Will I get my 100 ready in time for Taupo?

[F5 Dave]

Well I've made some highly complex cardboard templates for mounts. I'll cut them out of plate & draft Sully to glue them together I think.

Koba came around last night & we pointed at bike bits & dribbled on a little sucking beers, but ended up bouncing off some better ideas for getting the mounts in plane + a new top mount idea that will achieve a variable head height set up with just some easily replaceable steel plates.

Best tool; good ideas. Thanks mate.

[F5 Dave]

Honda's controlled frame flex theorem was advanced to its logical conclusion.


ok so the front & back are sorted, just the middle to do now.

[Bren_chch]

haha awesome, will ride like joe now!

go look at my thread, there is a question for you... :yes: lol

[husaberg]

Honda's controlled frame flex theorem was advanced to its logical conclusion.


ok so the front & back are sorted, just the middle to do now.

Maybe you should have stayed with the cardboard maybe needs some ductape:bye:

[F5 Dave]

haha awesome, will ride like joe now!

go look at my thread, there is a question for you... :yes: lol
Don't have paasword at home to answer, will look a gain at work, but answer is RS ign will have to be set to a pos that suits your engine, its trial & error.

[Henk]

Smear some epoxy on that string and you'll be all good.

[jasonu]

Maybe you should have stayed with the cardboard maybe needs some ductape:bye:

But cardboard goes soggy if it rains.:facepalm:

[husaberg]

But cardboard goes soggy if it rains.:facepalm:

And Dave doesn't?
I would suggest wrapping both in Glad-wrap, but i guess it's not that kind of forum:innocent:

[Bren_chch]

Don't have paasword at home to answer, will look a gain at work, but answer is RS ign will have to be set to a pos that suits your engine, its trial & error.

thats kinda what i figured... cheers ears!

did u make them pics u sent me blurry and small on purpose...? what i can see looks good.

[F5 Dave]

well that was the default setting windows suggested for web. i have some higher def ones I'll send on if I remember, but the beer is kicking in now & it would be rude not to have a wine or so with dinner. Spanish chicken stuffed with choritzio, lemon, cherry tomatoes & a heap of other things. Yum.:wings:

[Bren_chch]

mmm yum... yeah get in to the wine so ur in practice for when u get down here!!!

[F5 Dave]

I'm always in practice, that's the problem.

[Bren_chch]

i like ur commitment!!

[F5 Dave]

Sheesh this has been hard work getting everything to line up. These frames are meant for RS125s & not much else.

Sully came around & tacked up the plates I made & we had drilled some holes, but I'm having to twist the engine on the rubber mounts to get it to line up. I'll measure the hole position to teh SW & rear wheel pivots. No slight on Craig's work, things are going to move when you weld them so far from the frame without a jig, But I made the holes anyway.

Put the transmission shaft back in so can do line up pretty soon. & make the spacers to suit. Will be nice to have a engine in the frame.

I've made a new manifold & will rebore the barrel & work out final amounts to take off top or bottom. 5 weeks to next Kaitoke meet which will be my only test before BOB. Will have to remain air cooled for that.

[koba]

Will have to remain air cooled for that.

Could be bloody snow cooled at this rate... :cold:

[F5 Dave]

Well we've made some decent progress. Engine in frame & steel head stay plates made (last drill hole once barrel skimmed to correct height. Have done some more Devconing cases & some more grinding to lessen the inlet restriction between the crank & lower gasket surface. Reedblock flowed & I'm quite happy with that.

Engine bored. I've devconed in a new rear wall of ally to replace where the crank extended the boost port straight down. The ally is curved a bit & just clears the bore so it won't pick up on the piston even with a tiny allowable bore.

Crank is the only sticking point. I need it to do final checks before skimming barrel top & bottom & reshaping head for new piston.

I'll try take a pic or two, but I'm a bit lazy with that sort of thing. I had hoped to get it for a shake down run on the 19th so I didn't go to the BOB as first run. That may not be possible. but it may just if the planets align. I may have to take a gamble & skim on calculations & adjust later.
Pipe needs last bit too.

Thanks Sully for welding. Its all come together quite nicely.

[F5 Dave]

Its running to the wire. Certainly no time to get it near a dyno & touch & go for this sunday. Sat taken up watching the kiddies (can't trust them in the garage, one is 3 & the other just walking). So its up to late nights to get it together.

Barrel is being checked for square base surface, I can't measure it properly or trust my lathe to skim it as there isn't much left to hold onto. Supposed to get that today. As the crank I am to get today if all goes well.

Craig has finished the header pipe which has been gusseted or strengthened or whatever you'd call it, but its an A1 job, the man's skills are increasing all the time. I'd given him some plated steel originally & apparently that makes it more crack prone, so next time I'll get some plain mild steel. Pity as I have heaps left.

So I have to put the engine together & see it agrees with my calculated port timings & adjust with gaskets & skim the head so it pokes in the barrel a bit. Just too scared to do it before I get all the bits for a final measure as putting metal on again is hard.


So will my bike be ready for Kaitoke?

[crazy man]

yes you will have it ready just a nights work you will have it together but that is a piss poor pic you have there

[F5 Dave]

yeah a lot of things have to fall in line, weakest link & all that could trip it up. If I don't get the crank tonight I'm stuffed. Pretty much I have tonight & tomorrow night & I can't start till 8. I have to hope everything drops into place.

I faced the spark plug hole last night so machining it should be less hit & miss using a s.plug mandrel.

Pic is pretty crap yeah, just blazed a few off & this one hid the messy welding & grinding of the down spars that was done for the 125 motor & adapted to the last motor. So she ain't a pretty bike. Lets hope it makes up for it with some speed.

[F5 Dave]

Well crank & barrel back in my possession.
So progress last night (after helping clearing up a child vomiting minutes after I put her in bed).

Engine all new bearings fitted.
G'box & crank loaded & engine screwed together

Degree'd engine & cut new gaskets to bring it to where I wanted, worked out well.
Skimmed head to adjust squish. Coming on midnight, can I be bothered measuring the Comm. I have skimmed a bit off & piston is more domed, supposed I'd better.

Measured compression. . . opps waay too high.
Cut, measure, hmm close enough.

Pull it apart & clean out the plasticine in the boost port (long story) & apply some more JB weld to the back of the repaired piece in the port.

ok its reached my self (ok wife) imposed 1am deadline. Off to bed.

The only really concerning part apart from all the little things that need to be adjusted on the way, was that the crank didn't slip into place freely. We'd polished the bearing surface, but clearly not enough so had to do up the cases to pull it together. But it wasn't rotating freely. Gave it a bit of a tap which is common practise if the bearing is tight & that helped, but its not fantastic. A bunch of power can be burned up there.

It could be the home made gasket (std no longer fits) might be encroaching a little & rubbing on the webs. If so that will self-correct once the bike fires up & all will be good. Its turning a lot better after several rotations, so it may have to be suck it & see. Hopefully I haven't knocked it out of alignment winding the cases up. I'll know when I start it (or that I've got the balance factor wrong).

Pretty much tonight to put it back together, do a leakdown test, fit the clutch side & ign, fit it to the bike,, connect all the ancillaries, pipe etc, fit bodywork & ready to fire up.

[speedpro]

I know the pressure is on Dave but stop and take a breath and think about the fit of the crank.

Are you happy with it, really?

I've sometimes had a motor that didn't go together just right but after running a hot air gun over the cases and getting them good and hot it must have let something ease into place and everything freed up, could be worth a shot. I always warm the cases prior to assembly which lets the bearings slide right on in.

After attenpting to tru up a crank myself and seeing how easy it is to move them around I'm a big fan of having it all slip together easily.

[F5 Dave]

Thanks Mike I'll try that. I had warmed the cases & put the bearings in with the press so all was going well. The RH side was polished enough so it slipped in, but the left I'm surprised about, maybe the donor fit bearing was looser through wear. I'll give the cases a good dose of heat.

Several times last night I considered slinking off to my bed. Admit defeat, too hard, not enough time. Things that needed a tickle to fit properly. Did I really need to do a leak down test? can't be bothered. . . .oh all right. Sss Nothing. Oh yeah, forgot the exp plug. Try again. Sssssssss gone. Hmm, oh here's a welding hole & there's a hairline crack at the back of the barrel where the rod had smacked it & opened up a weak area around the old reedblock. Bit of Devcon & that should all be ok. Two more leaks at the reedvalve. Red RTV & that should be sorted.

Slowly the bike made its way together. More things like throttle cable & fuel line are a bit short as carb lower down/ further back. Bit of a reroute & should be ok at least for Kaitoke.

1 o'clock rolled around & there's just the headstay plates (taken off 5 times to drill the holes & trim top which was hitting tank) to go back on. It sparks, needs some gas & I'll prop the heater under the cases where the crank area is quite exposed & give it some heat for a while. + the head bearing race that I need to pick up at lunchtime.

Glad I pressed on as wife is sick so I'll have no time till sunday. Bit tired now though.

[Kendog]

Impressive efforts I must say.

[F5 Dave]

Well its been a few late nights, but I left the heater going under it for 1/2 hr till it was toasty & turned the gas on & pushed it up the drive. Let clutch out Bawa, Reached for the choke cable & it started right up. Sounds good. Tomorrow will tell.

So it was ready for Kaitoke. Van loaded, taking my 50 in case & 'cause I like riding it.

[crazy man]

Well its been a few late nights, but I left the heater going under it for 1/2 hr till it was toasty & turned the gas on & pushed it up the drive. Let clutch out Bawa, Reached for the choke cable & it started right up. Sounds good. Tomorrow will tell.

So it was ready for Kaitoke. Van loaded, taking my 50 in case & 'cause I like riding it.well done old chap

[F5 Dave]

Well a fairly ignominious start. Bit cold blooded, didn't want to idle. Gentle practise laps, didn't like off closed throttle. Pilot must be too small now. Decide to keep away from that range if I can & will change. Lap 2 it feels like it nips when I have the clutch in changing gear, so i don't let it out.

back in the pits, engine rotates fine, plug & top of piston look fine. Wonder if it did seize? Pilot jet is possibly blocked, but change 30 to a 50 to be safe. Needle from leanest clip to mid & go from a 300 to a 310mj.

Starts up easy as. Warms up well & idles. Lap 2 Siezes. Apart & the ring is not smeared but there is ally on the bore.

Clean up best I can but after an hour of sanding (in between racing the 50) I can still only get the piston to go up & down in its normal position. If I rotate the piston 15* it is sticky. The bore should be round so orientation shouldn't matter. Clearly it is not round. So I got the bore done last week, but I had also ground a little of the spigots. perhaps that relieved the stresses & it took a new set.

So I can't say if the seizure caused the issue & it was just a little lean (ign had been retarded from where I used to run it & the piston top looked new + the ring didn't smear over so its not real excessive heat). -Or that it was not round & was a bit doomed as soon as it got some real running heat in it. But that seems most likely.

Still better than this happening in the SI BOB. Apart from that it ran ok it not imediatelty super powerful (I wasn't thrashing it of course) & it was on initial retarded settings. Didn't vibrate unduely so the crank appears to be fine.

Given the barrel to the local Kart tuning chap who has all the measuring gear to check for roundness & is well versed in torque plates on anything that gets hot, so I should have an answer soon + he can rehone it straight.

[F5 Dave]

Well I'm wrong again. Bore is straight & true. Piston is picked up in a funny manner. I have another one arriving but in decent light we could see & actually feel how there were ridges. I've mill-filled & sanded them out so it drops in cylinder in any position, perhaps they were just dropping into the ports instead of sliding past them.

I've re leak tested & I did find my reedblock that was salvaged from the 350 had been re-drilled to suit & the elongated holes created a path up the bolt holes, + there was some more damage from the conrod creating a passageway through a crack that had not been fully devconed so I've redone that.

[jasonu]

Hey Dave maybe if you spent more time actually doing stuff to your bike instead of jacking off on KB you might just finish it.
Also any chance of me and the missus dossing on your couch sometime next Feb? I'll supply the beer.

[F5 Dave]

I seem to be getting out of the garage the following day I went in too many times.

Feb? Yeah should be no drama:cool:.

[F5 Dave]

Bah. Sometimes they just are hard to shake the numbers out of. I was reasoning a 1mm bore increase & a slight destroke & port timing to the same numbers should not have that much effect. Same pipe, same ign & same carb.

Fit to cases that don't leak & have a reedblock that is the same width as the cases (the last one was ~5mm wider but had to taper in & was an issue of reeds hitting sides) + aim is now straight shot, not smack into the crank. + the manifold is a straight shot instead of 20 degrees.

It just has to be better. Maybe a couple of HP better I'd have thought.

So why am I 6hp down on previous? Things that have changed: Destroke, bore. Piston is pretty similar to the YZ one I was running. I also cranked the comm up from a very conservative 14:1 to 15:1. The timing & mainjet is right on what they were previously so I'm not making up for too high comm. I spent a lot of time & ended up back where I started with these settings.

Where is my 6, or more hp hiding? if it were reeds totally unable to keep up you'd hear them & the power curve doesn't flatline like fluttering reeds, infact it pulls nicely to 13 & the curve has the same shape & humps as the previous engine at the same revs, which is hardly surprising. Rules out the slipping clutch too.

I'm thinking internal friction on the crank.

[Bert]

Bah. .....

Where is my 6, or more hp hiding? if it were reeds totally unable to keep up you'd hear them & the power curve doesn't flatline like fluttering reeds, infact it pulls nicely to 13 & the curve has the same shape & humps as the previous engine at the same revs, which is hardly surprising. Rules out the slipping clutch too.

I'm thinking internal friction on the crank.

Bugger; maybe there is something in the fact you had to press the main bearings in???

[F5 Dave]

or the crank is slightly wider when set up loose & we took a touch skim from the faces. Thought that would have been accounted for with my thicker centre gasket. Might need to remachine bearing deeper or a thicker gasket still. Where's that cork sheet?:confused:

[husaberg]

so what did the crankcase reed MK2 end up looking like Dave.
Did you end up deleting the balance shaft.

Like these.

<img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=248224&d=1318129304" width="373px"/><img src="http://i.ebayimg.com/t/Honda-RS125-crank-case-set-98-07-HRC-RS125-/00/s/NDgwWDY0MA==/$T2eC16d,!yME9s5qIFncBQOYp)zDKQ~~60_12.JPG" width="340px"/>

Its amazing how much these Swedish MB50 ones end up looking like the Honda RS ones:cold:

[F5 Dave]

Yep & yep pretty much. 100 crank is bigger so the biggest compromise of the deal is the inlet does neck down a little more thank I'd like, but it does mean it fits into an RS chassis.

