on the motor and just wiring it up to the Ecotrons system. Not looking forward to the wife spotting the VISA card statement. It would seem to make sense as well to make my own engine dyno using some software from OZ. Might wait for things to settle down before doing that.

[speedpro]

The box of goodies arrived a few days after I paid. The throttle bodies are a little rough as expected but are still good value for the price. I'm trying to get my head around the tuning technique. Just reading the manuals at the moment and connecting it up on the bench to the PC. It seems reasonably sophisticated and therefore complex. At lower revs it uses the MAP sensor and revs to determine fuelling and switches to TPS and revs above certain revs and TPS settings at points defined in a table.

I'm on the lookout for a late model FZR250 (3LN model) #4 carb mounting flange. These are short and straight and fit the older (2KR) head like I have used. I tried the 2KR flanges and though the TB fits in the TPS is touching the frame. With the shorter flanges the TPS is well below the frame and I can get the connector on. The 3LN has four unique carb flanges while the 2KR only had left and right. Husaberg is checking for me, but if anyone in Auckland has an older 2KR engine, I am also after the whole generator/trigger/rotor off the right side of the engine. I'm pretty sure I've used a crankshaft from the early engine which has a smaller taper on the end of the crank. I then used the centre from that rotor to fit my degree wheel. The rotor I have has a different taper in it which is bigger. I need the trigger for the ECU and the alternator bits to make power to run the whole lot. Even a stator with a blown winding will be OK as I will probably only use 1 phase anyway depending on load. If I run all 3 phases the regulator will be doing overtime dumping the excess to ground.

[husaberg]

The box of goodies arrived a few days after I paid. The throttle bodies are a little rough as expected but are still good value for the price. I'm trying to get my head around the tuning technique. Just reading the manuals at the moment and connecting it up on the bench to the PC. It seems reasonably sophisticated and therefore complex. At lower revs it uses the MAP sensor and revs to determine fuelling and switches to TPS and revs above certain revs and TPS settings at points defined in a table.

I'm on the lookout for a late model FZR250 (3LN model) #4 carb mounting flange. These are short and straight and fit the older (2KR) head like I have used. I tried the 2KR flanges and though the TB fits in the TPS is touching the frame. With the shorter flanges the TPS is well below the frame and I can get the connector on. The 3LN has four unique carb flanges while the 2KR only had left and right. Husaberg is checking for me, but if anyone in Auckland has an older 2KR engine, I am also after the whole generator/trigger/rotor off the right side of the engine. I'm pretty sure I've used a crankshaft from the early engine which has a smaller taper on the end of the crank. I then used the centre from that rotor to fit my degree wheel. The rotor I have has a different taper in it which is bigger. I need the trigger for the ECU and the alternator bits to make power to run the whole lot. Even a stator with a blown winding will be OK as I will probably only use 1 phase anyway depending on load. If I run all 3 phases the regulator will be doing overtime dumping the excess to ground.

Look no more for the inlet anyway......found all the bits will do the measure thing tomorrow..........the inlet actually say 3ln so i are guessing that's what it is:yes:
The rotor has lKZ01 on it plus 037 000 2110 11 FZ

[speedpro]

Cool. The manifold should also have the number 4 on it. I'm talking about the right most one when looking down the intake ports. I'll compare the rotor to the good one I have that doesn't fit.

[speedpro]

Got the bits from Husaberg. The stator and pickup are all good and I managed to get the end of the broken crankshaft out of the rotor. I now know that Yamaha used at least 3 different crankshafts in their FZR250s. The rotor that Husaberg sent has a taper that is 20mm across the large diameter. The one off the crankshaft in the engine is 21.5mm and the good rotor I have off the other engine's crankshaft is even bigger. Still I can get going with wiring and checking the timing of the trigger teeth on the rotor. Both rotors have the same tooth layout so at least something looks consistent.

So, still looking for a rotor.

[husaberg]

Got the bits from Husaberg. The stator and pickup are all good and I managed to get the end of the broken crankshaft out of the rotor. I now know that Yamaha used at least 3 different crankshafts in their FZR250s. The rotor that Husaberg sent has a taper that is 20mm across the large diameter. The one off the crankshaft in the engine is 21.5mm and the good rotor I have off the other engine's crankshaft is even bigger. Still I can get going with wiring and checking the timing of the trigger teeth on the rotor. Both rotors have the same tooth layout so at least something looks consistent.

So, still looking for a rotor.

Oh well bet the removing the remains of the crank end was fun. did you press it out?
If someone knows what the Puller for the FZR250 also fits let me know and i will check the other one i have.

[speedpro]

Oh well bet the removing the remains of the crank end was fun. did you press it out?

Gave it a squirt of CRC, got it hot with the hot air gun, sat it flat on the vice with the broken stub between the jaws and gave it couple of whacks with an old axle and hammer. The puller thread bit has seen better days.

[husaberg]

Gave it a squirt of CRC, got it hot with the hot air gun, sat it flat on the vice with the broken stub between the jaws and gave it couple of whacks with an old axle and hammer. The puller thread bit has seen better days.

I was guessing the crank end was broken in an off. fracture is jagged to say the least.post a pic
PS. Broken axle.........
<img src="http://www.disney.co.uk/muppets/cms_res/images/download_pics/wallpapers/animal-wallpaper-1600x1200.jpg" width="140px"/>:whistle:

Actually the crankend internal thread had a odd bolt and large assortment of washers on it, as well when i found it.......I took them off before i sent it,buggered if i know why they were on there? Certainly didn't look factory...........

[husaberg]

Look no more for the inlet anyway......found all the bits will do the measure thing tomorrow..........the inlet actually say 3ln so i are guessing that's what it is:yes:
The rotor has lKZ01 on it plus 037 000 2110 11 FZ


Got the bits from Husaberg. The stator and pickup are all good and I managed to get the end of the broken crankshaft out of the rotor. I now know that Yamaha used at least 3 different crankshafts in their FZR250s. The rotor that Husaberg sent has a taper that is 20mm across the large diameter. The one off the crankshaft in the engine is 21.5mm and the good rotor I have off the other engine's crankshaft is even bigger. Still I can get going with wiring and checking the timing of the trigger teeth on the rotor. Both rotors have the same tooth layout so at least something looks consistent.

So, still looking for a rotor.

OK the one still on the engine seems to be marked LKZ23 03700-3060-1YN the inner taper bears the number 51 i never noted what the inner number was on the one i sent you.

[speedpro]

Slowly making progress but still need the correct rotor. I know which rotors it isn't.
037000-2110 11FZ LKZ01 &
037000-2660 2KX LKZ12 aren't the correct ones. If anyone has a FZR250 alternator rotor with different numbers on it I'd like to have a chat.

037000-2110 11FZ LKZ01 looks to have the same inner hub outer dimensions so there could be some swapping of pieces to make a good complete rotor.

[speedpro]

Husaberg, any chance you could have a look at that other rotor. I have the whole bike together and will take it to the track tomorrow for a couple of slow laps. Not willing to take it over 8000rpm or so with the wrong rotor on the crank. As per the Ecotrons thread I've got it running not too bad from cold and blipping it to about 8K. I'm going to give it a run tomorrow, I just can't help myself.

After that I'll start on the exhaust plumbing for the turbo. I'm at a bit of a loss as to how to connect it all. I think it'll need a reservoir built into the exhaust and I was thinking about 1L. The pipes will sweep left to the reservoir then back and up to the turbo sitting where #1&2 cylinders used to be. I already have the water inlet and outlet connections and the oil to the head is via an external pipe with banjo fitting so that is easy. I've fitted a plate to blank off the crankcases so the oil can drain straight down into that. I'm thinking the plenum will need to be about 1L as well. Someone is bound to have experience with this sort of thing and I really welcome advice and suggestions.

[speedpro]

Fitted the regular FZR fuel tank, ran fuel lines, worked all the air bubbles out(I thought) and took the bike to the track for a gentle few laps. Unloaded it and fired it up and immediately thought it sounded flat/off. It sort of petered out and basically that was it. Checked the ECU when I got home and the program load was OK so was pretty sure it must have been a fuel feed problem. I've now jacked up a 4L container with an outlet in the bottom feeding the filter and then the pump. Return fuel tips in the top. Little bit of jiggling round to get the bubbles out and the bloody thing fired up straight away. It may have developed a little problem as it warms up around 40degrees but apart from that it's back to being sharp. I was snapping the throttle to 100% from about 3000rpm and it just picked up real quick.

So, lesson learnt is that it needs a small always-full reservoir to feed the injection pump so there is no chance of bubbles getting into the fuel system.

[husaberg]

Husaberg, any chance you could have a look at that other rotor.
Didn't i send you the Number on it? If ness i can whip it into the bike shop and see if they have the correct puller i guess?
But i are in Wellywood for the next couple of days, so it would likely be next week at the earliest.