Well after striping the engine I find a litany of problems. Bore looks horrible & so does piston, can't see a good ring seal going on there. Hmm big end has been grazing the reedstop plate just as it comes up there is enough angle to touch it. There's only a 1mm of material chamfered off but I think its been enough to do the damage to the bore finish & rark the piston, ring, little end & pin.

Crank is still giving more resistance than expected. Back off the case bolts a turn & give a tap with the mallet to open them. Spins freely & hey! the gearbox is freer too.

So yesterday took the day off & had a great day at the zoo with the kids. In the arvo went to see the local kart guy & on the spot he honed the cylinder & had another ring & pin in stock (I had a spare brg & piston). I'd also pulled the left bearing off the crank & taped up the rod & spun the crank in the lathe with some sandpaper strips for 20 min until the bearing just about slide on.

I was worried about the crank after all this & Stu checked it & it was like spot on. Schweet!

The bearing shop had a bearing & all I needed was some thicker gasket paper. last was .75 so I really needed 1.2mm. Figured I'd get some 0.5 & have to sandwich them. Walked in & on the carpet in the corner was a big roll of 1.2mm.

After dinner I cut a couple of gaskets (1st one always has mistakes) & fitted it all up & with some heat slid all the bits together & pushed the cases together by hand the last few mm of the dowels. Crank is free as but gave it a tap each was to ensure as free as can be.

Finally a stretch of luck. My mood was hiccuped as tightening the last reed bolt it sheared. Took block off again. In a really inaccessible point but there was 5mm showing. Pliers started it turning easily & it just wound out!! Whoohoo.

All back together now on the bench. A quick leaktest this morning showed promise, but the inlet manifold is leaking again. I must make it a gasket, clearly the original isn't cutting it with some goop. But overall I should be able to dyno it in the weekend.

I'm glad I did get to the track as there were a few things I just don't think I would have found without a shake-down test of the new engine. But having the time to re-go through things was well useful. Mike was totally right, the crank I wasn't happy with, it needed a re examine. The cases were licked & obviously more than a tickle came off so along with slightly wider (looser built crank) the cases were just too close together & needed a thicker gasket.

[husaberg]

The bearing shop had a bearing & all I needed was some thicker gasket paper. last was .75 so I really needed 1.2mm. Figured I'd get some 0.5 & have to sandwich them. Walked in & on the carpet in the corner was a big roll of 1.2mm.

After dinner I cut a couple of gaskets (1st one always has mistakes) & fitted it all up & with some heat slid all the bits together & pushed the cases together by hand the last few mm of the dowels. Crank is free as but gave it a tap each was to ensure as free as can be.




I am sure Dave is well versed in Gasket making but if anyone else isn't but i use a combo of Grease to stain the gasket paper i apply a little pressure to ensure a accurate outline with a rounded piece of wood and a ring spanner to mark the holes by turning the ring end inside the holes in the crankcase timing cover otr whatever.
I always punch the holes with a bit of sharpened Ariel as it makes nice holes and is available various sizes and normally lying around.

All this was shown to me by an old school mechanic.

[F5 Dave]

I try use darkened sump oil. Last night's was too fresh. Gasket paper in this case too thick to impression. Isn't an Ariel an old english nail? I meant the bike not the tack. I just use hole punches, tap & turn. Only about $20 a set.

[husaberg]

I try use darkened sump oil. Last night's was too fresh. Gasket paper in this case too thick to impression. Isn't an Ariel an old english nail? I meant the bike not the tack. I just use hole punches, tap & turn. Only about $20 a set.

Brocket Telescopic Aerial free and about 10 different sizes in each (Available most car parks)
as i'm to tight for punches and for new oil also too.

So you did end up ditching the balance shaft tunnel on MK2?

[F5 Dave]

Ahh Koatanga! Had no idea what you were on about. Car Aerial.

Never run a balancer in any of them, even my H '(cause when I got it it was disabled).

[husaberg]

Ahh Koatanga! Had no idea what you were on about. Car Aerial.

Never run a balancer in any of them, even my H '(cause when I got it it was disabled).

old Radio ones work well too
But wasn't the tunnel left in place for the balance shaft on the original (modded case induction) crankcases?
I was just wondering if you used the counter-balancer area on this version as it would make for a straighter inlet track as above on the Swedish MB/Derbi?

http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=248221&stc=1&thumb=1&d=1318126518

[F5 Dave]

Mk1 I could have run the balancer if I needed to, but tract was horrible, mk 2 looks like pics pretty much which was the obvious progression. But mine doesn't look like it was done with a chisel. Theory is all very well, but I'm nowhere close to the power I was getting with Mk1 so we'll see if that changes.

[husaberg]

Mk1 I could have run the balancer if I needed to, but tract was horrible, mk 2 looks like pics pretty much which was the obvious progression. But mine doesn't look like it was done with a chisel. Theory is all very well, but I'm nowhere close to the power I was getting with Mk1 so we'll see if that changes.

Ah... the inlet track airflow etc (or any other part assuming it's not a stress raiser) doesn't give a damn what it looks like.
i think that's Cameron isn't it? (Paraphrased a bit.)
the Swedish inlet is shaped a little better than mere chiseled (i am assuming you meant the swede)
As you know smooth may look cool but the reed valve covers most of it anyway.

I suspect there a re some minor details holding your new one back, rather than anything major.
I tried to find the close up of the crank-reed (in hindsight i think it was another swede that done it rather than Roffe) (Found later attached below)

If Vanessa is ever finished. The next one will be a Disk valved Mb100 or NSR125/100.

<img src="http://hem.bredband.net/henrik_john/block14.JPG" width="565px"/><img src="http://hem.bredband.net/henrik_john/insug1.JPG" width="565px"/>
<img src="http://hem.bredband.net/henrik_john/block18.JPG" width="565px"/><img src="http://hem.bredband.net/henrik_john/reed11.JPG" width="565px"/>
<img src="http://hem.bredband.net/henrik_john/block16.JPG" width="565px"/><img src="http://hem.bredband.net/henrik_john/block13.JPG" width="565px"/>
<img src="http://hem.bredband.net/henrik_john/block12.JPG" width="565px"/><img src="http://hem.bredband.net/henrik_john/DSC00289_resize.jpg"width="565px"/>
<img src="http://hem.bredband.net/henrik_john/block15.JPG" width="565px"/><img src="http://hem.bredband.net/henrik_john/block18.JPG" width="565px"/>

[F5 Dave]

that thing is a piece of shit, it has far too much weld & will be porous as all fuck. RS125 cases often turn to junk after a few years & can't make the same power as they used to, but that has no chance of not breathing through the welds. The pretty black paint won't help it.

Maybe it will produce good power despite the issue.

[husaberg]

that thing is a piece of shit, it has far too much weld & will be porous as all fuck. RS125 cases often turn to junk after a few years & can't make the same power as they used to, but that has no chance of not breathing through the welds. The pretty black paint won't help it.

Maybe it will produce good power despite the issue.

Meowll bad night Dave:gob:

Welding cases is, as you say not ideal but there is products made esp to seal casting's.
For instance all the Aprilia cylinders were "Hippled" (whatever that process is) Me i would just use a proprietary sealer myself.
With sand casting or welding up old cases rather than pressure di casting issues can occur,
but a piece of shit, i'm sorry no, i disagree with you there Dave, even if it wasn't a Honda :shifty:

[F5 Dave]

Alcohol, what can I say?

Either way what do you care?, its not like you made them.


Back to my thread rather than some random bike on the other side of the ocean. Bike runs much freer & sounds quite different, rattly even. That clean up has made it a tickle looser, but not as noisy as it was with the YZ piston. First up just about 22hp. Tickle back & forward & not much better, just break.

Well at least its better & will do for the BOB. Next I must try the un-flowed reedblock & some other reeds. The ring I have had a bit of clearance so I'd like to test for seal. The other issue that I haven't had time to fix is the transfers are a bit proud of the piston at TDC & the ex timing is a bit down on before, but I really was expecting the other 'improvements' to compensate. The end result cares not for what 'must' be better, which is why you have to test.

[Fooman]

all the Aprilia cylinders were "Hippled" (whatever that process is)

Hipped = HIP = Hot isostatic press(ing).

The casting (and it is generally only used for castings) is heated to sort of near the melting point (or a temperature at which the alloy can creep - time dependant non-elastic deformation) inside a pressure chamber. High pressure is applied (e.g. 100 MPa, depending on the tempature/alloy/component), and the resultant pressure acting equally on the casting (the "isostatic" bit) closes all the non-surface breaking porosity/voids in the casting, via a creep deformation and solid-state diffusion "welding" mechanism, but without gross deformation of the casting.

Is commonly used on cast turbine blades, where the porosity can act as crack initiating defects. Also done as part of powder metallurgy production processes, very much like sintering.

I'm not sure how it would work on closing a through leak however - there has to be a pressure seal for the HIPing to work, and if there is a surface breaking crack, it won't seal - the HIPing gas (Argon) will just get in. There may also be a diffusion brazing process involved if that is the case, or it could just be used to prevent the formation of a crack in service (initiating at a casting void).

Cheers,
FM

[F5 Dave]

Well its been an eventful last 2 meetings, the BOB in Chch & Kaitoke Enduro. Both had engine failures so I'm not covering myself in glory.

I did note that my boostport is restricted by my repair so that has been ripped off & done again. New piston & rings to follow (after I strip the bottom end to get out the remainder of the piston) & maybe a tickle-up with my new RA grinder if that works (experimental system). Piston goes lower than transfers now destroked, so want to correct that.

[F5 Dave]

To add to the drama a piece of piston got caught between the BE & the cases & broke the cases & bent the crank or twisted it out of alignment.

Hope to have it back together for next meeting, but it is delaying the other projects like fitting up the Ignitech which requires a new backplate, but who's got time when I'm having these issues?

[crazy man]

good luck thanks for answering the carb qestion. how much power have you got out of your 50?

[speedpro]

An FXR is looking better and better :dodge:

[husaberg]

To add to the drama a piece of piston got caught between the BE & the cases & broke the cases & bent the crank or twisted it out of alignment.

Hope to have it back together for next meeting, but it is delaying the other projects like fitting up the Ignitech which requires a new backplate, but who's got time when I'm having these issues?

Shit you are having a rotten run of luck Dave.
You did change the cases from the originals, as well too didn't you.
I guess the longer mine don't go the less it will blow.....

[F5 Dave]

I was a bit lucky with the cases as they are a heap of work & non std mounts. It just ripped the ally so I taped it back into alignment & dremeled a groove to fill with devcon as non load bearing area at bottom of crank.

[F5 Dave]

Getting bored with this. Done a heap of work to correct the transfer floors & a few other things. Ran piston in today at a secret testing track. Seized lightly again. I'd noticed it felt a little flat so in spite of it always showing best on the 290 jet on the dyno in many incarnations with these mods maybe it needed a bigger jet, so I changed from the 300 I was running to the 310. better. then to the 320 that it wouldn't pull before. better still. Then it nipped slightly. bizarre. Only slight mark so should clear up.

[crazy man]

Getting bored with this. Done a heap of work to correct the transfer floors & a few other things. Ran piston in today at a secret testing track. Seized lightly again. I'd noticed it felt a little flat so in spite of it always showing best on the 290 jet on the dyno in many incarnations with these mods maybe it needed a bigger jet, so I changed from the 300 I was running to the 310. better. then to the 320 that it wouldn't pull before. better still. Then it nipped slightly. bizarre. Only slight mark so should clear up.bet your sick of it Seizeing . have the cases had some heavy welding done to them? maybe the top of the cases need re maching square to the crank.. l guess you have new seals in the motor.

[F5 Dave]

Only real light welding as I've learnt that lesson, rest is devcon. new seals, new everything, wanted to make a good start rather than the crap I'd been working with. But it hasn't panned out. I've never seized so much is a gross understatement. The last bike was my MB50. Hmm.

Had leak tested it, very small leak so I devconed it.

Felt it get a little draggy & then it just rattled so I pulled the clutch. Popped the head & couldn't see anything obvious until I got to the other side & after a min decided it was ally. I'll pull it down tonight.

[crazy man]

l have never liked devon ..alway welded everything but had to be bolted to a ground plate and job had to be refaced afterwards

[F5 Dave]

Porosity of the cases is a real concern particularly with 70s Honda casting metal. I believe the terminology of the time described it as "Rice burner Shit metal", but I'm sure Honda had another name for it.


Both cases were bolted together either side to a sturdy custom drilled plate of steel before welding. Makes getting the custom mounting holes in the same place on the next set easier as a by-product.

[crazy man]

its not as silly as a blocked brether in the tank? and then running lean? nice to see it running good.. must have to have a closer look at what you have done

[F5 Dave]

you know the tank 1 way valve did fall off when I dropped the cap, I could have put it around the wrong way, don't think so, but I'll look, but it didn't ever feel like running out of gas.

[richban]

Might be time to invest in some gauges. I am looking at running an EGT CHT gauge to tune the new engine. Especially since I will be messing with ignition soon. Got to be a good option.

[F5 Dave]

I've got a knock gauge but it wasn't powered up / hasn't been calibrated, must do that.

[crazy man]

just run the det counter on my bike.only 1 det after 10mins of running so looking good

[F5 Dave]

Well the fuel cap was on the 50 not the 100.

Another depressing session on the dyno. I've made a number of 'improvements' which 'just have to be better'. Lowering the floors of the transfers so they were flush with the piston crown at bdc, I made a good job of it blended in nicely without trumpet shaping it & also rounding off the bottom of the transfers that I'd never bothered doing on this interim barrel. I'd found the boost port repair I'd done had necked it down so redid it to return close to stock. The head now seals properly.

What I hadn't done positively was seize it, but it cleaned up ok & the ring looks ok, but is it sealing as well? - wish I had a ring seal tester (I'm almost about to make one). Also with the head step gone the compression ratio & squish are a bit low & high respectively. I'd got the barrel skimed but it wasn't enough somehow & squish is 1.2mm & that .4mm extra has lowered the comm over 2 points + I'd reshaped the head a bit as it was a triangular shape.

The upshot of which is on the dyno it was pretty poor but after feeding it some more jets (320MJ up from usual 290) & advancing the ign to max available it almost got back to where it had been, but not as much as on the old f'kd cases.

Another difference from the old cases is the reedblock & reeds. New is a much straighter shot, less obstructed & less necked with a flowed reedblock. Time next to try raise the compression, but also try some new reeds & maybe a dirty unflowed reedblock.

Got home at 10 & decided to make a captive spacer for the front wheel & then another for the spoked hub for the wet wheel. All went well so as therapy I laced the rim & got it to within 5mm of straight & tried it in the forks to see how much it has to come over. 12:30 by then so to bed to be finished later.

[F5 Dave]

Well what I had found was the bore/ring seal was poor. like 36% leakage on a ring seal tester. that isn't good when an aircooled KT100 is ~8-10% for example.

So I'm honed & re-ringed & going to run in on Castor oil.

Engine back together & just needs to get slid into frame for next weekend.

I've redone the head in a closer to toroidal shape & 15:1 comp which is pushing it for an air cooled but should be good for now.

Hopefully this will capture a bit more charge in the head & produce a better power spread.


But will it be ready for Taupo, erm Tokoroa?

[F5 Dave]

Well I can't catch a break it seems.

Over last few meets I've had the RS ign, the RM80 & borrowed RM125 ign all fail. I now have a repaired RM80 one back.

So can I get this to ring seal? I've run a few meetings with castor. ign issues aside I should have a good seal now but my leak tester wasn't playing ball. But I could hear the wind rushing by. It must be leaking still. Last race meet it kind of went ok, but not fantastic. Compared to the 50 its grunty, but not really.

As I lay in bed I remembered how it used to be harder to push start with 14:1 ratio & the YZ piston. Its 15:1 & easy as the 50 & doesn't lock the rear ever if you don't pressure the seat enough like it used to. Waddle forward & dump the clutch. Brrum.

So I lay awake one night thinking about the engine placement & the rubber bushes I borrowed from the RG50 engine to help isolate it. They are pretty sloppy in application, the issue is unlike the RG50 there is no decent front mount. But the whole plot is held in line by the head stay. When you change gear I'm sure you can feel the engine moving a bit as the next gear goes home.

So the headstay is solid (the RG engine has one rear solid & one rear & one front rubber).

Maybe this is twisting the bore enough to cause issues & why I am getting polishing & not enough seal.

So I've made some acetal inserts & the whole plot is much more sturdy, + I'll rubber the head stay so it is never a full issue.

Last race it felt like it was overheating a little & just didn't have enough puff. Ordered a piston at the track for next over time to retry again.

To find when I pulled it down; the ring tips had broken off:eek5:. Seen this plenty on my old MB50 with 1.5mm rings, but I'm doing pedestrian revs compared to a KT100. Ring ends in open boostport, but plenty of engines like this.


As I said I'm finding it hard to catch a break. By now I'd hoped to have the ignitech & watercooling sorted & be onto the proper barrel & pipe, but I can't get past teething problems. Even so I should be at a decent power level, but its merely ok.

Will it be ready for Tokaroa? Well going I suspect, but I can't see me setting fastest 1st qual this year.

[speedpro]

My ring ends run over the boost port and the motor revs over 14,000. I haven't lost a ring tip. Genuine Yam KT100 parts. Losing the tips will cause big problems. We used to lose a tip now and then on the MB100 sidecar. You knew instantly when it happened.

[husaberg]

Are you using Mb100 cases i guess you are.
<img src="http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=268216&d=1344979459" width="340px"/>


Most if not all the H100 have the Front mount, but no doubt you already know this. and are unwilling to give up on your modded cases
I guess Mikes motor is mounted similar using the same bore material and rings, so assuming everything is square and true to the cases some weird stuff is happening for sure.

[speedpro]

Using the front mount is risky. Dipy went through a few cases when they broke. I only use the rear two mounts and have an alloy plate under the head bolts which connects to the chassis rails using little brackets. That alloy plate also provides a convenient mounting place for the radiator and ignition.

[koba]

Most if not all the H100 have the Front mount, but no doubt you already know this.

Ever seen the front 'mount' used to mount the engine?

I believe it's designed for leg shields ad not up to the task, so I've been told.

[husaberg]

I just read Mikes post i wasn't suggest to ditch the top but if Dave is right with his theory and he uses the other three mounts as well.
I guess Mr Dipose might have not used all the other three and- or deleted the balance shaft.


Ever seen the front 'mount' used to mount the engine?

I believe it's designed for leg shields ad not up to the task, so I've been told.
like the CR80;)

http://www.cyclechaos.com/images/thumb/1/1b/1980-Honda-CR80-Red-8411-3.jpg/640px-1980-Honda-CR80-Red-8411-3.jpg
If you don't believe me have a look at the crankcase of a 80-83 model and see the unused half machined balance shaft housing.

The cylinder spacing of the 100's the stroke of 50 but with a bigger pin. The air cooled CR80 is a mix and match of the H100 and MB100 and MB50.
<img src="http://www.mb5.co.uk/resources/engine+12.JPG" width="340px"/><img src="http://img.inkfrog.com/pix/independentcycle/NZT49RQMMXNJ.JPG" width="340px"/><img src="http://thumbs2.ebaystatic.com/d/l225/m/mKdXeHKZm6xUml3yUR7sJqg.jpg" width="340px"/
H100 Cr80
But yes some of the last H100 had a fo-full cradle but it was a bolt up section. doubt it did much other than making it look more acceptable.
http://www.whitedogbikes.com/images/Breaking_Bikes/honda-h100s-main.jpg
The later MBX and so forth had conventional frame and very similar crankcases as well.
Later the mounts although very similar are actually different position to the Cr80?mmmmmmmm not so sure now..........

[F5 Dave]

My first iteration used the front mount, this was 15 years ago & shortly after when others were starting to mount MBs into different frames they were breaking cases. Those front mounts are on a really thin part of the cases. Dave was by far not the only person to find this, I've replaced cases for John's bike & there was another set in his collection (bought from someone else) thus afflicted. H100s are the same, well almost the same, but for point of this conversation the same.

CR80 has much more webbing.

So next iteration was not to have that mount used.


I had to cut the std top mount away as the big carb would have hit it. That sounds silly but case reed is very different from Mike's picture, although there is Frits's idea of shortening the inlet that could sidestep that but create other case problems.

Either way if I had a custom set of mounts for the top I might as well for the bottom as they stick a mile away from anywhere useful on an RS chassis. Besides the cases were custom to make them case reed. I have a plate for making new cases in the same place.

[jasonu]

Why you guys waste your time with the MB stuff is way beyond me. If it was any good don't you think more people would be using it?

[kel]

Why you guys waste your time with the MB stuff is way beyond me.

You know you want one! Might as well have Chris off load that pointless hoard of old KE motors.

[F5 Dave]

My H was stoneax reliable. People don't build 2 strokes, they buy FXRs. Don't want to follow the crowd.

Anyhoo I have the new piston, just getting it honed. Kart guy reckons the Kart tech rings are less supported at the tips & the Yam ones never break tips ever, the tech ones occasionally on real high rev'rs. Looked like a bit of chamfering at the boostport which I'd assumed happened after the tips came off, but he pointed out that there was no 'gap' where the tips were gone so it happened when the ring was new. We'd gaped a size up ring so it might have been too tight. Yam rings have heaps of ring gap so that won't be an issue this time.

[jasonu]

You know you want one! Might as well have Chris off load that pointless hoard of old KE motors.

any suggestions as to what to do with that worthless stuff...

[F5 Dave]

Don't sell it, keep it for when that coal burner turns out to be rubbish & sound dreadful.

[Grumph]

My H was stoneax reliable. People don't build 2 strokes, they buy FXRs. Don't want to follow the crowd.

Anyhoo I have the new piston, just getting it honed. Kart guy reckons the Kart tech rings are less supported at the tips & the Yam ones never break tips ever, the tech ones occasionally on real high rev'rs. Looked like a bit of chamfering at the boostport which I'd assumed happened after the tips came off, but he pointed out that there was no 'gap' where the tips were gone so it happened when the ring was new. We'd gaped a size up ring so it might have been too tight. Yam rings have heaps of ring gap so that won't be an issue this time.

From memory there isn't a lot of the original reed housing left on your barrel...I'd reckon that box lends quite a bit of stiffness to the std casting.
Cromwell said to the house of commons "I beseech you in your bowels to consider you may be wrong"....There are people on here who are getting good HP without case reed mods.
And no - i didn't know Cromwell....old but not that old.

[speedpro]

With the KT piston and rings don't forget that you buy a piston and size the bore to fit, then fit the correct size ring for the bore, typically one size up from that marked on the piston. It isn't like the jap pistons and oversizes where the numbers match. I check the end gap and if it's big go up one size ring and check the ring gap again.

[speedpro]

We use MB engines because they are small and light and the sweet MB50 6-speed gearboxes go straight in. Nowadays in the light of recent tuning knowledge the cylinders limit things a bit with limited port T/A and achievable blowdown with the single exhaust port. I have a twin port motor running, not your standard bridged port setup, at the moment which is running reliably but only making lowish power. Plenty to try on the dyno yet. Plus I have a triple port cylinder which is a long way off running but should be interesting with knowledgeable input.

[husaberg]

They were the best of what was available. esp back in the 100cc days
the major limit i see now days is the cylinder stud placement and as mike said the exhaust and Cylinder reed i have a RSV copy set up in front of me with triple exhaust beautiful transfers but if one was to be attempt to be fit one to a MB there would be very little Honda left in the crankcases.
Its going to be a struggle to fit one to the much larger NSR.

The MB/H100 is a Robust little engine and Mikes make 300HP/liter Which is impressive by any standards.

[F5 Dave]

With the KT piston and rings don't forget that you buy a piston and size the bore to fit, then fit the correct size ring for the bore, typically one size up from that marked on the piston. It isn't like the jap pistons and oversizes where the numbers match. I check the end gap and if it's big go up one size ring and check the ring gap again.

yes & yes that's what we did with the next 0.1 size up ring, but it appears the ring gap may have been insufficent even when gapped to typical KT clearance. I'll check whatever Yamaha gave me this time & not run it any tighter & see if we can get this working ok.

Heck I was pulling 24hp with the YZ piston, leaking cases & a reedblock that was a dirty big hole & pointed into the crank webs with little area above the webs to flow & the side 1cm edges of the reed bigger than the crank so hitting metal. With a shorter tract & flowed reedblock the correct size, aimed below the barrel in sound cases with a much better shaped head, a piston with thinner ring & transfer bottoms rounded off this time (gave my old H 1hp when Sketchy did it) I had been expecting to get some 1/2 way decent power.

My original wc'd MB barrel I did 16 yrs ago had a triple ex, just it leaked like a sieve with a hole in it.

I'm up at 4 in the morning planning restarting a WC head (well its a std one cut down but needs finishing), but its all just a bit pointless if I can't keep the basic plot together.

Another GP a year older & a bike that isn't going to be up there in the pwr stakes. (not that I've finished the GP on this bike yet).

[koba]

From memory there isn't a lot of the original reed housing left on your barrel...I'd reckon that box lends quite a bit of stiffness to the std casting.
Cromwell said to the house of commons "I beseech you in your bowels to consider you may be wrong"....There are people on here who are getting good HP without case reed mods.
And no - i didn't know Cromwell....old but not that old.

Valid thoughts.

My next step had been rattling around in my head lately.

To use the RS frame I have I need to change engines or make the MB100 fit.
Making it fit is major work, it may be possible without going to a case reed but will certainly be damn difficult.

I imagine Dave's case reed builds will have started motivated by power but in light of Mike and others being pushed by big ponies (while using the standard position) I guess it's more about packaging (in an RS frame) than power now.


EDIT: Thankfully we are likely have better treatments for beseeching stubborn bowels than whatever was used in Cromwell's time!

[TZ350]

To use the RS frame I have I need to change engines or make the MB100 fit.Making it fit is major work, it may be possible without going to a case reed but will certainly be damn difficult.

If its the carb thats getting in the way, you could try one of these 24mm Tillitson HL360A's, they are very compact and easy to tune.

[F5 Dave]

Actually that may not be a bad sort of idea. the carb is considerably in the way. I've seen Diesel's shock & wasn't prepared to go that way & I'd considered knocking a frame rail out but it is major work to both frame & SW. I've also considered linkage in conventional manor, but the SW is too narrow.

[Grumph]

Valid thoughts.

My next step had been rattling around in my head lately.

To use the RS frame I have I need to change engines or make the MB100 fit.
Making it fit is major work, it may be possible without going to a case reed but will certainly be damn difficult.

I imagine Dave's case reed builds will have started motivated by power but in light of Mike and others being pushed by big ponies (while using the standard position) I guess it's more about packaging (in an RS frame) than power now

Invert the bastard - and reverse the barrel.

[TZ350]

Team ESE RS/GP125's use the original rear Honda engine mounting position (un modified) and hang brackets from it that pick up the rear top and bottom mounts on the engine case. The front uses an original piece of the Suzuki frame and the Honda RS frame gets a rubber vibration bush and is heavily re inforced where the front engine stay stay plate bolts onto the frame.

I will see if I can take some better pictures of how Av's and NedKellys engines are mounted in their frames when I get back to work Wednesday.

[F5 Dave]

Yeah the GP engine looks far easier, I've had a look around Katie's project, simples by comparison.

[speedpro]

I've severely chopped and welded a set of MB cases with a view to fitting them to an RS chassis. The problem remains that the carb mounting rubber perfectly lines up with the shock mount crossmember and is only about 5mm away. The only answer I see is to cut away the cross member and mount the shock somewhere else. A newer model RS chassis would help but the budget says no, sort of like Cyprus. I asked the Germans but they are, well, Germans and not leaping at the opportunity to invest. I even offered to join the EU.

[koba]

I've severely chopped and welded a set of MB cases with a view to fitting them to an RS chassis. The problem remains that the carb mounting rubber perfectly lines up with the shock mount crossmember and is only about 5mm away. The only answer I see is to cut away the cross member and mount the shock somewhere else. A newer model RS chassis would help but the budget says no, sort of like Cyprus. I asked the Germans but they are, well, Germans and not leaping at the opportunity to invest. I even offered to join the EU.

This photo of yours really shows it quite graphically:

http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=150299&d=1257661670

[koba]

Invert the bastard - and reverse the barrel.

More smarts, but more hurdles; un-even stud spacing!
Again, possibly do-able but not if adhering to KISS.




I really do like the idea of a reverse cylinder.