[speedpro]

You did send the number. Only problem is that I only know what numbers it isn't. Your one is different so it'd be worth a look at the larger diameter of the taper to see if it matches. Sounds like it might be a bit of a pain for you. Rob's down that way soon though and I'm sure he wouldn't mind bringing a heavy magnetic lump back if you could get it off. Actually I could give him the rotor puller I made years ago for these rotors. It was my first attempt at thread cutting on my rickety old lathe. First attempt at thread cutting ever actually. That way you could remove the rotor at your leisure.

[speedpro]

I've located some new MB100 cylinders, pistons, pins, and clips for US$30/set. Quality unknown at the moment. If anybody is interested PM me and I'll put an order together. Freight is on top so the more the merrier. I need to check the quality but will also look at supplying a kit to make a bit of power - cylinder, head, piston, & pipe if anyone thinks it might be worthwhile. Should see high 20s I'm thinking. Clutches as I'm using in my bike I can already do on an exchange basis.

[speedpro]

Oook! I've got a cost for shipping 10 on top of the unit cost, and expecting GST on top of all that and it comes to about NZ$63/set - cylinder, piston, pin, clips, and gasket. Those still interested should confirm with a PM, and I'll try and catch the missus in a good moment and drop it by her. Sorry if the original US$30 was misleading.

[kel]

Oook! I've got a cost for shipping 10 on top of the unit cost, and expecting GST on top of all that and it comes to about NZ$63/set - cylinder, piston, pin, clips, and gasket. Those still interested should confirm with a PM, and I'll try and catch the missus in a good moment and drop it by her. Sorry if the original US$30 was misleading.

That price is still a total bargin. Don't suppose they can supply a couple KE125 cylinders?

[speedpro]

Pretty sure they would, I'll check. You need to buy 300 as a minimum but at $1 each it isn't really a problem. The same place also does MB crankshafts. I'm thinking of getting some. I'll let F5 be the first to test one as he is fond of Chinese conrods.

[F5 Dave]

I'm not even keen on Chinese food:angry:

[husaberg]

I'm not even keen on Chinese food:angry:

They just call it food.........


Pretty sure they would, I'll check. You need to buy 300 as a minimum but at $1 each it isn't really a problem. The same place also does MB crankshafts. I'm thinking of getting some. I'll let F5 be the first to test one as he is fond of Chinese conrods.
it would be worth it just for the crankwheels....... i was thinking of asking you about them but i thought it would be too cheeky

[F5 Dave]

They just call it food.........

Yes, but I'm not 'They'


I'm part of 'We'.

And We' call it Chinese food.

And its not often very nice. Now the Thais, the Thais know how to cook. Heck even the Malaysians beat the Chinese hands down in the food stakes.

When your national cusine is considerably worse than the Mexicans, who rely heavily on Beans, Rice & flatbreads, then you know that you're a bit sad. People think of Mexicans as lazy, but it isn't a good stereotype esp when the Mexican woman is concerned as their food preperation is quite labour intensive.

Indian food can be spectacular. But its Mexi tonight & now you've made me hungry.

And a little thirsty. but I'll have to go all crosscultural on the beer

but I am going to the supermarket. . .hmm.

[husaberg]

Yes, but I'm not 'They'


I'm part of 'We'.

And We' call it Chinese food.

And its not often very nice. Now the Thais, the Thais know how to cook. Heck even the Malaysians beat the Chinese hands down in the food stakes.

When your national cusine is considerably worse than the Mexicans, who rely heavily on Beans, Rice & flatbreads, then you know that you're a bit sad. People think of Mexicans as lazy, but it isn't a good stereotype esp when the Mexican woman is concerned as their food preperation is quite labour intensive.

Indian food can be spectacular. But its Mexi tonight & now you've made me hungry.

And a little thirsty. but I'll have to go all crosscultural on the beer

but I am going to the supermarket. . .hmm.

That's a lot of gross generations there. BTW ya missed insulting the French, Swiss,Greeks and Italians.;)
The Chinese (well the ones that can afford a decent diet) wouldn't even serve it to their Dogs....... Oh sorry that's more Korean isn't it.

I am so Hungary i could eat a Belgian.......
Sorry to waffle on a bit..

[Bert]

Pretty sure they would, I'll check. You need to buy 300 as a minimum but at $1 each it isn't really a problem. The same place also does MB crankshafts. I'm thinking of getting some. I'll let F5 be the first to test one as he is fond of Chinese conrods.

Try some rmx50 (hummm I mean RG50) barrels as well.
I was exchanging emails with on company that would send a sample of 50 units, try your luck....

[kel]

Try some rmx50 (hummm I mean RG50) barrels as well.

The RMX and SMX are totally bucket legal, dirty big T port and all. I'm at a complete loss as to why the aftermarket kit cylinders aren't fitted to every rg50. Yeah I know :Offtopic:

[speedpro]

Finally got the FZR125 on the track. Took it to Mt Welly, unloaded, started it and warmed it up - all good. Put leathers on, "tried" to start it again with no luck. Found out how unfit I am - really really unfit. Finally just for something to do checked the battery, it was a bit low but fell over when the pump powered up going down to 7v or so. Fitted the other battery and away it went. Managed to get in a few laps revving it only to about 8-10,000rpm and it seemed OK(ish). After a reasonable number of laps it started trying to idle higher and higher finally revving to 10,000rpm. I suspect the battery voltage has sagged out on the 2nd battery causing the fuel pump to struggle making it run lean and fast. So another lesson learned - I need to sort out the generator and electrical system. Good thing is the new fuel surge tank works a treat. I only had to toggle the pump on/off three times and it was all purged and ready to go. One happy camper at the moment. Now just need the correct rotor and I can give it the revs.

I'm probably about 1/2 way to getting the turbo on it, at which time it will magically become a 100. I thought making a 2-stroke chamber was difficult to make nice but the turbo exhaust isn't far behind. Should look pretty cool when finished though nobody will know as it'll be wrapped.

[husaberg]

Mike Send ya Puller down
I will send it back with the other rotor..........
Still think that Aisin AMR300 you have would be a better bet for the 100cc F4 though.

[Pickle]

[QUOTE=speedpro;1130612046]Finally got the FZR125 on the track. Took it to Mt Welly, unloaded, started it and warmed it up - all good. Put leathers on, "tried" to start it again with no luck. Found out how unfit I am - really really unfit. ]

HaHa I seem to remember pushing one of your bikes for quite a long time before you noticed something was turned off - still owe me for that

[speedpro]

I've also just sorted a possible order for 10 MB100 crankshafts, tacked onto the end of a mass order. Cost + shipping + GST totals about NZ$50each. PM me if you are interested. The main order is due for completion in 15 days evidently so need a reply soonish.

[speedpro]

After I got the bike home I started it up and after a few seconds warming up it climbed to 5000rpm where the fuel cutout activated dropping the revs and so it cycled up and down. So I was right, more air was getting in, through the throttle body. When I took it out on the track initially it was all good but then the idle started creeping up to the point where it wanted to rev quite high. The fuel wasn't cutting out over 5000rpm with the throttle closed which should have been a clue. At home however after turning it off & on the 0% throttle position was reset so the fuel cutout worked. I checked over the throttle body with the engine running and found I could push one throttle closed which lowered revs. Further checking found the idle screw was loose. So I screwed it out until the idle was at the programmed 2000rpm and the ignition advance auto adjusted to the desired angle for the rpm with no correction to try and adjust the idle. With the idle too high it backs off the ignition advance to try and lower the rpm. This causes problems with response as it doesn't seem to advance super quickly when you crack the throttle. With the TB idle screw adjusted properly the ignition is advanced a bit and the initial throttle response is good.

I've hooked up the regulator with the generator and battery. It helps but it looks like I also have a problem with the generator output - it's pretty weak. The winding resistances are different so a bit of a clue.

[speedpro]

Mike Send ya Puller down
I will send it back with the other rotor..........

I just noticed on the rotors I have that there are two threads. The later model rotor with the taper which is too big has a thread pitch of probably 1.5mm. The rotor I want, and the rotor with too small a taper, has a fine pitch thread, probably only 1mm. A quick check of what's on the motor will tell you if it's even worth taking off.

I've actually been thinking of making a small cone from 1.5mm sheet and fitting the big taper rotor. Correct rotor is preferred choice though.

[husaberg]

I just noticed on the rotors I have that there are two threads. The later model rotor with the taper which is too big has a thread pitch of probably 1.5mm. The rotor I want, and the rotor with too small a taper, has a fine pitch thread, probably only 1mm. A quick check of what's on the motor will tell you if it's even worth taking off.

I've actually been thinking of making a small cone from 1.5mm sheet and fitting the big taper rotor. Correct rotor is preferred choice though.

Mmmm.i can take a pic and you can compare i guess?

Later ok looked at it it looks coarse to me. The outer thread that is.
I guess you want 2KR pretty sure both of the motors i have are 3LN.

[speedpro]

Tenant's left our rental 2 weeks ago after 6 years. New paint, new kitchen cabinets, paint and tools and crap filling my garage to the point where you can't get to the other side. Only got the oven door to fix so it closes that is taking up a bit of space on the bench and we'll be back to normal. Anyone looking for a 3 bedroom house with garage, carport, and storage in Massey feel free to PM me. Had a look at the turbo plumbing for the first time in over 2 weeks and Gaz rang for a bit of a chat tonight. Starting to feel normal again. Well, until I looked at the VISA account anyway.