[husaberg]

This photo of yours really shows it quite graphically:

http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=150299&d=1257661670

Whats does the Mutt fit like?
Can't recall seeing a pic?
I have my own suspicions my engine while potentially being a better fit (assuming they ever meet)won't allow a decent intake as a mount is very close Maybe to close. The nsr125 and 150 have a Uber long kinked intake standard.

[koba]

Whats does the Mutt fit like?
Can't recall seeing a pic?
I have my own suspicions my engine while potentially being a better fit (assuming they ever meet)won't allow a decent intake as a mount is very close Maybe to close. The nsr125 and 150 have a Uber long kinked intake standard.

Great, except the frame is too long and weight ends up too far back.
If the frame rails were cut and shut with shorter forks it would work really well.

There is enough Room to fit a wanked CBR150 engine in there very well...

[cotswold]

There is enough Room to fit a wanked CBR150 engine in there very well...[/QUOTE]

I think Rick tried that and it didn't fit, he may have an older chassis?

[koba]

There is enough Room to fit a wanked CBR150 engine in there very well...

I think Rick tried that and it didn't fit, he may have an older chassis?[/QUOTE]

Sorry, talking about my 250 in that one.

[F5 Dave]

Well its been a few late nights but the 100 is back together with the engine mounts changed somewhat & hopefully giving the barrel some relief from the potential twisting it may have been getting before.

Now to run it in on the dyno & get some decent base settings that's all there really is time for.

So it will be ready for Taupo. Again. Even if it isn't Taupo this time. Gearing is a bit of a worry, I've run out of time to make up some more sprockets for the rear so will have to suffice with front changes. oh yeah the chain is a bit naff, might have to spring for a new one if the budget allows.

So its been the 50 that has needed some attn.

I usually give it a new ring before the GP each year. But I haven't gone near the bottom end since 2004. Try that on your FXR & spin it to 14.

Clutch gave some grief meeting before last & there wasn't that much oil in there. Hmm. sure it'll be fine with some more oil & new clutch inner. Next race, gee its smoking a bit Dave. Hmm, ok gear box crank seal. Ordered seals ($11) & haven't had the time to pull it down. ok so check & evidence of blow by on seal (& wear on seal, prob due to oil oil level).

Some brass in the bottom. 1st gear bush shagged. Buy some beer, swap for gearbox.

While I'm here I might as well polish the crank so the bearing is a slide fit on both sides. Bearings were a bit of an issue but I've got some C4s plastic cage ones for both sides, but have to machine the groove for the snap ring so its with a toolmaker this morning.

Ported this engine back in the dark ages, maybe I'll give it a look over. Hmm, bottom of transfer to bore pretty sharp, give that a tickle. Piston could have a tickle in same area.


Hmm reedblock on back of barrel could be a bit obstructed by back of barrel, I'll just grind that a bit. Wonder why I never did this before? Hmm piston skirt obstructs this at BDC esp now I've tickled the bore spigot. I'll just shorten the piston skirt a bit, probably about 4mm, there's heaps of skirt for support. Gee I wonder why I never did that before?

Just as finishing grinding. . . . Wirrrr- CLICK. Oh yeah, that's right, its not full reed, there's the piston port inlet to consider:rolleyes:. Opps. So either I've made the bike more peaky, or it will suit the rev range its in & be just fine.

Found the new spare piston, so I will run the numbers & fit that if its looking a bit rad on inlet, or just try it on the dyno.

Hope to catch up on sleep thurs night.

[speedpro]

I reckon you will get away with 202-205 degrees duration on the inlet on your 50. Any more could be asking a bit much of the clutch.

[F5 Dave]

Well I measured it & maybe it will be fine.

Remember this is the suzuki RM(RG) like setup 1/2 reed, 1/2 piston port.

The 4mm off has taken it from a rather conservative 162* to a whapping 182.5*. According to the old Bell book for 12,000 195-200* is the go for piston port & minus 15* for an RM reed, which takes it to 180-185*, so smack in the middle of the recommendation & a little to spare as the 50 peaks at 13 not 12.

I think I'll give it a try & see how it goes, may even be better peak, but as we know spread is always better (just not always that possible on a 50).

engine complete & on the bench. Might slide off early & throw it in the frame & take both to the dyno.

[F5 Dave]

Well that was depressing. The 50, well it goes pretty much the same as before but now can fall into the Blarrhs & get loaded up pretty easy. If on song it won't be an issue. So I don't know whether to change the piston back or not. Sounds like a bit of bother, but if it did load up it would be a drag. Before going I found the muffler perf tube was broken so tried to weld it but made a sleeve & reriveted it as it was just blowing apart.

So a bunch of work done & no benefit, although I have the variable of the piston skirt & the fact I could see a bit of light around the new ring when held to the light so perhaps the bore is just a bit oval.

The 100 was worse. Think I got somewhere between 18 & 20hp, but the graph stopped showing after about 9000 & reappears after 12-13000 for a few mm. Clutch obviously slipping. Didn't seem to get any better.

Get home, drain oil. All sorts of questions running through my brain, but its well past 11pm.
Why is it slipping despite an extra plate clutch & MB100 springs with a few mm extra preload so they almost coil-bind?
How much power could it be capable of producing if that was fixed?
Is the tuning about right now for best power, 'cause I just can't tell when you can blatantly control the slip with the throttle.
And where is all that Ally dust in the oil coming from?

Got cover off & it appears the clutch cush drive rivets have come off. Haven't seen that before on a std basket. Rubbing on case. flush ally dust.

Replace basket & scuff up modified steels & find some more plates that are ea 0.06 thicker & std springs that are almost a mm longer.

Have to decide whether to dyno again or just assume 32hp & aim for a good sleep.

[speedpro]

2 things to look at in the clutch.

1 is the washer between the inner and outer hub and basket? Is it the correct washer? If it isn't there every time you pull the clutch in the back plate will rub.
2 This is a possible problem with my modified clutches. Have I machined the bottom of the inner hub enough? I think there is a slight possibility that if I haven't cut it back enough that the first fiber plate you put in can bind up on step on the inner spline. This could be where alloy is getting in the oil. If it's slipping make sure the whole clutch pack is being clamped including the first clutch plate you put on when installing it.

I can throw a some spare bits in the car when I come down.

[richban]

2 things to look at in the clutch.

1 is the washer between the inner and outer hub and basket? Is it the correct washer? If it isn't there every time you pull the clutch in the back plate will rub.
2 This is a possible problem with my modified clutches. Have I machined the bottom of the inner hub enough? I think there is a slight possibility that if I haven't cut it back enough that the first fiber plate you put in can bind up on step on the inner spline. This could be where alloy is getting in the oil. If it's slipping make sure the whole clutch pack is being clamped including the first clutch plate you put on when installing it.

I can throw a some spare bits in the car when I come down.

Also look at the oil you are using. I ran my bike in at manfield once. Motul semi synth in for a while, clutch slipping like crazy. Changed oil to the expensive double ester and it never slipped again.

[F5 Dave]

2 things to look at in the clutch.

1 is the washer between the inner and outer hub and basket? Is it the correct washer? If it isn't there every time you pull the clutch in the back plate will rub.
2 This is a possible problem with my modified clutches. Have I machined the bottom of the inner hub enough? I think there is a slight possibility that if I haven't cut it back enough that the first fiber plate you put in can bind up on step on the inner spline. This could be where alloy is getting in the oil. If it's slipping make sure the whole clutch pack is being clamped including the first clutch plate you put on when installing it.

I can throw a some spare bits in the car when I come down.
1. yes that is std castelled washer
2. Hmm, trouble picturing what you are saying but I think I checked & the steels had clearance. When putting together I pull the inner basket & then put on the springs, but it is fiddly.

The clutch had been un touched for 3 meetings & hadn't seen a problem, well, maybe it ran out of gearing up the hill in 6th that could have actually been clutch slip when I thought about it as most load in tallest gear.

The ally came mostly (all?) from the case by the primary gear where the backing plate of the cush drive had come away when the rivets broke & was turning some grooves. Didn't look particularly safe thing to do at 12,000rpm.

Those clutches wobble quite a bit so I put a precautionary thin shim behind the whole plot so that middle washer hasn't got 3mm of movement, only 1mm slop now.


But yes I could be desperate for a fix if this doesn't work so all spares gladly begged for if you have something that could help Mike.

I grabbed a bottle of Elf gear oil & I think that went in the 100 when I put it together, never used it before. Back to my std Motul transoil for the newer plates.

[F5 Dave]

Well after my GP debacle where the clutch stopped disengaging, the basket is back together with some peened bolts & the btm end spilt to replace the bearing behind the clutch that got mullered by the precautionary washer mentioned above + the gear shaft polished to remove said washer debris. Bottom end back together.

Thoughts turned to the ignitech that I've had for ~10 months. I'd made a spacer for centralising the stator & just getting some material set up for the outer spacer. A mate showed up sat night & over a bottle of wine or so I've run most of the wires required to get it to run. When I fit the stator I'll test it for sparks & then wrap the loom. I've branched off the wires near the back of the bike (I mounted ign under the seat after some debate but best waterproofing for non faired bike) that will eventually be for power jet, TPS, shifter & so on if I get around to those things.

I've left the other wires in the loom & they can be unwrapped & provide output to tacho, shift light, input for knock sensor, power for EGT or whatever else, heck I may need to get an upgraded output regulator if I fit all this stuff.

But the main impetus is to get power so I can run the water pump & that will be next, however the ign should net some power by itself as the RM one wasn't as good as the RS, & the RS could be adjusted for best midrange or best top, but not both. Some extra over rev would be very appreciated.

[crazy man]

maybe time to see the light like bert (-:..:laugh:

[richban]

maybe time to see the light like bert (-:..:laugh:

He he he. Coz Bert has a 4 stroke that will go all the time. he he he.

[F5 Dave]

So,like how often has Berts bike stopped lately?:rolleyes:

[Bert]

maybe time to see the light like bert (-:..:laugh:

Shit stirrer


He he he. Coz Bert has a 4 stroke that will go all the time. he he he.

Yet another one.


So,like how often has Berts bike stopped lately?:rolleyes:

:baby: lots; could make a list but no one would bother reading it anyway. Found a couple of major issues that need to be redone from scratch (mainly the sleeve that didn't have a top step in it, thus when she got hot in welly earlier in the year the sleeve dropped)... :(

So long winter of building again for the next north island series and GP (lucky I'm so busy that I've not got time to race anyway). :niceone:

[F5 Dave]

oh, I thought it had gone pretty steadily since the bearing debacle. Actually Dave did mention something about the sleeve.

[crazy man]

Maybe that's a coincidence that it’s written next to RS125 then isn’t it?


Bullshit dispensing time:

Depending on the dyno (so lets talk std dynojet) the average RS will put out late 30s. A pretty damn good one about 45. Overseas big $ trick one about 50.

There is probably only one bucket touching 20 hp in Wellington & it belongs to Speedpro. My old H100 did 17 & kicked the butt of most (dunno about now with the pipe change & airbox/jetting).

With another barrel/pipe (when I almost won the Chch Battle of the Buckets 4 yrs back, before the bottom end died a few laps before end) it measured 24hp on a pretty optimistic lower hutt bike shop dyno. I suspect this would read 20hp on a dynojet. Made it too hard to ride on kart tracks.

Anyone claiming 22 hp in wgtn is deluded or measuring on a dyno that reads high.

[crazy man]

l like old posts

[F5 Dave]

Why? At the time it was totally true

[crazy man]

Why? At the time it was totally truel know but fun looking at them. funny how things change. never thought 30hp at rear was possable

[crazy man]

24mm carb is pathetic even for a bucket!
So whaddayareckon? The F4 125 aircooled 2-stroke rule to limit carb size to 24mm is quite a limitation. Probably why there aren’t any fast aircooled 125s.

I mean compared with a water cooled hot 100 that may be running a 34 (RS 125s run 39 & bigger) the 24 has an area of 452mmsq compared to a 34 of 907mmsq. That’s half the size for a piddly extra 25cc & aircooled to boot!!

So who wants to front up to the next MNZ doodacky & give those poor 125 guys a boost, say 28mm might be better? (615mm).

Actually there are some guys I believe who are running 28s & none of them seem to be cleaning up.

[crazy man]

ha ha eat your words:sick:

[speedpro]

I've been yakking to the Wobbly one and he's confidant of getting at least a few more than 30hp nowadays. If only I had nothing else to do.

[F5 Dave]

Ok have to take the heat on that one

[jasonu]

24mm carb is pathetic even for a bucket!
So whaddayareckon? The F4 125 aircooled 2-stroke rule to limit carb size to 24mm is quite a limitation. Probably why there aren’t any fast aircooled 125s.

I mean compared with a water cooled hot 100 that may be running a 34 (RS 125s run 39 & bigger) the 24 has an area of 452mmsq compared to a 34 of 907mmsq. That’s half the size for a piddly extra 25cc & aircooled to boot!!

So who wants to front up to the next MNZ doodacky & give those poor 125 guys a boost, say 28mm might be better? (615mm).

Actually there are some guys I believe who are running 28s & none of them seem to be cleaning up.

Um fuck that. ESE and Green get 30hp from their 125 aircooled 2 strokes. They don't need any help in that department.

[husaberg]

Um fuck that. ESE and Green get 30hp from their 125 aircooled 2 strokes. They don't need any help in that department.

Specially Green he is getting 30 hp with only 100cc already;):p:nya::whistle:

[F5 Dave]

Well a little more progress, I've half made the WC head from a cut down MB aircooled one, getting a threaded extender welded on so can take long reach plugs. Will make covers & devcon it together.

Have made some rad hose adaptors & glued to the pump so its ready to go. Oh hey? Where's the pump power on my loom schematic? Hmm, better fix that, think I was pontificating where to mount the pump, but it will be down low near rad exit so no drama.

Loom has progressed a bit further & should create sparks. Engine back together & in frame, just short of some C/S screws to hold ign plate on but I'll mickey up some to do some tests.

Then I can add bits to the loom as required as the spare wires are all at the front. I've split off, connector'd & taped over the TPS, PJ & quick shifter branches for later date. Might get around to fitting the shift light for giggles.

[kel]

Might get around to fitting the shift light for giggles.

Go all the way and install a rev counter. The ignitech can drive pretty much any 3 wire tacho, my one's off an RGV250.

[F5 Dave]

yeah I've got the RS125 taco (opps sorry thinking about Mexi food tonight) but it stopped working, so I need to try fix it. Later.

I'm re cutting the dash foam out of thicker foam & will mount an array of dash items to dazzle the rider with information.

I have a heads up crash detector which simulates (rather too realistically) the image of tarmac sliding past the visor when a crash situation has occurred:eek5:.

[ac3_snow]

I have a heads up crash detector which simulates (rather too realistically) the image of tarmac sliding past the visor when a crash situation has occurred:eek5:.

sweet! I have been tempted to instal some lunch control on my bike, just got other issues to work through first.

[F5 Dave]

Good idea, one doesn't always need a slice and fizzy as well.

[Henk]

sweet! I have been tempted to instal some lunch control on my bike, just got other issues to work through first.

I'd quite like lunch control as well. I seem to ride better in the afternoons when I don't forget to eat.

[Yow Ling]

I thought lunch control was those special lower fairings MNZ are bringing in to catch all the oil when diesels lunch themselves

[Henk]

I thought lunch control was those special lower fairings MNZ are bringing in to catch all the oil when diesels lunch themselves

Never seen a diesel go out to lunch.

[F5 Dave]

Well a productive but not so productive few days.

Few pics first, first up is the RS muffler that has had a birthday as I want to knock the sound back a touch as the RS muffler is a bit short these days. Gave it to Damon to fix as easiest option & it has a reversal in the end section, all of which is larger di than the stinger so should prove no restriction. reused the old RS interface at the front.

Next is the start of the watercooled head. I turned up a spacer & got it threaded & welded to the top so I can run long reach plugs (have to weld or it just creates a hotter plug + could potentially leak a little).

I had to retain the headstay so this was easiest, not much stress on it. The cardboard will be replaced by ally & devconed in place. Outlet pipe once cut down welded to plate before putting it together. Inlet bolted to plate at front. I'll run just the head first & then externally loop to the barrel.

The pump is mounted at the front old RS engine mount & can rotate to suit either scenario & should be crashproof.

The last pic is the combustion chamber of skimmed head & just matched to piston angle. I need to shape the chamber & have taken a Kneedit mould of the Aircooled one for reference. That said as it is now at about 25:1 size it should suit the pure Methenol I plan to run, should be allright eh Kel?:innocent:
My son insisted that 'Jack' pose with the picture.

[F5 Dave]

So the saga of the Ignitech & the Evil of the Honda Motor Corporation;

The stator is on nicely once I sourced some long cs screws & I've pinned the base to stay in one location as its all SW positioned from now.

The loom I'd got pretty much there, but it was time to try it out.

No spark, mess around, mess around. Try with & without battery. Find an issue with the connectors I'm using. No spark still.

Hmm, that battery lead is warm. Ekk.

So try just the output from the regulator spinning the engine with rear wheel. (-)12.5 V. - MINUS?!?!!

I hadn't had a schematic of a CR, but the input was pretty easy & there was a black wire & a browny/red. Those two clearly are the rectified regulated output. Just Honda chose to use the Black wire for Positive. When I turn it over I see a thin thin stripe of red on that wire.

You Pricks, that's just Evil. Red & black wire was too difficult?

Anyway now that's fixed. With a battery to the system the igni box buzzes slightly, but draws no current & I can't get a spark. Hope I haven't goosed it. Didn't have the sw loaded on my laptop, so I'll try communicate with it later, I didn't have the right cable either but last night whilst lying awake worked out I could plug it in using the 3" of cable fitted.

[kel]

Dont use Methanol, it will send you blind then kill you!

The ignitech will make an audible buzz/hum/electrical noisy sound, when power is on.

My bike is flying now that we have the timing sorted, wheel spinning and wheel standing around Mt Wellington! Damn thing threw me off twice. I guess dirty old Avgas will have to do :cry:.

[F5 Dave]

Wondered why you weren't in the results Dave sent through.

Well it makes the noise so that's a start. I've got a cable & the SW so I'll plug it in tonight & see if it will talk. There's also the test fire if it does.

[kel]

Could you try the ignitech test output for the tacho (once working), mine will only read 5k rpm no matter what value I set in the software. Would be good to know if others have this problem or not.

[F5 Dave]

Heck I don't know if I've bricked it or not yet. + my RS tacho is goosed & needs some love.

[husaberg]

So the saga of the Ignitech & the Evil of the Honda Motor Corporation;

The stator is on nicely once I sourced some long cs screws & I've pinned the base to stay in one location as its all SW positioned from now.

The loom I'd got pretty much there, but it was time to try it out.

No spark, mess around, mess around. Try with & without battery. Find an issue with the connectors I'm using. No spark still.

Hmm, that battery lead is warm. Ekk.

So try just the output from the regulator spinning the engine with rear wheel. (-)12.5 V. - MINUS?!?!!

I hadn't had a schematic of a CR, but the input was pretty easy & there was a black wire & a browny/red. Those two clearly are the rectified regulated output. Just Honda chose to use the Black wire for Positive. When I turn it over I see a thin thin stripe of red on that wire.

You Pricks, that's just Evil. Red & black wire was too difficult?

Anyway now that's fixed. With a battery to the system the igni box buzzes slightly, but draws no current & I can't get a spark. Hope I haven't goosed it. Didn't have the sw loaded on my laptop, so I'll try communicate with it later, I didn't have the right cable either but last night whilst lying awake worked out I could plug it in using the 3" of cable fitted.


I have a wiring diagram for the Cr's here

Honda even evilly transposed the CR500 and the CR250 in the Hayes manual.
Only thing i remember and take for granted with the ondas was blue is right (for the indicators)
I was going to try and find a GSXR 6 or similar tacho....
I guess it would read half but got confused weather i would or not?

[F5 Dave]

yeah I have one too & it sez red & green, must be different year.

[husaberg]

yeah I have one too & it sez red & green, must be different year.

I just noticed it also says 97-98 new models similar (Using the wrong, but obviously right, CR250 97-98 "cause it has a PJ solenoid diagram" as i said)

[F5 Dave]

Well I haven't bricked the igni which is encouraging to say the least. I can get it to talk to the Lapps and spark using the test fire function but can't get it to fire otherwise.
Says wrong polarity no signal but changes its mind every so often. Odd but no sparks. Not helping tuning process for this weekend.

oh yeah could adjust tachometer output in test mode but didn't have one to plug in

[speedpro]

Rob helped me get mine going. There were odd fault indicators initially with the trigger signals. Rob probably still has my configuration on the ESE laptop. You can have it to get going if it helps.

[F5 Dave]

Thanks was thinking that might help. Also considering if your set up is limited by key position to a max advance? Still uncertain how they calculate it if different to zeal I've used on the 500.

[speedpro]

In the Ignitech software in the "bike" tab there is a checkbox for "no lobe length check". That could be something worth testing. I have a problem with the laptop and can't check if I saved my configuration on it.

[F5 Dave]

Thanks i'll give it a look

[F5 Dave]

Well my first big issue was just that I didn't tick the 'program on change' box so changes I made didn't occur, sparks followed pretty quickly thereafter once I'd figured that.

Next was I had to start the bike to get the timing sorted.

A short foray to the dyno got me one step forward & 2 back. Got best power level so far but worse every change thereafter. Plugs I were using were left overs & fouled up with lots of dicking around changing curves on the lappy by myself while bike was running down on dyno (no starter on dyno so have to keep bike running but not over heat so only do a change or two). Need more hands next time.

Either way I have to try find a suitable short reach resistor plug for the weekend. After that I'll finish the new WC head which will take longer plugs.

Sure is pretty peaky currently with a big hole before power, but trying to tune it out was pointless with crappy plugs. Hadn't bought any more as expected to be on long reach plugs by now.

Hard to get used to switching the bike on & off on the dash rather than the kill switch I've had on every race and dirt bike for the past 25 years.


Shift light is pretty. Not sure if it will be sunlight readable yet.

Kaitoke this weekend. unless it is filthy wet.

[speedpro]

Give it heaps of advance in the mid range, that'll get rid of that hole, in the power curve. You may find another hole though, about 1/2 way round on the third lap.

I ended up with a flat timing curve on my MB. We took a few degrees out right at the top but it would have been fine without doing that.

It is pretty cool being able to dick with the timing. Dyno tests years ago pointed to huge gains in the mid-range on my TS100 if I could advance the timing in the mid range. We're talking from 9hp to 15hp. Advancing the timing with the fixed curve killed the top end though.

[F5 Dave]

Well it was a bit soggy to 5000 & giving it conservative 20deg dropping off cleaned things up quite nicely. My big drop is at 11,000 which is not a pretty place to have it, that said the plugs were old & crap & non resistor, but I've found Supercheap sell resistor short reach BR9HS for $6 on special so I've bought a couple for the weekend & will then move over to Long reach fine wire plug on WC head.

Mike I've considered running the water pump with a relay & using the output 1 that I can't think of a good use as it turns on after 4 seconds. Currently I just have it attached to rail. That said even with battery disconnected it seems to start right up.

Maybe its just safer, if the relay fails wp turns off = bad.

[speedpro]

My pump is hardwired to the generator reg/rec output. The engine starts in a few steps even after 3-4 weeks without use.

[F5 Dave]

well it was hosing on Sunday, nearly left to go play on the dyno but was talked into racing.

Had some teething issues due to slap dash preparation (like the battery wasn't fitted, but I'd pulled the lead cover insulator back to run the timing light & that was grounding stopping sparks.

At the end of the day it was going quite well. Certainly fast when up on the plane, but needs more work below.

What I can't seem to fix is launch from starts. I suspect it is the RGV carb just doesn't like high revs low- mid throttle position. Splutters like a bitch & just falls over & takes a while to clear. Then front wheel claws the sky as you chop it into 2nd.

Maybe its the needle, maybe I need to go up on the pilot or something, but it works well enough in the dry while riding it, but has always been hit/miss on starts.



Another option is I just try fit the mondo carb & be done with it, see if I can get that to work any better.

My shift light is pretty & actually is helpful in absence of a tacho (must try fix that RS one some day).

Anyways the next step is finish the WC head & back to the dyno.

[F5 Dave]

Well the LC head is pretty close to done. Got some outlets welded on & was convinced to weld the front section to the top section for strength as the pipe will be pulling on it. Sounded reasonable. Had to warm up the Devcon as it was a bit old, but got soft enough. I also glued in a splitter so if at a later date the water is piped in at a bit of an angle it shouldn't favour one side.

Well it definitely looks 'Bucket'. . or Russian. if I get carried away I'll knock the sharp edges off & give it a shot of etch.

The more observant of you might notice that there are no holes to bolt this to the engine, but I will continue the existing holes from underneath. No point giving myself the pressure of lining everything up before it was glued. I will however have to line up where I have the dowels on the other head, maybe with some form of stencil, engineering blue & clear plastic sheet.

Pump is hard wired on. Temp gauge fitted & Det gauge as well, though I have to loom fiddly coax loom & connector. M8 hole on side of head is for sensor.

[jasonu]

Well the LC head is pretty close to done. Got some outlets welded on & was convinced to weld the front section to the top section for strength as the pipe will be pulling on it. Sounded reasonable. Had to warm up the Devcon as it was a bit old, but got soft enough. I also glued in a splitter so if at a later date the water is piped in at a bit of an angle it shouldn't favour one side.

Well it definitely looks 'Bucket'. . or Russian. if I get carried away I'll knock the sharp edges off & give it a shot of etch.

The more observant of you might notice that there are no holes to bolt this to the engine, but I will continue the existing holes from underneath. No point giving myself the pressure of lining everything up before it was glued. I will however have to line up where I have the dowels on the other head, maybe with some form of stencil, engineering blue & clear plastic sheet.

Pump is hard wired on. Temp gauge fitted & Det gauge as well, though I have to loom fiddly coax loom & connector. M8 hole on side of head is for sensor.

Fuck mate that looks 'factory'!

[F5 Dave]

The factory being Jawa Motokov perhaps:mellow:

[RMS eng]

The factory being Jawa Motokov perhaps:mellow:

maybe the sponge Bob factory, Nice

[F5 Dave]

Well I've knocked some holes in it, next to enlarge 2 for the dowels. Then check the chamber volume as it was made slightly smaller than a template to be sure.


Then I'd better hit the corners with a file

[jasonu]

maybe the sponge Bob factory, Nice

I was thinking more like the Affro Engineering Company...

[F5 Dave]

Well I machined the holes & Mill cut some dowel holes that hopefully line up with the barrel. I'll compare head volumes on the bench one head to the other & adjust from there & it should be plug & play.

My proximity switches for the quickshifter showed up today, I've already loomed it to the main loom so its another connector & a bracket & that will be fitted if I can find a nice posi that it won't get clouted. Then I can turn it off & on in SW if it works.

[F5 Dave]

ok happy? I even filed the sharp edges. If I was really keen I'd have devconed the shape uniform & engraved HRCCGGF on the side (HRC can go get F'd).

Actually in my haste I have forgotten to test for seal, but that will just be 2 blanked off bits of hose, one with a schrader valve to pump it up & dump in some water, I have those bits from testing my 500.

Also the head bolt nuts that were shortened for the skimmed head are now too short so I'll run std ones, but I might have to ruin my paint job by recessing the holes a couple of mm to be sure they have heaps of thread. The head is covered in like 7mm plate ally. I could have gone skinny ally but having some thermal mass is a good idea for a head as I have found in previous efforts on my old MB50 when I got too greedy on weight savings.

[RMS eng]

[QUOTE=F5 Dave;1130573440]ok happy? I even filed the sharp edges. If I was really keen I'd have devconed the shape uniform & engraved HRCCGGF on the side (HRC can go get F'd).

Actually in my haste I have forgotten to test for seal, but that will just be 2 blanked off bits of hose, one with a schrader valve to pump it up & dump in some water, I have those bits from testing my 500.

Also the head bolt nuts that were shortened for the skimmed head are now too short so I'll run std ones, but I might have to ruin my paint job by recessing the holes a couple of mm to be sure they have heaps of thread. The head is covered in like 7mm plate ally. I could have gone skinny ally but having some thermal mass is a good idea for a head as I have found in previous efforts on my old MB50 when I got too greedy on weight savings.[/QUOT
thats a works bike trick to paint things black so they look like a stock part?.suzuki in the 70s painted the alloy swingarms on their mx works bikes to look like a stock steel arm.Dave i will put up a photo of my RG80 motor that i want to sell and you can go to town on it.