The guy who bought the Yamaha FZR bits in Hamilton lives out this way and I'll be dropping by shortly to check if he has a rotor that will do the job. He listed a FZR bottom end with a rotor but unsure if it's what I want.

[speedpro]

Found a different rotor and hoping like hell it's "the one". I couldn't get it off the crankshaft so had to buy the whole bottom end. Will bring it home tomorrow and go to work on it.

[F5 Dave]

In for a penny.

[speedpro]

Rotor removed with much effort, but without flames, and safely installed on the motor. I've fired it up in the back yard and it revs good though it hesitates real bad at 7-9,000rpm with 1/2 throttle. Once over 10,000rpm it blips sharply and sounds pretty good. I haven't been too hard on it but it seems to cut at 16,000rpm which is the highest value able to be defined in the tables for the ECU. Hopefully I'll be able to put it on the dyno soon and give it a proper test. I asked specifically about the rpm limit before I purchased the system so will be hopping if it's a problem.

[speedpro]

Some minor progress with the turbo plumbing. The turbo doesn't quite sit right but easily fixed as one more weld to go. Need to start on the intake plenum. I'm not really sure what I'm doing with this but figured a plenum was needed to smooth out exhaust pulses but mainly to even up the back pressure on each cylinder. The intake will have a similar problem but fluctuating pressure. The cylinders have matching intake and exhaust cycles separated by 180 crank degrees and then a big pause before the next cycle.

[speedpro]

from on top

[Grumph]

Personally I'd doubt if you need a plenum on the exhaust - i thought the idea was to keep velocity up in the system before the turbo ?

On the other end, when i did the blown 500 kawa twin I used a plenum on the inlet around 1600cc volume. That worked well and gave us even mixture distribution. 180 deg twin - is yours 180 or the center two cylinders of a four - ie 360 deg ?

[husaberg]

For the inlet ........The guy that does the Ducati turbos in the states once said that 3.5 time total cylinder capacity is a good rule of thumb for a twin.If that helps.
One other thing i have noted is that on the 3 cylinder turbo manifolds at least one of the cylinders always seemed to direct straight at the turbo, pretty sure the log manifolds on the twin turbo skylines did the same. No idea why though.

[speedpro]

The engine is cylinder 3&4 so it's a 180deg twin. I've thought about the exhaust plenum and would have kept it compact if it was a 4 or a 360deg twin. With the odd firing intervals it seemed like the exhaust pulses would meet quite different manifold pressure depending on which one was first or second, hence the plenum. The 2nd cylinder would exhaust into the cylinder after the first meeting more resistance to gas flow and then on the other side would suffer reduced intake pressure after #1 had done it's thing. Being injected the fuel distribution should be sweet. I know what you mean about the difficulty of fuel distribution in an intake manifold of a suck through carbed turbo system. Z1Rs would run #2 a bit lean and that was always the first cylinder to have problems. There's some comment from a few "names" in the exhaust and turbo world and they all say the same - just get the gas to the turbo in the shortest simplest way. Blake enterprises did turbo kits for Z1s years ago with a real ugly log style exhaust manifold with no apparent harm. Spaghetti style systems are for looks and style. My McIntosh has very short headers into a small dia pipe which connects to the turbo behind the engine and that works great. My turbo Cefiro had a pretty ugly exhaust manifold as well but went pretty good.

[ac3_snow]

... My turbo Cefiro had a pretty ugly exhaust manifold as well but went pretty good.

Bloody hooligan

[Grumph]

I should have phrased it differently - the plenum gave us equality of cylinder filling...I'd been a tad worried about the first cylinder to open the inlet taking all the boost to the cost of the second cylinder.

I understand what you're saying re the pipe. If results don't match expectations it's easy enough to delete the plenum...
Another possible avenue to look at is simply different length primaries - a bit of creative pipe bending and you've got different lengths/volumes in the headers.

[speedpro]

Moving right along, intake plenum progress. It's taken longer than I thought but each little runner is tapered and has a hand beaten bell mouth. That's how it goes with only tin snips and a hammer or three. I've got to be careful not to do something that will stop me cleaning it up once finished. I don't want to risk crap getting into the engine. The connection to the turbo will be a cone on the end of this to a short pipe and then a piece of hose bent to the turbo where it will connect to another pipe on a flange.

[F5 Dave]

Have you considered a 2 stroke? I hear they go quite well. No wasted cycle.

[speedpro]

bit more progress. The intake plenum is finished with help from Darren. He helped set me up with his TIG welder, his flash welding helmet(I want one) and I purge welded the end cap on with an awesome result. Got the little flange for the turbo to intake hose and have a good idea now for the exhaust plenum end cap. Talking to Darren about how to close off the intake plenum and he says to use a dome and then fishes a SS dome of the exact right diameter out of a box of bits. Of course spent more time talking shit than working at Darren's workshop but constructive as always.

[Grumph]

bit more progress. The intake plenum is finished with help from Darren. He helped set me up with his TIG welder, his flash welding helmet(I want one) and I purge welded the end cap on with an awesome result. Got the little flange for the turbo to intake hose and have a good idea now for the exhaust plenum end cap. Talking to Darren about how to close off the intake plenum and he says to use a dome and then fishes a SS dome of the exact right diameter out of a box of bits. Of course spent more time talking shit than working at Darren's workshop but constructive as always.

Are you putting an explosion valve anywhere on that plenum ? In my experience with 180 twins, and wasted spark ignition, it happens more than you'd like. From memory, first 3 goes at getting the blown kawa running we had to reset the explosion valve each time...winding up the spring preload each time till it would accept the odd spit back happliy. that was on meth though...and pretty rich too.

[F5 Dave]

Pike river Plenum?

[husaberg]

Pike river Plenum?

the elsberg tuning site with the supercharged 50 has a good pic.

[speedpro]

Sequential injection and ignition. It uses the MAP sensor pulses to determine which cylinder is where on the cycle and only fires that ignition.

On the dyno today there was no blowback at all at any rpm. Pretty disappointing though. For some reason it isn't tipping in the fuel it should as you open the throttle. The injector pulse width increases but only slightly and the motor sticks at say 8,000rpm. Sometimes it will catch and rev up to 16,000rpm or so. You can see into the throttle bodies when they are wide open and it isn't until the PW jumps up and you see the fuel fog jump up that the motor takes off. The TPS monitor indicates the TB opens and closes as you move the throttle but it doesn't add fuel like it should. Injector PW seems to stick at say 3.4mS whatever you do with the throttle. Almost like it's only monitoring the MAP sensor and not the TPS.

I'm familiar with supercharger blowoff panels. The "doorslammer" guys used them. Sometimes they'd completely fold them back hard against the frame of the panel. Silly bastards would double the panels if the motor popped one or two. The next thing it popped was the supercharger or the manifold.

[speedpro]

Finally made a bit more progress. Been learning a bit, mainly things not to do, like running the surge tank low on fuel and then not bleeding the air out. That took a night or two to figure out. Anyway, have now got it where it starts reliably on the stand just by spinning the rear wheel in 3rd. I've upped the rpm where it considers "start" to be over and the motor running from 780rpm to 1,200rpm. I also added fuel to the "Start Fuel factor", "After start factor" and the "Warm-up factor". It wasn't too hard to figure once I got a handle on which table was being used when. Once I got it idling and warm so no additional factors were affecting the fuel injected I then started adding fuel to the VE table, increasing the values from about the centre of the table up, in a single block from values of about .8-.9 up to a single value of 1.5 across the whole range. The improvement has been immediate and obvious. Whereas it didn't blip cleanly, now it sounds real sharp. So far I'm only using small throttle openings so even with the higher revs it is still using the VE table rather than the TPS table. I'll need to load it up to sort that properly. As per my crossover table at the higher revs with anything more than about 10% throttle it will switch to the TPS table. It's tempting to modify the switchover table to just use the TPS table at anything over say 5,000rpm at "any" throttle position, just to make it simple to figure which value is relevant at any load/rpm.

Pretty happy though. It starts easy, idles sweet, and throttle response so far is good.

[TZ350]

Good going Speedpro.

[husaberg]

For the inlet ........The guy that does the Ducati turbos in the states once said that 3.5 time total cylinder capacity is a good rule of thumb for a twin.If that helps.
One other thing i have noted is that on the 3 cylinder turbo manifolds at least one of the cylinders always seemed to direct straight at the turbo, pretty sure the log manifolds on the twin turbo skylines did the same. No idea why though.


Good going Speedpro.