[F5 Dave]

Well won't crow too loud, it leaks like a sieve. Devcon I used was quite old so maybe too old. Might have to try get it apart & start again Que some localised heat. Sod.

[F5 Dave]

Well I knocked it apart after some strategic propane torch application on the joints. Course it may have been helped by the fact I cured the paint off at 50* in the oven. But forgot to remove it. Then the wiff turned the oven on to warm it for dinner. Maybe the Devcon didn't like 200odd degrees. Sure stunk out the kitchen:innocent:

But it was pretty old stuff that I had to soften in front of the fan heater.

I've started the gluing process again in stages using JB Weld that is a whole lot newer.

[jasonu]

[QUOTE=F5 Dave;1130576098]Well I knocked it apart after some strategic propane torch application on the joints. Course it may have been helped by the fact I cured the paint off at 50* in the oven. But forgot to remove it. Then the wiff turned the oven on to warm it for dinner. Maybe the Devcon didn't like 200odd degrees. Sure stunk out the kitchen:innocent:

QUOTE]

Now THAT is some funny shit!!!

[Moooools]

Well I knocked it apart after some strategic propane torch application on the joints. Course it may have been helped by the fact I cured the paint off at 50* in the oven. But forgot to remove it. Then the wiff turned the oven on to warm it for dinner. Maybe the Devcon didn't like 200odd degrees. Sure stunk out the kitchen:innocent:

But it was pretty old stuff that I had to soften in front of the fan heater.

I've started the gluing process again in stages using JB Weld that is a whole lot newer.

Reminds me of some guys who had a very leaky custom engine so the night before the race they painted the whole lot in high temp epoxy and stuck it in the oven to cure (at the motel they were staying at in aus). But someone forgot about it and ended up burning all of the resin and stinking out the motel with the smell of burnt plastic. They still let us stay there, although thankfully no more custom engine.

[F5 Dave]

Well its back together & gave me time to have a 2nd look at how to do it. I spread goop around the mounting hole bosses (with spacers) as leaks there can't be fixed & then in the next stage of epoxying, turned the head upside down so goop would flow down hopefully sealing those unions. I roughed up some of the ally as the clear chromate doesn't stick too well it seems.

I also put it in a box in the bedroom in front of the heater to cure. Warned the wife about it & again in the morning but she still tripped over it.

[mr bucketracer]

maybe buy your old engine back and use it as a hunderd instead of a fifty this time
http://www.trademe.co.nz/motors/motorbikes/parts-for-sale/complete-engines/auction-612308138.htm

[F5 Dave]

Nothing to do with me, Chris made that many moons ago, he'd shown me it in his garage a ways back when. To be honest, at the time set up right it would have been a pretty sensible bike, forerunner of Diprose Derbis. Giving away 20cc it won't be easy to be a front runner now, but keep a mild FXR honest, for sure.

[F5 Dave]

Well I've run some chemweld through it & it seems water tight now. Measure the com & it was as I'd planned; a bit high, so another tickle to correct squish & take some more out of the bowl & its where it should be. Pretty high, but I'm losing a bit in the rings so might as well squash what I have left a fair deal. I'll trial less comm later with another head.

Started up & I found some leaks, this time seemingly the hoses, but also the water pump. The adaptors I'd turned up to go from std rad hose size to the pump, which is a teeny 10mm, well I'd chosen Acetal as it was to hand & easy machine. Of course its pretty slippery stuff & didn't want to glue that well it seems. I went & bought some Plastic toy glue which states it covers nearly all plastics & also metal. Couldn't find any other plastic tube scraps so I might just make some ally ones & glue that.

Det sensor needs to be bolted on head & the loom for it (re) made. Quick shifter needs a bracket. Whether I get around to either of these I'm uncertain, have to concentrate on what I need to race on sunday.

[F5 Dave]

So I made some ally adaptors & glued them to the pump last night, will attach it tonight hopefully.

Hmm glue drying. water out might as well fit the det sensor to the head with some loctite in the threads so it hopefully seals. I'll rig some temp wires to power it, but I need to do job properly later so it is removable when taking the head or the instruments off, - just its shielded wire.

I could see if I could whip up a bracket for the quick shifter sensor. . . with a few tweaks it is hopefully in the right position. An LED lights up when it is activating as the linkage comes forward & there is a good 5mm side clearance so it shouldn't get clouted.

Along with the shift light there will be enough on board entertainment on the dash, - why worry what is going on on the track? :blink:

Talk about techno bucket.

[F5 Dave]

Ok Chris &Jase, laugh yah bar studs. Head held for a few runs &then started to drip from the front. Still it showed some promise of a healthy gain, but I might need to get it welded and hope it doesn't go too soft. Deciding whether to try patch it for Sunday or just run water and top it up. Lost 50cc over many runs testing which was about 1cm down the rad.


Quick shifter works but needs some time on triggering so will have to wait for setup.

[F5 Dave]

Well quick look and test. No leaks. WTF? Ahh seems the chemweld clogged my pump hose. Blew that out and leaks aplenty. Ground some trenches and re glued. Hope holds for Sunday

[husaberg]

Don't know what product you are using, but many moons ago we used to use a Chesterton product (not sure which it was) but it was used for Dicast chainsaw poo metal. That was unweldable
http://www.matweb.com/search/datasheettext.aspx?matguid=88cb0b17f8494ddba9c6c8e 7797a1c91

[F5 Dave]

JB Weld this time, people use it for 4stroke inlet ports so should easily cope with temps

[mr bucketracer]

pays not to make a head out of devon:killingme

[koba]

pays not to make a head out of devon:killingme

Yes, otherwise one would have a mighty large head:
http://en.wikipedia.org/wiki/Devon

But it would be quite 'Torquay'.

[jasonu]

Ok Chris &Jase, laugh yah bar studs. Head held for a few runs &then started to drip from the front. Still it showed some promise of a healthy gain, but I might need to get it welded and hope it doesn't go too soft. Deciding whether to try patch it for Sunday or just run water and top it up. Lost 50cc over many runs testing which was about 1cm down the rad.


Quick shifter works but needs some time on triggering so will have to wait for setup.

But will it last a race meeting???

[mr bucketracer]

just cast a new head , 3 hours to make some paterns

[Drew]

just cast a new head , 3 hours to make some paternsI might be falling victim to bucket racers sarcasm here, but is that realistic?

I expect a lot of chopping up of a head that almost works now, to fuck it and maybe end up with bung moulds and no head at all.

Dave, did Sketchy go about water cooling his MB in the same fashion you are?

[F5 Dave]

But will it last a race meeting???

Don't know. I've trenched & glued & retested this morning. Leaks are 10% of what they were. Will redo one bit tonight & should be sound enough.

Will it deteriorate during the day? I'll keep a check & its only a fun day so a good day to test. Have the 50 there so can ride that if I'm losing water. there is heaps in the system & the pump is near the bottom & has a good head so it won't burn out the head.

[F5 Dave]

pays not to make a head out of devon:killingme
thanks, remind me to laugh at your misfortune.

[F5 Dave]

I might be falling victim to bucket racers sarcasm here, but is that realistic?

I expect a lot of chopping up of a head that almost works now, to fuck it and maybe end up with bung moulds and no head at all.

Dave, did Sketchy go about water cooling his MB in the same fashion you are?

I think he turned it & o-ringed, he had offered me it to use, but I wanted to press on with my own shape chamber + mine is doweled. I'd been avoiding doing the full weld as you can make the ally so soft it just warps & leaks pressure & warps again. Can heat treat them but done properly that costs quite a sum of money.

I have a nice billet Sketchy gave me a while back that I could have used but this looked easier.

[mr bucketracer]

thanks, remind me to laugh at your misfortune.you will have you chance if you alread have not. do you think the head casting of ziffles bike would work ?

[F5 Dave]

One of the other reasons for keeping MB part was the headstay is still used, but thanks anyway, I did make up a bolt on one, but I'm back to the MB through head nut-bolts as long studs (from case to top of head) were a pain on last engine.

[speedpro]

My method with a head plate with under the studs and then small brackets to connect it to the chassis works well. I transferred my engine to Dave's RS50 and just made another plate and little brackets to connect to his chassis. The plate is at right angles to the bore so the worst vibration is fed solidly to the chassis which has worked well for me. Plus it provides a handy place to mount ignition coils and stuff.

[F5 Dave]

OK so epic fail. Did practice, few drips. Topped it up. Race one it started off ok but was making a funny noise, few laps in I was spending more time looking down so decided to pull in. Was in comfortable lead but something wasn't right. Didn't get to go head to head with Rich to see if fast or not.


had a quick look. . .

Side of jacket was missing. Oops. Couldn't swap to ac head as forgot shorter head sleeve bolts.

ok weld it time. 50 did the biz for rest of day.

[kel]

I transferred my engine to Dave's RS50
About that, isn't it time the motor was returned to the FZR chassis? Those boys can't be trusted don't you know.

[mr bucketracer]

Yeah I haven't ridden the F4 many times, but one of the more memorable races was Taupo that year it rained cats & dogfish. I crashed the H on the old turn 1 flat out & had to kick the bike away 3 times before I was free of it & hit the dirt still sliding fast. I got to it pulled the clutch & jumped back on & tried to take off in 6th Bwooah, change change Bwoahhh, change change & was off again, left side of bar twisted in 30degrees.

I was running old Yoko 110s, but the front was virtually bereft of tread so I figured I'd just go for it. There was quite an attrition rate but I also found a groove & was hauling in people, not that it mattered I figured. But I saw Dave ahead in the distance & the red mist came down so I passed him & gapped a little. No doubt this caused Dave to figure there was some more traction & he started hauling me back bit by bit & I was getting the feeling my luck was running fine every time the front tucked on T1.

I got taken a bit off the track by a madman Grifith on the hubcentre 100 when he passed me & promptly crashed & I think that's when Dave got close enough to pass. We only had a couple of laps to go but I figured there was no point battling for a nowhere position. Little did I know I'd been in 2nd place for a good deal of the race.

But the funny part of the story is when I came back to the pits someone said Gee Dave, - your bleeding! Eh? Sure enough dripping out of my leathers. Sheet!, didn't even know I was hurt! Took the leathers off which now weighed about 40kg, remember it had been raining heavily & I'd done the F5 & F4 GP. My leathers were leaking a heap of red dye. Phew!
....( the bad griffiths got the best crash of the day award to ) what a slide!! ) sorry old post

[F5 Dave]

I can still remember it pretty clearly , brave,but you were never going to stay on long on slicks at that speed in that deluge of rain. Or if you did what would I have done for an excuse?

[mr bucketracer]

I can still remember it pretty clearly , brave,but you were never going to stay on long on slick at that speed in that deluge of rain. Or if you did what would I have done for an excuse?as i remember it went for alot of laps , i was thinking where is the limit on this bike so pushed it harder and harder . coming off had to happen some time . just peed off the ziffle bike broke a wire . i was leading it up to then . then thought dam it i will ride the centre humb for the rest ever though 2 laps down. l know dennis that won it was not pulling away from us . coilen never told me it empteyed the float boil all the time to.

[F5 Dave]

ok well here is Mk2 version. Same same but different.

Bottom where it attaches to the casting has gone a little porous, but is to be expected with crap 70s Honda castings. 2 stroke gets impregnated in holes, could be smelt when welding apparently.

Either way I'll chemweld treat it & hopefully it will do the biz. Shouldn't fall apart this time! Hope it hasn't gotten too soft.

[F5 Dave]

Well a bit of luck, as I pansied out of riding in the wet I figured I'd take a quick trip to the dyno instead. Ran the bike up. Temp was slowly increasing (sensor in top of Rad not head as it gets interference from plug + its std RS position). But put hand on head. Hmm, that's hot! much hotter than before when it was realll cool. Then it got really quite hot. Carefully took the cap off & localised boiling.

Put a battery on & turned it on. No noise from the pump. Tried the spare pump I just bought (isn't fitted to swap over yet). It worked.

Got it home & found a wire broken. Pump juts against engine, so vibation at the interface could have broken it. Rewired it & made a pad + shortened a hose to reduce the issue.

Glad I didn't race it, I wouldn't have noticed.


Which made me wonder. Obviously this had happened in the last race meet. A contributing factor in my Devcon'd head falling apart?

[Drew]

Which made me wonder. Obviously this had happened in the last race meet. A contributing factor in my Devcon'd head falling apart?The rattle from the devcon'd head was there on lap one. Got worse on lap two. Next time or time after that you came round, and the bit bounced out and accorss the track. After one lap, I wouldn't haved thought it would be over heating...other than not having any water in it.

[F5 Dave]

Could have stopped working in practise session before. Warm up laps would have easily overheated a non circulating system. It was quick to get real hot.

[Drew]

Could have stopped working in practise session before. Warm up laps would have easily overheated a non circulating system. It was quick to get real hot.True. I would have thought that the radiator cap would have vented before the pressure pushed the head apart. But the system is hardly tried and true, so maybe not.

Lets work on the theory that the welded head will stay flat, and never speak of it again aye?

[F5 Dave]

Well here's the next inevitable step. Milling the fins took several hours & although I would have preferred the have a central inlet & outlet I opted for diagonally opposed for packaging reasons, like the outlet at the front has to go through a formed bit of Rad hose to the head & the bend is too tight to do it centrally. Similarly the rear entry (ooerr!) has to miss the head stay to remove barrel in situ.

The front above the ex is narrower but it is deeper so shouldn't be a restriction so hopefully flow around both sides will be equal.

I now have some toque plates so we'll clamp the barrel & jam it in front of a fan heater before we hone it. Hopefully this will reduce the ring seal leakage to, . . .well a lot less than 35% it is now, target 8% like a KT.

Next run Kaitoke 15th, then BOB Ruapuna.


I've also made up an inlet manifold for the 36mm carb so I hope I get the chance to try that out & perhaps gain some enormous advantage.

[jasonu]

Well here's the next inevitable step. Milling the fins took several hours.

Why did you mill the fins off? I used to somewhat carefully bust them off by using a prybar between the fins then finished off the stubborn buts with an angle grinder with a 4.5" hard disk. Never took more than an hour.

[F5 Dave]

The Honda ones are a bit keen. I angle cut off the main work, but I wanted to retain the top & some of the 4th. i wanted to get them a bit flush so the passage could be fairly narrow which is better than a big bucket. Esp as the water pump I'm using isn't particularly high volume.

[F5 Dave]

Well back together & pump seems to circulate water ok, if not super enthusiastically, the rad is large. Anything 70degrees or under is worthwhile doing for 80% of the effect. I'm hoping for 50, but I might need the flash pump & not sure the stator would drive that, the ignitech & the PJ solenoid all at once. + its a bit too spendy at the moment.

jammed the barrel in the heat chamber with the mondo torque plates a mate made up & whisked it up to be honed, but sat it in front of a fan heater. Hone came up best its been, but need to see if this translates to better sealing. 35% leak is miserable.

[Drew]

Well back together & pump seems to circulate water ok, if not super enthusiastically, the rad is large. Anything 70degrees or under is worthwhile doing for 80% of the effect. I'm hoping for 50, but I might need the flash pump & not sure the stator would drive that, the ignitech & the PJ solenoid all at once. + its a bit too spendy at the moment.

jammed the barrel in the heat chamber with the mondo torque plates a mate made up & whisked it up to be honed, but sat it in front of a fan heater. Hone came up best its been, but need to see if this translates to better sealing. 35% leak is miserable.Sorry for my ignorance, you might have already mentioned it, do you want to keep the water temp at 50 degrees or do you mean something else?

How do you measure the loss through ring sealing by the way?

[F5 Dave]

Yeah about 50 seems optimum but anything appreciably cooler than air cooled is worthwhile. Ring seal tester is two gauges and piston locked at top of bore. Feed compressed air in plug and 2nd gauge measures % difference. Should be about 8-10% so 35 is pants.

[Drew]

Yeah about 50 seems optimum but anything appreciably cooler than air cooled is worthwhile. Ring seal tester is two gauges and piston locked at top of bore. Feed compressed air in plug and 2nd gauge measures % difference. Should be about 8-10% so 35 is pants.35% is bad for sure looking at what the aim is. I imagine there is untold fucking around to heat the piston and cylinder before testing, and trying to be consistant with timing of the test.

Think I'll repress the memory of this conversation, so it doesn't cross my mind as the GT gets assembled.

[F5 Dave]

yeah I'm getting desperate so trying all sorts of things. If it seals properly I might get some decent power out of it.

[koba]

Well back together & pump seems to circulate water ok, if not super enthusiastically, the rad is large. Anything 70degrees or under is worthwhile doing for 80% of the effect. I'm hoping for 50, but I might need the flash pump & not sure the stator would drive that, the ignitech & the PJ solenoid all at once. + its a bit too spendy at the moment.

jammed the barrel in the heat chamber with the mondo torque plates a mate made up & whisked it up to be honed, but sat it in front of a fan heater. Hone came up best its been, but need to see if this translates to better sealing. 35% leak is miserable.

Looking Pro!

[kinger]

I know I'm jumping in here, and I haven't read the full thread, but leak downs need to be done on a hot engine, and it's a cylinder seal test, so includes valve seating if it's a four stroke.
Carry on..............

[F5 Dave]

A 4 stroke?! Don't be ridiculous.

And no they don't 'have' to be.

[SS90]

A 4 stroke?! Don't be ridiculous.

And no they don't 'have' to be.

I leak down test every 2 stroke I build (even standard original stuff) and there is always a large difference between cold and hot, and, the smaller the engine, the larger the leak (when cold)

I am unsure of your method, but I assume that you are 100% confident that the leak is from the cylinder sealing rather than anywhere else (exhaust port is very common), and simply spraying soapy water is the method (I am sure you are aware of this)

I have personally never found an engine (yet) that hold the pressure for more than a few minutes (or less) particularly when cold, as it just eventually seeps past the rings, and have only done a few fast 50's myself, but I seem to remember that something like 10% was the norm in all cases (somewhat less than 35)

Have you tried an expander ring behind the piston ring? I use them when I have trouble with ring sealing (Suzuki RG 150's have them on the second ring, and you can cut them to suit for 125's no problem, but 50cc I suspect not..... Maybe some production 50's have them, but I am not sure.

I just had a look in some 50 kits and they all have expander rings, i don't think you woukd have much luck buying just the expander ring, but even a cheap Chinese ring kit (retail something like €5) would have the expander ring.

[F5 Dave]

Your post confuses me. Leak down of cases vs leakdown of ring seem to be interchanged in places. This is ringseal with engine locked and you can hear air leak out the carb and pipe. This is my 100 with a KT piston.


anyway a successful night testing it stayed together. More power so must check seal again to compare. Temp gauge in rad reads way low compared to head temp, I'll have to move it. Thanks to Koba for helping out.

Finally getting somewhere

[SS90]

[QUOTE=F5 Dave;1130611297]Your post confuses me. Leak down of cases vs leakdown of ring seem to be interchanged in places. This is ringseal with engine locked and you can hear air leak out the carb and pipe. This is my 100 with a KT piston.


anyway a successful night testing it stayed together. More power so must check seal again to compare. Temp gauge in rad reads way low compared to head temp, I'll have to move it. Thanks to Koba for helping out.

Finally getting somewhere[/]

Unfortunately I was attempting to write via phone, and I edited it cack handily.

Does the cylinder hold pressure for any time, or leak immediately?

[F5 Dave]

Well straight away, you're feeding pressure constantly from the compressor into the sparkplug hole with piston held at TDC. Ex port is wide open as is carb (apart from having to get past ring & piston).

I must retest it now I've honed it with torque plates, the power has come from somewhere.

[speedpro]

honing it out to 136cc would of helped.

[F5 Dave]

I'm using the piston you suggested & assumed it was legal. but I had to water cool it to build up the material as the bore job went right through and exposed some gaps at the base of the fins:confused:.


Actually when I first fired it up last night the bike sounded notably different. More kind of gruff, & there were some new rattly sounds coming from the clutch area.

It hit me; its because its not ringing the fins - the noise is suppressed, so you can hear other stuff that was drowned out before.

[SS90]

Interesting.... I use a modified blood pressure testing kit (similar to a Kart tilitson pop off tester) to hand pump, rather than a compressor, I have always felt that was too much pressure... How many bar do you run?

[F5 Dave]

http://www.ebay.com/itm/Dual-Gauge-Leakdown-Tester-For-Harley-/140920319644?pt=Motorcycles_Parts_Accessories&hashUm, google ring leak tester. My other crankcase
leakdown tester uses a bicycle pump at 8 psi, but this is a different test altogether.

[Yow Ling]

Are we all on the same page, is this the test we talking about ?
http://en.wikipedia.org/wiki/Leak-down_tester

cant see how you can do this with a blood pressure thing, can see how that would work for testing if an engine is sealed but not leakdown

[Ocean1]

http://www.ebay.com/itm/Dual-Gauge-Leakdown-Tester-For-Harley-/140920319644?pt=Motorcycles_Parts_Accessories&hashUm, google ring leak tester. My other crankcase
leakdown tester uses a bicycle pump at 8 psi, but this is a different test altogether.

Does your rig literature say what orifice size it has Dave?

[bucketracer]

I leak down test every 2 stroke I build ... Have you tried an expander ring behind the piston ring? I use them when I have trouble with ring sealing (Suzuki RG 150's have them on the second ring, and you can cut them to suit.

An expander ring behind the top ring is unnecessary (unless your trying to mask a problem) as the top compression ring does not rely on its static radial pressure for bore to ring sealing. The compression and combustion pressure behind it pushing it outwards does that and no one has mentioned the all important sealing surface formed by the underside of the ring and the lower face of the pistons ring grove.



Interesting.... I use a modified blood pressure testing kit (similar to a Kart tilitson pop off tester) to hand pump, rather than a compressor, I have always felt that was too much pressure...

Are we all on the same page, is this the test we talking about ?

http://en.wikipedia.org/wiki/Leak-down_tester (http://en.wikipedia.org/wiki/Leak-down_tester)

I cant see how you can do this with a blood pressure thing, can see how that would work for testing if an engine is sealed but not leakdown

Looks like, not everyone is on the same page, for a cylinder leak down tester, you need a constant pressure source like a compressor and pressure regulator and a way of forming a pressure differential. A hand pump like a blood pressure thing would not work that well but could work great for a crankcase leak tester.


I assume that you are 100% confident that the leak is from the cylinder sealing rather than anywhere else (exhaust port is very common),

I am not sure why anyone familiar with 2 stroke engines. who pressurizes the crankcase would be surprised that air will leak at the exhaust port or inlet. As the bore is hopefully round and parallel while the piston is neither round or parallel cold and not much better hot, the piston has never been intended to function as a good static seal.

Crankcase leak down is usually done with the inlet, exhaust and spark plug, plugged and looks for bad crank seals, case joints, head gasket etc and for completeness should be followed by a vacuum test.


I have personally never found an engine (yet) that hold the pressure for more than a few minutes (or less) particularly when cold, as it just eventually seeps past the rings, and have only done a few fast 50's myself, but I seem to remember that something like 10% was the norm in all cases (somewhat less than 35).

Anyone who has turned a good engine over by hand will have seen how quickly the compression pressure leaks past the rings, its a matter of a second or two, certainly not minutes and Leakdown % figures have no meaning when compared between different engines unless your using the same leak tester and method on both.

Below was scraped from yhe Wiki link Yow Ling posted.

A leak-down tester is a measuring instrument (http://en.wikipedia.org/wiki/Measuring_instrument) used to determine the condition of internal combustion engines (http://en.wikipedia.org/wiki/Internal_combustion_engine) by introducing compressed air (http://en.wikipedia.org/wiki/Compressed_air) into the cylinder and measuring the rate at which it leaks out.
Compression testing is a crude form of leak-down testing which also includes effects due to compression ratio (http://en.wikipedia.org/wiki/Compression_ratio), starter/battery condition and other factors. Leak-down testing confines the results to cylinder leakage alone.
Testing is done on an engine which is not running, and normally with the tested cylinder at top dead center, although testing can be done at other points in the compression and power stroke. Pressure is fed into a cylinder via the spark plug (http://en.wikipedia.org/wiki/Spark_plug) hole and the flow, which represents any leakage from the cylinder, is measured.
Leakage is given in wholly arbitrary percentages but these “percentages” do not relate to any actual quantity or real dimension. The meaning of the readings is only relative to other tests done with the same design of tester. Leak-down readings of up to 20% are usually acceptable while greater than that requires a repair. Racing engines would be in the 1-10% range for top performance.
In the United States, FAA (http://en.wikipedia.org/wiki/FAA) specifications[1] (http://en.wikipedia.org/wiki/Leak-down_tester#cite_note-1) state that engines up to 1,000 cu in (16 L) engine displacement (http://en.wikipedia.org/wiki/Engine_displacement) require an 0.040 in (1.0 mm) orifice diameter, 0.250 in (6.4 mm) long, 60-degree approach angle. The input pressure is set for 80 psi (550 kPa), and 60 psi (410 kPa) minimum cylinder pressure is the accepted standard.
While the leak-down tester pressurizes the cylinder, the mechanic can listen to various parts to determine where any leak may originate. For example, a leaking exhaust valve (http://en.wikipedia.org/wiki/Exhaust_valve) will make a hissing noise in the exhaust pipe (http://en.wikipedia.org/wiki/Exhaust_pipe) while a head gasket (http://en.wikipedia.org/wiki/Head_gasket) may cause bubbling in the cooling system.

287454


A leak-down tester is essentially a miniature flow meter (http://en.wikipedia.org/wiki/Flow_meter) similar in concept to an air flow bench (http://en.wikipedia.org/wiki/Air_flow_bench). The measuring element is the restriction orifice and the leakage in the engine is compared to the flow of this orifice. There will be a pressure drop across the orifice and another across whatever leaks in the engine. Since the meter and engine are connected in series, the flow is the same across both. (For example: If the meter was unconnected so that all the air escapes then the reading would be 0 or 100% leakage. Conversely, if there is no leakage there will be no pressure drop across either the orifice nor the leak, giving a reading of 100 or 0% leakage).
Gage meter faces can be numbered 0-100 or 100-0, indicating either 0% at full pressure or 100% at full pressure.
There is no standard regarding the size of the restriction orifice for non-aviation use and that is what leads to differences in readings between leak-down testers generally available from different manufacturers. Most often quoted though is a restriction with a .040in. hole drilled in it. Some poorly designed units do not include a restriction orifice at all, relying on the internal restriction of the regulator, and give much less accurate results. In addition, large engines and small engines will be measured in exactly the same way (compared to the same orifice) but a small leak in a large engine would be a large leak in a small engine. A locomotive engine which gives a leak-down of 10% on a leak-down tester is virtually perfectly sealed while the same tester giving a 10% reading on a model airplane engine indicates a catastrophic leak. The non standard size of the restriction orifice determines the reading which therefore differs for each design.
Some manufacturers use only a single gauge. In these instruments maintaining the input pressure is (hopefully) maintained automatically by the pressure regulator alone. Any error in the input pressure will produce a corresponding error in the reading.
In instruments with two gauges the operator manually resets the pressure to 100 after connection to the engine guaranteeing consistent input pressure and greater accuracy.
Most instruments use 100 psi (690 kPa) as the input pressure simply because ordinary 100psi gauges can be used which corresponds to 100% but there is no necessity for that pressure beyond that. Any pressure above 15 psi (100 kPa) will function just as well for measurement purposes although the sound of leaks will not be quite as loud. An engine pressurized to 100psi must be locked at exactly top dead center or it will rotate under the pressure. This presents a serious danger to the operator. Using less pressure is less dangerous and opens the possibility to test at positions other than top dead center.
Due to the simple construction, many mechanics build their own testers and those instruments function perfectly well.

[F5 Dave]

Well I don't think I have much to add after that.

Just waits to see if I destroy everyone tomorrow. 'Course would have helped If I'd stayed sober, but well that's not my style.

[koba]

Just waits to see if I destroy everyone tomorrow. 'Course would have helped If I'd stayed sober, but well that's not my style.

You too eh?

I've got mine ready for an in-frame crankcase leak test tomorrow morning at the track, the devcon will have set by then...


Oh, you said 'everyone' I thought you said 'an engine' as that's what I think may happen to mine...

[Pumba]

.............Oh, you said 'everyone' I thought you said 'an engine' as that's what I think may happen to mine...

Funny, I read his post earlier an that is what I read as well. Wasn't till your post that I picked it up.

[F5 Dave]

Well it all worked pretty well. Comes on pretty sharp. I'm kinda used to that delivery on the 50, just there's considerably more. Made riding in the wet a hazardous proposition & I got totally detuned & while starting out in the lead, the competition destroyed me when I went to pieces.:(

Must buy some wets made in this century. Sorry credit card, you're going to take one for the team.