It occurred to me Mazda must know how to do 2 cylinder turbos.
Note the turbo inlet directly op one cylinder the 3 cylinder and twin turbo skylines do the same.:drool:
Its a sexy wee bit of Technology i had forgotten about.
Gave me another idea too....
http://www.rx7club.com/2nd-generation-specific-1986-1992-17/s4-vs-s5-turbo-exhaust-manifold-921791/

i can't post pics from there but visit it. Twin Scroll it Mazda Mitzi and Subaru all have done it.
http://www.rx7club.com/attachments/2nd-generation-specific-1986-1992-17/403027d1284262912-s4-vs-s5-turbo-exhaust-manifold-3659-jpg

[speedpro]

The default config had the engine as a 62.5cc engine. I asked about it and was told that was correct. Yesterday I got an email casting doubt on that. So, I set the engine capacity to 125cc and reloaded the default VE and TPS maps. Double the cylinder capacity would result in twice the fuel requirements being calculated. On John's dyno it ran rich enough after start to have both cylinders blowing flames out the pipes. Easy enough to fix by simply setting the warmup enrichment to "0" at 30degC. After warmup it seemed rich at lower throttle settings at lower revs so I set a small block to smaller values in the VE table. The engine was sounding pretty good so I decided to put it in gear and give it a rev. That worked good enough to try a full throttle "through-the-gears" run. It revs better than the video sounds but limits at 16,000rpm. Pretty happy for sure. Will start tuning on my holidays.

http://youtu.be/x0quPqr3wkE

[mr bucketracer]

sound neat ! i want one ..sounds like a 60s racer

[speedpro]

JC's neighbours must love seeing the Legnum turn up. I've had a few afternoon sessions on the dyno. I still have to get the dyno software fully sorted but I can record runs and do comparisons. Today I was just looking at 10% throttle runs and only up to about 8-10,000rpm. With this throttle opening the ECU refers to the Volumetric Efficiency(VE) table and never the TPS. With the throttle held as steady as possible there are only a small range of values ever active through the rev range so it is pretty easy to make adjustment and rerun the test.

What I've been doing before starting the engine is make changes to the VE table in the region I'll be testing, save it on the PC and send it to the ECU. Then I've made the next changes to the saved copy of the VE table ready to import to the active table. I then fire the bike up and do the test after which I import the modified VE table and run the next test. A quick comparison says if the tuning was going in the right direction. A new set of values can be entered as a block and then the table re-imported and the next run done. It's quicker than it's taking to type this.

Anyway, as good as I thought the engine sounded it turns out it has been a bit rich. Decreasing the values has netted 1hp or a whopping 50% increase. Even with no load at 10% throttle the motor will only rev to 10,000rpm and when you look down the throttle bodies you can see that there is very little opening for air to get in.

Without a dyno PC there is still a way of checking how well the engine is accelerating. You can record lots of things during a session using the software that comes with the ECU. By looking at the engine speed and the rate it increases you can see if the power tails off. With a bit of mucking round you can see which values would have been in use in the table and make a change. A Lambda sensor would make it even easier.

[speedpro]

Had another session today. It definitely needs the Throttle bodies adjusted for synchronisation and to then balance the idle air screws and I'll sort that tomorrow. Today I decided to try to save the dyno runs and then recall them for analysis and comparison. Finally managed it and ended up doing some 30% throttle runs. At 30% if the engine is revving over 4000rpm it uses the TPS/RPM table. Holding the throttle steady results in the same line of values being used so it's pretty easy to tune. Initially it just sort of faded at about 10,000rpm. I altered the whole row of values it was using to the same larger value and did another run. There was a gain across the whole rev range and it revved to 11-12,000rpm. I increased the values and reran the test and got another gain across the whole range and now it revved over 14,000rpm before fading. The last test, I increased all the values again and it revved on quite nicely and was sounding crisp. Towards the end I thought my leg felt warm. I was standing beside the bike, reaching over to the throttle and running the PCs with my other hand, and not really watching the bike itself. I had a blanking plug in a hose that will eventually feed water to the turbo. This popped out and released hot water all over the dyno, and my leg.

Back at home I've made a piece to clamp to the twist grip. This will allow the throttle to be opened to more or less the exact same position every run. This will reduce errors and speed up testing. It's difficult to hold the throttle steady enough if the bike is bouncing around a bit. I'll go back tomorrow with a bag of T-pieces and small hoses and hook up my vacuum gauges to sort out the TBs and then finish testing.

[speedpro]

More time on the dyno and a very important reminder of how the tables work. The dyno does not record engine rpm so I wanted to match 10,000rpm to a particular speed. To do this I set the TPS/RPM table value at 10,000rpm and 32% throttle to about 1/2 what seemed a good value, as tested. The next run should have seen it fall flat on it's face at 10,000rpm. What actually happened was not much. It ran through the load cell as if nothing happened. I then set the values at 10,000rpm for the TPS settings above and below 32% to the same value and did the run again. This time it ran into a wall at 10,000rpm.

This was a good reminder that the software does not read the value "only" at the highlighted cell but blends the values in the cells around to determine the correct fuel requirement. It was interesting to see the fuel pulse width slowly decrease as the load cell with the seriously reduced value was approached.

So all the effort so far has just been tossed. That is because I have only been altering the one row for 32% throttle. The rows above and below are markedly different. I copied the values from the 32% row to the rows above and below and the engine would not run at 32% throttle. I have to think of a new tuning strategy. I'm thinking of concentrating on a particular cell, say 32% TPS at 10,000rpm, and altering all adjacent cells to the exact same value initially and testing until I have the optimum value then picking another cell and so on. Once I have a few cells mapped I can blend the intermediate cells after which it would need to be done again. It's going to be a mission.

To end the session #1 cylinder exhaust has broken off, just great. 2nd beer just finished, bbq to sort, low/mid 20s, gentle breeze, more beer, 1.5 weeks more holiday, to the beach tomorrow. Sweeeeet!

Oh yeah, I haven't got sick of the sound this thing makes.

[speedpro]

Bit of shed time and I've added a piece of tubing at the end of the headers. It is purely there as a place to mount the O2 sensor. It's pretty ugly but does the job. Before he went to Chch John Connor lent me a wideband O2 sensor kit he'd made for a 600. I've fitted that sensor with it's own little control box with series of LEDs indicating rich/lean.

After I warmed the engine up in my garage I could see the LEDs indicating the mixture fluctuating as I revved the bike. At idle it was indicating rich so I took .1 out of the VE table around the active cell and it immediately responded by indicating a bit leaner. I took a bit more fuel out and the indication was leaner and leaner and the idle went up, to the point where the ignition backed off to reduce the engine torque and therefore the idle speed. The ignition backing off made the indication go rich so I got in and reduced the idle air bypass on the TBs. This normally would reduce the idle speed but in this case the ignition timing advanced again, the indicated mixture returned to normal, and the idle stayed the same. I had loaded the default VE table and pretty well knew it was a bit rich but this confirmed it.

I'll use this WB sensor on the dyno to get things in the ballpark and then mount the Ecotrons NB sensor and log the results which I'll then use to tune the engine a bit more precisely.

I thought it interesting that the mixture indicated so rich when the timing retarded to lower the idle RPM. It could be a trap as you could keep taking fuel out until it got so lean the engine slowed down and then the ignition would advance again as the idle reduced and the indication would go more lean, and back you go the other way. You definitely need to adjust the TB stops or idle air bypass to set the idle without the ignition retarding. It's only a problem on TBs with no idle air stepper motor.

[speedpro]

Just got a pile of new software from Ecotrons. They were a bit shy with the truth when I ordered the system. I specifically asked about the system supporting the engine doing 18,000rpm and the reply was positive. Turned out I could only specify up to a maximum of 16,000rpm. After running the engine on the dyno it turns out it will only rev to 14,000rpm which is a software limitation. They have sent new software which allows 16,000rpm. I've run a comparison but there was nothing of interest found. I suppose they get a lot of silly enquiries and just thought my question was another one not expecting their answer to ever get tested.

I have also received an update on the problem when the ECU case was bolted to ground and it stopped working. Rob has had the same problem. Turns out it was a manufacturing fault which is easily fixed by popping the lid on the ECU and inserting a bit of insulation.

I've got new software to run the ECU so will have to flash that which looks pretty easy with the supplied "flash GUI" software.

They also supplied an updated ".cal" file with the auto-learning feature enabled. I sent them my last ".cal" file and they included all my modified tables in the new file. I could have imported all the tables one at a time but that would be a bit of a pain so a nice touch them doing it.

I also got directed to a new tuning guide which looks to have a lot more detail which will be of interest to anyone doing something a bit different. Still slightly odd English in places.

Their ALM device is looking better and better. It uses the higher spec Bosch sensor and has a very fast response time. It also includes an input for rpm. This is connected to an injector. Although most WB controllers have a programmable 0-5V output which could be used by the ECU some are considerably slower responding and therefore not as good for tuning. As usual nowadays it's the software that makes the difference. The ALM as well as connecting in a reasonably straight forward manner also comes with software that allows the output to be captured via a serial port/USB and displayed on a graph of rpm versus lambda which could be useful.

[koba]

You and TZ have kept me keen on Carbs!

[speedpro]

Funnily enough I've been quietly reminiscing about a lovely set of brand new Keihin CR31s I bought in 1982.

I've also thought it would be interesting to install an O2 sensor on a carb'd bike and map the lambda at a range of throttle positions and rpm settings. I suspect things won't be that flash as a rule. Of course for racing it doesn't really matter about part throttle so much, certainly emissions are of no concern and even being a bit down on power at a particular throttle/rpm combo, you just open the throttle a little more.

My setup is running pretty sweet at the moment and there is plenty more to be done. It's just that you can identify exactly how well the engine is running at a huge number of load points while with a carb you don't have the huge range of precise adjustments to make. A carb can be made to work very very well though in the real world. Emissions are what has driven the engine management/fuel injection transformation primarily in the real world I think

[Grumph]

Funnily enough I've been quietly reminiscing about a lovely set of brand new Keihin CR31s I bought in 1982.

I've also thought it would be interesting to install an O2 sensor on a carb'd bike and map the lambda at a range of throttle positions and rpm settings. I suspect things won't be that flash as a rule. Of course for racing it doesn't really matter about part throttle so much, certainly emissions are of no concern and even being a bit down on power at a particular throttle/rpm combo, you just open the throttle a little more.

My setup is running pretty sweet at the moment and there is plenty more to be done. It's just that you can identify exactly how well the engine is running at a huge number of load points while with a carb you don't have the huge range of precise adjustments to make. A carb can be made to work very very well though in the real world. Emissions are what has driven the engine management/fuel injection transformation primarily in the real world I think

Emissions and the sheer difficulty of an owner tampering with it.....Legislators hate tamperers.....

Back when we had a Superbike round, Anders Andersson raised eyebrows with an O2 sensor on his OW01 Yam....he said it made changing to suit local conditions faster.

Personally it's taken me around 40 years to get to the level of knowledge I have now around carb setup....I don't have long enough left to learn injection tricks.

[speedpro]

On a completely different tack, I have been messing with Gary's MB100 engine. Finally put it on the dyno after work with nice improvements from the test done earlier. I had to up the jets a couple of sizes and backed the timing off a bit. The power is modest but it'll be easy to use. The needle may have to go down one notch but we'll check that on the track.

[goose8]

On a completely different tack, I have been messing with Gary's MB100 engine. Finally put it on the dyno after work with nice improvements from the test done earlier. I had to up the jets a couple of sizes and backed the timing off a bit. The power is modest but it'll be easy to use. The needle may have to go down one notch but we'll check that on the track.
Big thank you to Mike the bike was awesome to ride today , time to give it a big blow out tomorrow and go for some wins

[F5 Dave]

. . .time to give it a big blow out tonight and go for some wins[/QUOTE]

Fixed it for you.

Yeah that's my usual training too. Less on the vodka these days. More a nice bottle of wine. Or so.

[Pumba]

Fixed it for you.

Yeah that's my usual training too. Less on the vodka these days. More a nice bottle of wine. Or so.

And in bed by 8.30pm if the away meets are to go by

[Henk]

And in bed by 8.30pm if the away meets are to go by

Not that he stays with us anyway, prima Donna factory riders that want real beds and stuff.

[koba]

On a completely different tack, I have been messing with Gary's MB100 engine. Finally put it on the dyno after work with nice improvements from the test done earlier. I had to up the jets a couple of sizes and backed the timing off a bit. The power is modest but it'll be easy to use. The needle may have to go down one notch but we'll check that on the track.

What would you put the power range at in revs?

[speedpro]

8-11K at a guess. It seems low revving and flat. Peak is a whisker under 20rwhp so lots less than expected. There's a couple of things I didn't check before assembly and the pipe though good, had a similar effect on the motor previously where it seemed flat. We'll run it on the dyno and try a few pipes I have lying around including a copy of my 30hp pipe. Wobbly has a new pipe designed specifically for this motor setup so will have to ask nicely for him to send it.

[speedpro]

Also . . . I managed a few laps on the FZR 125/2 today. It actually wasn't too bad. As I knew from dyno runs it won't rev out as the small injectors just don't have time to inject the fuel over 15K rpm. Plus it's way overgeared and I only used 1st & 2nd. If I could run it out to 18K I'd only need 1st. I had the turbo inlet plenum manifold fitted to reduce the risk of something going down the intake and it didn't seem to adversely effect it on the dyno and no problems on the track. The throttle is a pain needing over 1/2 turn for full throttle. The engine is pretty weak but runs sweet with only a little burble here and there. On and off the throttle it behaved very well with no stuttering or hesitating. I'm very happy with how it ran and am even more convinced now that fuel injection is the way ahead.

[koba]

8-11K at a guess. It seems low revving and flat. Peak is a whisker under 20rwhp so lots less than expected. There's a couple of things I didn't check before assembly and the pipe though good, had a similar effect on the motor previously where it seemed flat. We'll run it on the dyno and try a few pipes I have lying around including a copy of my 30hp pipe. Wobbly has a new pipe designed specifically for this motor setup so will have to ask nicely for him to send it.

Would be good to get an extra thousand over-rev...

I'm now convinced that power/power-range balance is far more important than the total horsepower number, for kart tracks at least.

[goose8]

. . .time to give it a big blow out tonight and go for some wins

Fixed it for you.

Yeah that's my usual training too. Less on the vodka these days. More a nice bottle of wine. Or so.[/QUOTE]

Well the ten beers last night might of been just what I needed got seven wins an a second bike was great all day .

[koba]

Fixed it for you.

Yeah that's my usual training too. Less on the vodka these days. More a nice bottle of wine. Or so.

Well the ten beers last night might of been just what I needed got seven wins an a second bike was great all day .[/QUOTE]

Hmm, that's a good idea, taking it easy and only hitting ten beers the night before a race day.

[speedpro]

Tried Gary's other pipe on the bike tonight. A quick measure showed it was short by 30-50mm so I wasn't expecting much. The graph compares the best of the runs made with the pipe I made for a different specification motor. That pipe is 30mm too long but worked OK even if the power is down. The short pipe evidently has small sections missing, 1 or 2, which were left out by the person who welded it together.
You can see the graph has a surge after peak which will be the pipe. I had to jet it down 2 sizes and advance the ignition about 5deg to get this curve. It clearly was never going to match the first curve. It is a very good example of mismatched tuning of parts.

[speedpro]

I hate that

[speedpro]

More stuff to hate. Has to be the worst I've managed so far. It even leaked gearbox oil.

[Skunk]

Looks like your avatar. What, where, when.


If it ain't smokin' - it's broken.

[cotswold]

Is there anything left to salvage, can't remember seeing such wholesale carnage before.

(hope you don't mind but I've shared a couple of your pics on a different forum, they are so horrid they need a wider audience )

[speedpro]

Looks like your avatar. What, where, when.


If it ain't smokin' - it's broken.

Max revs on the dyno, top gear, just shut it off. It made a funny noise and I grabbed for the clutch but it went "clack" before I got my hand to it. Something had gone off since before the last meeting and it was a couple of horse down. I had tried a few things inbetween times and was just checking settings to see if it was that. Evidently not. Spread the collection of MB and H bottom ends out in the garage, decided which cylinder we'll use and should have the new motor together tonight, or I might get in and do some mods first. Pretty sure which mod caused this so won't be trying that again.

[F5 Dave]

That plug will never be the same again. Cheap insurance, I'd suggest replacing that.

[speedpro]

New plug(just for Dave) new bottom end, old H100 cylinder, old pipe. Making essentially the same power as before but not as nice and wide. We tried the good pipe hanging out the side and the broad power came back but with a dip between two peaks. The dip is about 1.5hp and the peaks are similar values. It isn't a surprise as this cylinder is different to the MB that the pipe was built for. I widened the ex port 2mm each side and raised it about 2.5mm. The transfers have the specified timing but the T/A has to be way down as they are otherwise stock. The angles are all wrong as well but I'll devcon them next week to sort that out. I was going for blowdown T/A with the ex port being 70% of bore diameter, across the chord. All the increase in ex port size is above the transfer port top edge height. The ex port duct has been left at the original small size. The port itself has been enlarged but tapers down over about 15mm to the original size duct. The outlet of the duct is too large so without machining and installing an insert it was the only option for a reduced ex duct. I need to talk to Wobbly to see if cutting steps in the alloy inside the duct will work, instead of having a small duct extending right out to the pipe, with the flat top and bottom of the duct forming steps into the round pipe. It looks OK on the dyno especially with the good pipe but is peaky with the old one. Just need to fill Gaz with coffee and sugar and we should be good.

Cricket will have to put a bit more effort into getting the right gears out of corners though he is getting pretty good at hammering the clutch.

[speedpro]

Well I finally brought myself to butcher the best pipe I've ever made. Now it fits the H100. Gary owes me for emotional stress big time. Before and after pics below. I had to justify it by considering what could be done prior to the GP for best effect and the pipe wins by a mile. A couple of runs on the dyno on Friday to confirm jetting and it'll be all good.

[koba]

Well I finally brought myself to butcher the best pipe I've ever made. Now it fits the H100. Gary owes me for emotional stress big time. Before and after pics below. I had to justify it by considering what could be done prior to the GP for best effect and the pipe wins by a mile. A couple of runs on the dyno on Friday to confirm jetting and it'll be all good.

Shoelaces are untied...

[speedpro]

Yamaha Sport Vid cam from my brother. Cool kit including 2 batteries, number of different mounts, motion detection, a remote control, and a whole load of other stuff. Check the specs.

[koba]

Looks decent!

[quallman1234]

Cool! Those ones have always looked like they maybe rebranded GoPro's / slightly changed for yamaha. So should be really good! Good score!

[Pickle]

Yamaha Sport Vid cam from my brother. Cool kit including 2 batteries, number of different mounts, motion detection, a remote control, and a whole load of other stuff. Check the specs.

Just remember it's for your son!!!!

Hope he enjoys it, Cheers

[speedpro]

I thought about who it was for after I posted and thought it might be taken as me being a bit possessive.

Anyway, been to the dyno again, just checking a few things. The bike is a bit sad with the big ding in the bottom of the pipe after the shock mounting bolt broke. I dragged up a few other runs for comparison

Run1 black is Gary's bike with Dave's H100 cylinder and the fat pipe.
Run2 blue is Gary's MB100 engine with the fat pipe.
Run3 red is my MB100 with the flattened pipe
Run 5 purple is my motor with the fat pipe.

Run 1 is interesting with the double hump, obviously a mismatch there which is no surprise
Run 2 is a pretty good match for a JCR CB150T but the whole bike weighed 20-30Kg less.
Run 5 without tuning anything would make an awesome kart track engine with a huge fat curve.

My good engine has a problem with 6th gear which is odd as with the gearing and the revs it does 6th is never used. It kept jumping in and out of gear on the dyno.

I'm about to put Dave's motor back together with a modified ex port and nothing else. If Gary is OK with it we'll fit the fat pipe. Then I can use my shortstroke bottom end and play with the three 52mm cylinders and try different pipes. I have a new pipe which is still to be assembled but as it is designed specifically for the port layout that was in Gary's MB100 before I blew it up I'm expecting to get a few more hp, plus I never did get the porting finished so fingers crossed.

[koba]

I thought about who it was for after I posted and thought it might be taken as me being a bit possessive.

Anyway, been to the dyno again, just checking a few things. The bike is a bit sad with the big ding in the bottom of the pipe after the shock mounting bolt broke. I dragged up a few other runs for comparison

Run1 black is Gary's bike with Dave's H100 cylinder and the fat pipe.
Run2 blue is Gary's MB100 engine with the fat pipe.
Run3 red is my MB100 with the flattened pipe
Run 5 purple is my motor with the fat pipe.

Run 1 is interesting with the double hump, obviously a mismatch there which is no surprise
Run 2 is a pretty good match for a JCR CB150T but the whole bike weighed 20-30Kg less.
Run 5 without tuning anything would make an awesome kart track engine with a huge fat curve.

My good engine has a problem with 6th gear which is odd as with the gearing and the revs it does 6th is never used. It kept jumping in and out of gear on the dyno.

I'm about to put Dave's motor back together with a modified ex port and nothing else. If Gary is OK with it we'll fit the fat pipe. Then I can use my shortstroke bottom end and play with the three 52mm cylinders and try different pipes. I have a new pipe which is still to be assembled but as it is designed specifically for the port layout that was in Gary's MB100 before I blew it up I'm expecting to get a few more hp, plus I never did get the porting finished so fingers crossed.

What happened to 30 hp?

[jasonu]

What happened to 30 hp?

Beat me to it... Different bike is my guess.

[mr bucketracer]

Beat me to it... Different bike is my guess.i think just a low reading dyno. useing as a tuning device rather than worrying about max hp readings .. well thats my guess

[speedpro]

It was less than 30hp after the last rebuild. I used the same size piston as the original which in conjunction with wear in the bore made it a little bit looser than optimal. Plus there may have been a bit more hp missing for other reasons. That graph was also with the the pipe after it had been flattened. I'll be yanking the motor out and having a look at it this weekend. If I'm feeling wealthy I might fit a new piston and ring, along with a new 6th gear. Dave and Gary have been making the engines look a lot better than they actually have been, though Gary's motor had a monster spread of power. The dyno does read low but only about 15%.

[F5 Dave]

Monster spread? How can you tell without revs? Or just compared to another engine you do know?

[speedpro]

Two MB engines are built. Dave's H100 is back in his bike with small mods to the exhaust. Bit of work yet and we need to get him enthused again after a difficult season on the 600. The MB in Gary's bike is my short stroke bottom end and my old MB cylinder and his ignition. Time was of the essence so nothing is machined. I've measured the other 2 52mm cylinders and know what I need to do but need time. Gary was working on it today so hopefully we'll be able to run it up next weekend.

I've also been busy fitting the WB lambda sensor from Ecotrons to the FZR. I've also fitted the 128g injectors. I took out all the start fuel enrichment but had to add a bit to get it started and then it was off and running with a few tweaks. I tried the autotune function but without a brake to hold it at steady revs and load I could only work the very low throttle settings. I manually tuned a few other sectors of the maps and you could easily see the gauge step up and down and the digital readout alter. I've wired up the rpm input to an injector wire so can record lambda versus rpm using the software provided. It works pretty good but that bit is only really useful for the TPS MAP as the VE map steps around with revs with no adjustment in throttle so you never really know which cell was being used at any time unless you are actually looking. I have to try and split the screen so I can see what's happening with the lambda at which cell in the VE table. I'll also need to get 2 RS232-USB adaptors working at the same time for inputs from the ECU and the ALM lambda sensor. A quick play this arvo had it sounding crisp with the lambda hanging round .8+. It still doesn't like going over 16,000 and there's a few things I need to check. I thought it still leaned off a bit up high but need to check further.

If anyone in Auckland has a brake dyno or even just a brake I could use I could get into the autotuning properly. I don't need to measure the power it's making, the only thing I'm interested in is the mixture which I can read off the gauge and the PC.

[Moooools]

If anyone in Auckland has a brake dyno or even just a brake I could use I could get into the autotuning properly. I don't need to measure the power it's making, the only thing I'm interested in is the mixture which I can read off the gauge and the PC.

We have one at the workshop. It is 1960s era and made for a car, but was chopped down and rewelded to stop guys putting their cars on it. So still quite wide for a bike but that doesn't really affect steady state. The biggest problem is that it currently has no front wheel cradle for a bike.

I would probably use it as a last resort but if you get stuck I can check that the others are okay with it and you can whip up a bit of steel to hold the bike in place and bolt it on. Also a few guys around who have played the fuel injection game before who would be keen to check out the project/ offer advise.

[speedpro]

Hell yes. I'd be keen to drag the bike over for a measure and then glue something together at my mate Darren's workshop. He may even be interested in running his bike on it as well, if he ever stops pissing round with those horrible carb things. PM me the details of where you are and I'll try and jack up a time.

I went and collected the small amount of date I saved from Sunday. It looks like the injector pulsewidth is still topping out at about 7.5ms at about 15,000rpm and the indicators are that it isn't rich. Pretty good graphs show it is leanish through lower revs. Easy to fix if into the TPS map, not so easy to identify where the problem is if at part throttle in the VE map.

[TZ350]

It looks like the injector pulsewidth is still topping out at about 7.5ms at about 15,000rpm and the indicators are that it isn't rich. Pretty good graphs show it is leanish through lower revs.

4 stroke at 15,000 rpm / 2 = 7,500 firing cycles per min.
7,500 / 60 = 125 cycles per sec.
1/125 = 0.008 or 8mS

At 15,000 rpm with 720 degrees between firing events it takes 8ms per cycle.

If you allowed 0.5ms in the Ecotrons advanced calibration settings (min close time) for the injector to close then at 7.5ms pulse width your injectors have topped out.

Yes, it looks like you need even bigger injectors to be able to run above 15,000 rpm.

[koba]

So, Speedpro, I have the engine out of your old sidecar...

I don't know if it is still the one you built or if it has been re-done.

I remember you said you had an electric water pump, this one has a mechanical one driven from the ignition side of the crank.

I think I will start a new thread actually...

I have a lot of questions, might as well spit some out now...

Reedblock was a standard MB one with the centre web hacked out and a big carbon reed, yeah?

What pistons did you run?

Did you run no balance shaft and no rebalance of the crank?

[speedpro]

Reed block sounds like the one I altered. I used standard MB pistons which were good as gold running up to 14,000rpm regularly. The big fat ring tips were another matter and a few went missing. I used an electric water pump and a vacuum pulse fuel pump from a small outboard motor. I left the balance shaft in and did not rebalance the crank in that engine. The only engine I've rebalanced is my good (ex)30hp motor with the balance shaft removed. I also ran a CR80 ignition and a 28mm Keihin carb.

[wildman]

So, Speedpro, I have the engine out of your old sidecar...

I don't know if it is still the one you built or if it has been re-done.

I remember you said you had an electric water pump, this one has a mechanical one driven from the ignition side of the crank.

I think I will start a new thread actually...

I have a lot of questions, might as well spit some out now...

Reedblock was a standard MB one with the centre web hacked out and a big carbon reed, yeah?

What pistons did you run?

Did you run no balance shaft and no rebalance of the crank?

Hey Koba, when i picked up the sidecar from Graeme Kidd in Lower Hut he said the engine had another barrell on it as the original was destroyed and it now runs an RM watercooled piston but he couldn't remember what model and the water pump is a modified RM one as well. The person you got the engine from should of had the carb for it as well.I think the stator plate on ignition is cr but not sure what model and the cdi unit was a bit oddball but Econo Honda thought he had located one in Australia, Hope that helps.

[F5 Dave]

Skidd redid the barrel. If you ever need to find him he has a workshop behind Mac.

[cotswold]

Reed block sounds like the one I altered. I used standard MB pistons which were good as gold running up to 14,000rpm regularly. The big fat ring tips were another matter and a few went missing. I used an electric water pump and a vacuum pulse fuel pump from a small outboard motor. I left the balance shaft in and did not rebalance the crank in that engine. The only engine I've rebalanced is my good (ex)30hp motor with the balance shaft removed. I also ran a CR80 ignition and a 28mm Keihin carb.

I've still got the reed block and the carb, you can have the one but not the other. The block is the 1st one. The PWK28 has been re-furbished and lives on my 50. (when it gets finished)

[koba]

I've still got the reed block and the carb, you can have the one but not the other. The block is the 1st one. The PWK28 has been re-furbished and lives on my 50. (when it gets finished)

Cheers Guys!

I have a carb and reedblock, just wanted to see what the others look like, cheers for the pic!

The Piston in there is a nice bit of kit, good thin rings and 54.5 mm.

Going to try it on my roadbike, 115 is a bit over the top for running in buckets!

Plus the liner is getting really thin!

I guess with an offset pin set to stroke It I may be able to make just under 125...

[Henk]

I've still got the reed block and the carb, you can have the one but not the other. The block is the 1st one. The PWK28 has been re-furbished and lives on my 50. (when it gets finished)

Bring it to buckets this weekend if you want to get it to Wellington and I'll drag it down next week.

[koba]

Bring it to buckets this weekend if you want to get it to Wellington and I'll drag it down next week.

No need, I have one modified to replicate sitting on the desk right next to me!

[speedpro]

Been busy putting a new pipe together for Gary's MB. I've been grinding the welds inside with the Dremel tool, just where I've used a bit of filler rod and it's made a bump. After that I've used a flapwheel to clean it down properly. This has got me wondering if there is a finish that is better or worse on the inside of a chamber. A lightly ground finish might be good for creating a boundary layer. My thoughts were that it probably would not be a benefit with actual gas flow but that it might have some beneficial effects with the boundary layer acting as an insulator which might help the exhaust gas temperature jump back up after the throttle is reopened, rather than the pipe busily sucking heat out of the gas. Has anyone experimented with this?

[Grumph]

Been busy putting a new pipe together for Gary's MB. I've been grinding the welds inside with the Dremel tool, just where I've used a bit of filler rod and it's made a bump. After that I've used a flapwheel to clean it down properly. This has got me wondering if there is a finish that is better or worse on the inside of a chamber. A lightly ground finish might be good for creating a boundary layer. My thoughts were that it probably would not be a benefit with actual gas flow but that it might have some beneficial effects with the boundary layer acting as an insulator which might help the exhaust gas temperature jump back up after the throttle is reopened, rather than the pipe busily sucking heat out of the gas. Has anyone experimented with this?

Sounds worth asking on the ESE thread.
Smokey Yunick used to recommend cleaning out stock exhaust manifolds with an abrasive slurry used in pipeline cleaning. He also used it on race headers too to put the sort of finish on you describe. Never seen the results quantified though...personally I'd get the chamber sandblasted thoroughly. There are still some outfits around actually using sand as a medium.

[speedpro]

Pipe finished at about 10pm night before raceday. Took it to the track without starting it and then ran it all day with only one quick look at the plug. We'll check it properly next week on the dyno. It's a bit rough but I was a bit short of time as usual.

Gary and Cricket both managed a first place and between them managed to toss it away 3 times. Luckily the weather held off and it was a good days bucket racing. We had a new slick for the front and a fresher 600 front on the rear. We also had a new front wet but that will be tested some other day

[speedpro]

A short video of the start of the first race for B grade

http://youtu.be/dbswh_SKjzw

[koba]

Bugger!!!!

[Buddha#81]

shite bloody motard pitbike thingamegig's fault!!!!! how dare he mess up a perfectly good race? :eek:

[speedpro]

Finally got back on the dyno with the FZR. The 2 month break must have done me good as straight away I have the Lambda reading reasonably good over the full range of throttle and revs, up to 16,000rpm anyway. I've added fuel to the start and warmup phase but it does go a bit rich on warmup as it warms up before the warmup phase is finished(you need to read that bit slowly). Ideally I need to change the slope of enrichment versus engine temp. I've also set it to more or less only use the VE table which works off the MAP sensor. Theoretically it should have problems at large throttle and revs but it seemed OK. The reason is that I can't see how it will work with boost using the TPS table as the throttle position will have little relevance to airflow with the turbo. I may have to change another table which defines the relevance of each table in the final calculation of fuel amount to be injected.
The new 128g injectors seem OK. I have to add fuel at start and warmup so they aren't TOO big, and at high load they are on for about 5mS out of an available time of about 7.5mS, at 16,000rpm.

As usual with time off, I'm busy with other more important stuff, like working on the house.

[speedpro]

Got a bit of time in the shed. Collected a few MB bits, machined a head for squish and compression, and set the port open/close angles. Opened the exhaust port up but left the duct more or less the same size from 15mm in right to the pipe flange. First run on the dyno saw 20hp and after 5 runs had 23.5hp. The piston is a bit loose so a new one is going in. I also set the squish .1mm tighter than I normally do and there is just the barest evidence of the piston tapping the head so depending on time I'll either remachine the head or just shim the cylinder up .1mm.

23hp in Gary's bike which weighs more or less 70Kg, with Cricket on it, should be fun at Tokoroa.

I'm gonna freshen up my old MB cylinder and my 30hp cylinder so will have plenty of options.

Had the FZR on the track at the last meeting. Apart from being ridiculously overgeared it wasn't too bad. The motor ran faultlessly. Getting off the line at the start was a bit of a mission. With the gearing I didn't really need to change up and used 1st gear everywhere except towards the end of the straight. Running it out to 16,000rpm it was sweet. No real horsepower with the intake manifold/plenum which is made to be fed by the turbo. The cams are also timed for forced induction which I suspect is not helping.

[koba]

Got a bit of time in the shed. Collected a few MB bits, machined a head for squish and compression, and set the port open/close angles. Opened the exhaust port up but left the duct more or less the same size from 15mm in right to the pipe flange. First run on the dyno saw 20hp and after 5 runs had 23.5hp. The piston is a bit loose so a new one is going in. I also set the squish .1mm tighter than I normally do and there is just the barest evidence of the piston tapping the head so depending on time I'll either remachine the head or just shim the cylinder up .1mm.

23hp in Gary's bike which weighs more or less 70Kg, with Cricket on it, should be fun at Tokoroa.

I'm gonna freshen up my old MB cylinder and my 30hp cylinder so will have plenty of options.

Had the FZR on the track at the last meeting. Apart from being ridiculously overgeared it wasn't too bad. The motor ran faultlessly. Getting off the line at the start was a bit of a mission. With the gearing I didn't really need to change up and used 1st gear everywhere except towards the end of the straight. Running it out to 16,000rpm it was sweet. No real horsepower with the intake manifold/plenum which is made to be fed by the turbo. The cams are also timed for forced induction which I suspect is not helping.

First gear all the way, Woah!

I've left the duct standard size on mine, I'll probably continue to do so given that post.
Can I ask what kind of reed setup you have on the 23hp job?
I'm part way through a VERY short inlet with a standard block and the big single reed, it's planned as just an interim step though.

[speedpro]

The reed is of unknown origin but a substantial 6 petal type similar to the one in my 30hp cylinder. It's pretty basic with no splitter and no proper insert to transition from the carb flange to the petals. The only attempt at a transition is short extensions of the rubber carb flange into the reed block. The transfer ports are completely untouched except at the very entry to the ducts where someone has taken them out quite a bit giving the ducts a pronounced taper.
The exhaust port from about 15mm down from the piston face is untouched as far as I can tell. At the pipe flange it is slightly oval with a pronounced lip at the top, probably about 5mm at the centre. The port at the piston face is 70%ish chord width and has a shape that gives the most blowdown, though it is still deficient in that area.
On my old MB sidecar engine I used the standard reed block but cut the centre divider out and fitted a single fibre petal. That motor made a nice 19.9hp and it had major design flaws. The reed block definitely will benefit from careful shaping of the transition from carb flange to reeds. A few I've played with sounded noticeably different on the dyno and the engines were a lot cleaner at part throttle and transitioning on and off throttle.
With the reeds, because we want to rev the engines high the reeds need to be short because we want the resonant frequency to be above the operating frequency. When the reed stop is flattened out it leaves a shorter reed available to open reducing the cross-section of the reed block port. To regain the cross section required the reed block needs to be wide, hence the 6 petal reeds being used. As supplied though they are normally too long and once the free reed length is reduced it is back down towards the ideal reed cross-section.

[koba]

The reed is of unknown origin but a substantial 6 petal type similar to the one in my 30hp cylinder. It's pretty basic with no splitter and no proper insert to transition from the carb flange to the petals. The only attempt at a transition is short extensions of the rubber carb flange into the reed block. The transfer ports are completely untouched except at the very entry to the ducts where someone has taken them out quite a bit giving the ducts a pronounced taper.
The exhaust port from about 15mm down from the piston face is untouched as far as I can tell. At the pipe flange it is slightly oval with a pronounced lip at the top, probably about 5mm at the centre. The port at the piston face is 70%ish chord width and has a shape that gives the most blowdown, though it is still deficient in that area.
On my old MB sidecar engine I used the standard reed block but cut the centre divider out and fitted a single fibre petal. That motor made a nice 19.9hp and it had major design flaws. The reed block definitely will benefit from careful shaping of the transition from carb flange to reeds. A few I've played with sounded noticeably different on the dyno and the engines were a lot cleaner at part throttle and transitioning on and off throttle.
With the reeds, because we want to rev the engines high the reeds need to be short because we want the resonant frequency to be above the operating frequency. When the reed stop is flattened out it leaves a shorter reed available to open reducing the cross-section of the reed block port. To regain the cross section required the reed block needs to be wide, hence the 6 petal reeds being used. As supplied though they are normally too long and once the free reed length is reduced it is back down towards the ideal reed cross-section.

Cool, I'll have to stew on that for a bit!
I've actually been mocking all this reed stuff up on your old sidecar engine!

I've also notice the 'feel' from good inlet shaping/stuffing, it's something that is ver difficult to quantify but give a definite advantage.
It's actually a big factor in that cheaterbike argument.

[speedpro]

With a fresh KT100 piston in my short stroke bottom end with my old cylinder and head the motor seems sweet. However at the last meeting as soon as Dave gave it a bit of throttle on the track it seized. I cleaned it up but it still wasn't looking perfect so had a hone run through it just for looks and to check it was straight and true. Then fitted a new piston the same size, 52.15mm. Ran OK in the driveway during a couple of heat cycles. The kart mechanic was definite about the motor having an air leak causing it to seize so I filled the sink and dropped the motor in with 5psi pressurising it. It seemed completely airtight. Today though Dave had a repeat where it seized as soon as he went a bit hard. He'd already done a couple of good sessions where he wasn't going too slow. I haven't had it on the dyno so the tuning is a complete unknown but it runs OK and sounded OK. The plug looks good being a bit dark if anything though the inside of the header has an ever so slight hint of grey to it where typically it is light tan.

Going back to kart mechanic guy's assertion of an air leak, and looking at the pipe and mounting flange, I can see where the air/fuel charge is going to the end of the flange and slightly into the pipe and then hopefully being jammed back into the cylinder. The pipe is a reasonable fit on the flange and I assembled it with a bit of high-temp red silastic, but I wonder if that is where the air leak might be. That plug of fuel and air in the port/flange/pipe might be diluted by an airleak and be returned to the cylinder lean causing the piston to seize.

Gary's new motor is going good. I have the exhaust and transfers heights set to work with a good pipe and it has a nice intake which I've fitted my 34mm carb to. I was hoping for a bit more hp but ended up with more or less the same hp as before the freshen up, 23.5 and nice and fat. Considering the transfer ports are untouched at the cylinder I'm reasonably happy. I've found a guy who knows what he's doing who has the tiny tools needed to alter the transfers so that's next on the list after fixing Dave's bike.

You never know but I might even do a bit more work on my FZR125 over Christmas.

[F5 Dave]

Yeah mine seized twice at Ruapuna on closed throttle. I'd run out of time to leak test it but when I do find problems it is usually the intake. Bigger pilot fixed the issue for that meeting. You might just be lean there.

[speedpro]

I find it hard to believe being a bit lean at closed throttle could cause a siezure. However I am going to try a bigger pilot jet or if I can't locate a suitable size jet I'll drill one out and if I can't find one I don't mind driling I'll try a known good carb.

I'm going to test that out using the last piston which I've resurrected using a piece of 80 grit W&D paper on a piece of glass under a running tap in the sink. It's come out "looking" pretty good but as for size I don't know. The kart mechanic suggested a technique where you wipe the smeared face of the piston over the W&D with a turning/curling motion so the whole face gets sanded with each wipe.

[F5 Dave]

Mate, most seizures seem to happen on a closed throttle, lots of revs, not much gas, then you could open the throttle when it was about to nip & go super lean for a millisecond.

At Ruapuna mine seized twice going into the hairpin totally closed for some time and locked the (light under braking wheel). That's why KTM were adding an injector to richen closed throttle.

[speedpro]

Got a range of pilot jets, fitted the biggest and worked down until it was good. It seemed best with a 45, from the standard 40, but when I stripped the motor again there was ever so slight scuffs. We've settled on a 50 jet and it seems good. We ended up using that engine in Dave's bike in the races on Sunday and Cricket set a new personal best of 31.5 once he got clear and Gaz was going round and round OK as well, apart from one lap, but we won't mention that lap. Clearly the seizures were caused by going lean on the pilot jet. After sanding the piston and reassembling the motor I dynoed it at 22.7hp. Being the lazy type that I am I didn't even bother adjusting the ignition to try for a bit more. That was Dave's bike with essentially my old air cooled engine.

Gary's bike was going good on Saturday and early on Sun. We'd dynoed it at 23.5hp using Lance Morgan's old MB engine I rebuilt and made some changes to. The transfer ports at the cylinder are completely untouched so reasonably happy with that. On Sunday when Cricket was riding it there was a little problem - see photos. Most likely pre-ignition with some detonation thrown in for good measure. The plug ceramic has gone as has the earth electrode. Easily fixed, though the head won't ever be as nice without being fully machined which at the moment isn't going to happen. I've just very carefully dressed it up with the Dremel.

309110309111309112309113309114

[koba]

Got a range of pilot jets, fitted the biggest and worked down until it was good. It seemed best with a 45, from the standard 40, but when I stripped the motor again there was ever so slight scuffs. We've settled on a 50 jet and it seems good. We ended up using that engine in Dave's bike in the races on Sunday and Cricket set a new personal best of 31.5 once he got clear and Gaz was going round and round OK as well, apart from one lap, but we won't mention that lap. Clearly the seizures were caused by going lean on the pilot jet. After sanding the piston and reassembling the motor I dynoed it at 22.7hp. Being the lazy type that I am I didn't even bother adjusting the ignition to try for a bit more. That was Dave's bike with essentially my old air cooled engine.

Gary's bike was going good on Saturday and early on Sun. We'd dynoed it at 23.5hp using Lance Morgan's old MB engine I rebuilt and made some changes to. The transfer ports at the cylinder are completely untouched so reasonably happy with that. On Sunday when Cricket was riding it there was a little problem - see photos. Most likely pre-ignition with some detonation thrown in for good measure. The plug ceramic has gone as has the earth electrode. Easily fixed, though the head won't ever be as nice without being fully machined which at the moment isn't going to happen. I've just very carefully dressed it up with the Dremel.

309110309111309112309113309114

What piston is that?

[speedpro]

What piston is that?

KSI KT100. I've got some genuine Yamaha pistons and a single Burris. You have to be careful with squish angles and stuff when swapping brands.

[speedpro]

Funny flow lines in the combustion chamber. I don't recall seeing that sort of thing before. Any ideas? I wonder if it's something to do with the preignition.

[speedpro]

Finally got the cylinder back late this arvo. Had to sandpaper the piston to fit as the mechanic had left it tight due to the piston being 2nd hand plus it had nipped up previously. I don't know how it works but it measured bigger than it's original size. I've done it before and it worked fine using #120 on a glass plate under a running tap. It ended up with more taper than a standard new piston and just a whisker tight at the bottom of the skirt. The squish is on the limit and I'm expecting the piston to just touch the head, but only just. Will fit it tomorrow night, throw it in the van, and go to Edgecombe Sat morning.
Got nylon all over Dave's bike, not that he'll need it. Just have to keep Gary off it.

[koba]

Finally got the cylinder back late this arvo. Had to sandpaper the piston to fit as the mechanic had left it tight due to the piston being 2nd hand plus it had nipped up previously. I don't know how it works but it measured bigger than it's original size. I've done it before and it worked fine using #120 on a glass plate under a running tap. It ended up with more taper than a standard new piston and just a whisker tight at the bottom of the skirt. The squish is on the limit and I'm expecting the piston to just touch the head, but only just. Will fit it tomorrow night, throw it in the van, and go to Edgecombe Sat morning.
Got nylon all over Dave's bike, not that he'll need it. Just have to keep Gary off it.

Goody!

Can't wait!

[speedpro]

Got home today and Gaz had it assembled, tested and loaded in the van. Evidently it rattles a bit, strange that.

Dave, Gaz, and Blair are heading down tonight. Me and Cricket will go down tomorrow morning.