Fortunately the weather dried up for the 30min enduro so I went out on slicks. There wasn't many of the fast guys there, but no one passed me & after maybe ten min I pulled in. No point wearing the bike or slicks out before the BOB.

Its fairly fast, just need to work on some more spread.

[F5 Dave]

We'll plan for tonight having fitted a new brushless water pump that runs 3x the flow the last one did for almost the same current draw and repositioning the temp sensor in the head and reconnecting the det sensor was to cal the sensor and try a curved ig map instead of the straight 15 deg line I have as a starting point.

but doom, the dyno stops working. Poo. Nothing obvious and no spare time or parts.

did manage at least to give the pump a shakedown and seems ok. Also got det sensor tweaked to at least where I was assuming that was best just off red flashing.

while I was at it I set the quick shifter on the Ignitech up. Seems to work fine but proof will be in the riding.

sadly I have a bored RGV carb complete with homemade solenoid almost ready to test. Might have to stick with what I've got for the BoB.

[richban]

We'll plan for tonight having fitted a new brushless water pump that runs 3x the flow the last one did for almost the same current draw and repositioning the temp sensor in the head and reconnecting the det sensor was to cal the sensor and try a curved ig map instead of the straight 15 deg line I have as a starting point.

but doom, the dyno stops working. Poo. Nothing obvious and no spare time or parts.

did manage at least to give the pump a shakedown and seems ok. Also got det sensor tweaked to at least where I was assuming that was best just off red flashing.

while I was at it I set the quick shifter on the Ignitech up. Seems to work fine but proof will be in the riding.

sadly I have a bored RGV carb complete with homemade solenoid almost ready to test. Might have to stick with what I've got for the BoB.



Quick shifter please. X 3.

[F5 Dave]

So what am I going to do? Maybe I'll have to get obsessed by handling instead:blink:

[Drew]

So what am I going to do? Maybe I'll have to get obsessed by handling instead:blink:
I've always thought this was where all race bikes, should get the builders first attention. Unless they're just throwing a bike together with whatever is lying around, as I do.

[F5 Dave]

Don't be silly. I come from the Wayne Gardner school of thought. Twist it & hold on.


. . .actually I'm not good enough to do that,

[F5 Dave]

Quick shifter please. X 3.
ok I've got some more on the way, I've had one in the van for when I next see you.

[F5 Dave]

Well no dyno time so had to work on the chassis. Mounted the rear Wet to confirm there is clearance (old one rubbed the pre94 sw unless you surgically set it up). Hurrah, the Bridgey wet is narrower so easy as. While wheel was out I took the time to fit the sharkfin. What a windup that was. Trying to drill holes without a RA drill in the middle of a swingarm is a right pain. Course I got it wrong & had to grind the rivets off & redrill the plate so it didn't hit the sprocket bolts.

Gave me time to rearrange the washers so the axle nut bites onto better thread and I can fit an R clip.

Redid the brakes, replaced the catchbottle & hose. Might even pass scrutineering with a smile.

Next need to fit the taller gearing, but a bigger sprocket is off being ground down to 415 & the 15T I used last time is the template for the 16T.


Working on dyno bits now to try fix, wouldn't mind another run or dozen to try a bigger carb etc.

[F5 Dave]

Well it loved the bored out (35mm) carb straight off a decent improvement on top & even upper midrange with 2hp from 9.5-11 so improvements all round.

However as the testing progressed the jet changes stopped making any difference & power was down say a HP. An all gears run confirmed that things were a little worse in the higher gears so I decided to pull the plug and go back to the 32 as its a honey in the tall gears.

I think its something to do with the powerjet & how its flowing. I was driving it wrong at first too, but had it unpowered at the start so its a bit confusing as it wasn't making a difference. I need to do some blow through tests.

However I'd also blown through the PJ at some point, maybe I'd cleared a blockage. You could see the fuel travel int he clear tube so it is working.

So safe is best for the BOB, but more testing required, with a decent promise of things to come.

Time to fit the fairing & front wet onto the wheel & its ready to go. oh yeah & fit my shift light again. Terminal broke. Wires next time.

[richban]

Ok D boy.

Lots of dyno talk but no actual number or graph posted. I think its about time you posted the results of your efforts.

[mr bucketracer]

Ok D boy.

Lots of dyno talk but no actual number or graph posted. I think its about time you posted the results of your efforts.+1 thinking the same

[koba]

Forgive me for leaking it, I can't keep it quiet any more!
288554

[mr bucketracer]

Forgive me for leaking it, I can't keep it quiet any more!
288554i know it was 27.5 the other week so dont beleave that or else dave is a slow rider:msn-wink:

[Bert]

Forgive me for leaking it, I can't keep it quiet any more!
288554

Well done Dr Dave...
Looks like a Honda....

So what that work out at: 1hp per year since the project started (over standard) :niceone:

[F5 Dave]

Forgive me for leaking it, I can't keep it quiet any more!
288554

yeah thanks mate, must be at least double that now I've fitted an expansion chamber.

All will be revealed while you're all sobbing into your beers & I'm drinking (sensibly) from the trophy.

[speedpro]

Dave, looks like he's mixed up your 50's graph with the 100's. Not bad if it's real, not bad at all. Has anyone checked on Rich lately?

[F5 Dave]

I think you'll find its a real graph for an RM125 or something.

[F5 Dave]

Well yesterday pulled apart my shift light for a 2nd time & drilled some holes where the fractured terminals were, soldered on some dangly wire & hot glued it back together. Guess they didn't expect as much vibration in the dash of a Familia compared to pushed against the wobbly number board of a Bucket racer.

Well on the count down with a few tasks left before I drop the bike off to Skunk tomorrow. To come home to a power cut. Smeg. Kids in bed at 7:30, its dark, ahh I'll just put my head down. Wiff comes back from werk at 9 so I get up & don a head torch & LED lantern.

Shift light fitted. Front wet fitted. Carb totally stripped & returned to previous spec in 32mm body.

Also trial fitted the fairing. Needs a little trim with the new pipe from last time I fitted it so that may be tonight's job + pack.

We got power back at 4:30 this morning. Wonderful stuff. Highly recommend those Eveready head torches though. Brilliant if pricey. Never felt compromised.

While I've been thinking I realised that the 35 carb caused peak to be a little higher than the 32 (say 12600 rather than 12200). As my bike heated up the results slumped a little, but what I should have done was adjust the revs on the timing that was now on a sharp curve at that point & more heat put into the pipe as further down the timing curve for new peak power. I've written that badly, but I think it makes sense.

Next I'll do the carb change over compared to other carb with a flat curve then optimise the curve. There had been a few more det flashes with the 35 that I was a bit concerned about. That is energy being lost & backs up the theory.

Either way I'll stick it back to the same spec as tested with the 32 for the BOB. Sorry I didn't take any pics of the curve.

I haven't tried my replaceable stingers since the slipping clutch days. I'm running a 20 straight, but somewhere nearer a 17 or 18 might be more applicable.

And I could shorten the pipe for some more revs.

Then its time to start on a decent barrel & pipe.

[Grumph]

Well yesterday pulled apart my shift light for a 2nd time & drilled some holes where the fractured terminals were, soldered on some dangly wire & hot glued it back together. Guess they didn't expect as much vibration in the dash of a Familia compared to pushed against the wobbly number board of a Bucket racer.

Well on the count down with a few tasks left before I drop the bike off to Skunk tomorrow. To come home to a power cut. Smeg. Kids in bed at 7:30, its dark, ahh I'll just put my head down. Wiff comes back from werk at 9 so I get up & don a head torch & LED lantern.

Shift light fitted. Front wet fitted. Carb totally stripped & returned to previous spec in 32mm body.

Also trial fitted the fairing. Needs a little trim with the new pipe from last time I fitted it so that may be tonight's job + pack.

We got power back at 4:30 this morning. Wonderful stuff. Highly recommend those Eveready head torches though. Brilliant if pricey. Never felt compromised.

While I've been thinking I realised that the 35 carb caused peak to be a little higher than the 32 (say 12600 rather than 12200). As my bike heated up the results slumped a little, but what I should have done was adjust the revs on the timing that was now on a sharp curve at that point & more heat put into the pipe as further down the timing curve for new peak power. I've written that badly, but I think it makes sense.

Next I'll do the carb change over compared to other carb with a flat curve then optimise the curve. There had been a few more det flashes with the 35 that I was a bit concerned about. That is energy being lost & backs up the theory.

Either way I'll stick it back to the same spec as tested with the 32 for the BOB. Sorry I didn't take any pics of the curve.

I haven't tried my replaceable stingers since the slipping clutch days. I'm running a 20 straight, but somewhere nearer a 17 or 18 might be more applicable.

And I could shorten the pipe for some more revs.

Then its time to start on a decent barrel & pipe.

Ah, that's better.....when the dyno chart was posted i thought "he's peaked too early" Now i see it's situation normal....development stops (temporarily) at the dummy grid...

power - try being without for a week as we were recently. Tyre warmer generators are good for keeping fridges going.

[mr bucketracer]

Dave, looks like he's mixed up your 50's graph with the 100's. Not bad if it's real, not bad at all. Has anyone checked on Rich lately?think he of to the dyno after seeing the one on here lol

[F5 Dave]

We lost power for 2.5 days a couple of months back & with two preschoolers in winter it isn't fun, but its only a window of what it must have been like for the hundreds without power in Chch in winter well after the rocks. Makes you waste a bit of heat & hot water immediately after to warm up emotionally. No sir, I don't like it.

[koba]

My wind-up was spotted far too quickly, it was from an RS125 of some description.

[speedpro]

I just noticed the "54mm" bit as well. Rich would be proud.

[F5 Dave]

Well I fitted the fairing last night & with the aid of a bungy which stops the ears drooping I don't have to lower the bars which means it should be comfier than nekid & no more cramped. Needed a little more trimming around the pipe & boots area, but all good.

[mr bucketracer]

My wind-up was spotted far too quickly, it was from an RS125 of some description.think it put rich in hospital

[F5 Dave]

yeah our top 6 finishers side bet is looking a little more shaky.

Get well Rich.

[F5 Dave]

Well the autopsy after the BOB,

slight pick up on ring which was the power loss. New piston & light hone and it back to new. And the rooted main bearing & broken crank/pin. Bugger. So did it muller a main creating the vibration first?

[husaberg]

Well the autopsy after the BOB,

slight pick up on ring which was the power loss. New piston & light hone and it back to new. And the rooted main bearing & broken crank/pin. Bugger. So did it muller a main creating the vibration first?

Mag side Dave?

[F5 Dave]

yup. can't remember what the bearing was but pretty sure it was phenolic cage. I was running 20:1 castor so there was a heap of oil there. I had been thinking it was a bit rumbley on the dyno at lower rpm, but that was just the rebalancing & didn't notice any tingles at higher rpm, but the acetyl inserts must be doing their job more efficiently than I thought.

[husaberg]

yup. can't remember what the bearing was but pretty sure it was phenolic cage. I was running 20:1 castor so there was a heap of oil there. I had been thinking it was a bit rumbley on the dyno at lower rpm, but that was just the rebalancing & didn't notice any tingles at higher rpm, but the acetyl inserts must be doing their job more efficiently than I thought.

I guess the Mag side doesn't have the same support as the drive side?

[F5 Dave]

and its not in a constant oil bath like the Gbox side. a couple of hundie would get me some microblue ceramics, but I'm a bit shy of that on top of other costs I might find (+ I'd set some money aside for an igni for the 50 by selling stuff, & don't want to let go of that yet). + I'm not sure they do C3 or 4s, not clear on their site.

[speedpro]

You have some odd shit happening with that engine. Normal C3 & C4 bearings should be fine. Thinking back to that clutch problem you had at Tokoroa I wonder if there is a connection. I always thought MB cranks were pretty good, way better than Suzuki cranks anyway.

[Grumph]

Odd shit indeed - I was frankly surprised at the amount of movement on the motor mounts. IMO if you've got to turn it into a Norton Commando (isolastics) to make it rideable I'd have another look at the balance factor..When it can shake the plug loose and back off the head bolts too, it ain't right.

Another point must be crank truth...Did you check the crank between centers when it came back from, I assume, the local kart shop ?

[F5 Dave]

Std RS have a rubber mount system at the front. The mounting system on an MB is a bit of a drag as the front mount is virtually unusable. Everyone I know who has used it except Mike has had the cases break there. But I've repositioned the mounts at the back so they are closer together as it fits in the RS frame like that & no other acceptable way (with a decent size carb).

I'd used RG rubber mounts but the engine did move a bit too much so I remade them from acetyl & there is a mount at the head, but that is able to move sideways slightly (urethane washer either side & R-clipped nut) so it doesn't twist the barrel. It was quite sturdy. But there is definitely more movement now so the Acetyl has worn pretty quickly.

There was sod all vibration as the revs got up from a riders point of view & I hate vibration, I remember riding DaveDs MB & hated the vibes.

Pulled the bottom apart & actually the mains don't look poked. They have quite a bit of clearance & with a broken pin allow a bit of rock. So that kind of blows that theory. It was over-revving for quite some period every lap. I figured the revs themselves would be under the limit, but I guess the deto was taking its toll.

When I tightened the head down I should have lifted it, noticed the torn o-ring & replaced it. Ideally unstuck the stuck ring & thrown in the spare, but time was tight & I just wanted to see if it ran.

I'd had the crank rechecked when last apart & Kart guy was quite happy with how straight MikeC had made it.

oh yeah I found the Quick shifter sensor wires melted (against the pipe I guess) so that explains the erratic performance there & subsequent failure in race 1. Never did it without the fairing.

[F5 Dave]

So I hands the sorry parts to Mike & while we're talking I say the scribe line on the webs scared me as I though it was a crack; game over for those, but then with a wipe it was a scribe line, phew.

So he says yeah it was lining up where the stepped pin was . . . oh dear, the line on the pin is about 30* out. Its moved, probably the most when it twisted the pin break off, but clearly it could have moved a little causing the vibration that undid everything & possibly flogged the Acetyl mounts out. Obviously running it at those sort of revs for any time was going to end badly.

Next time a spot of weld.

[husaberg]

Well i am confused......... was it rebalanced for the offset pin. Also how long did that offset pin last.

[F5 Dave]

It was rebalanced when I destroked it using Speedpro's suggestion, obviously I run considerably higher revs than a roadbike & no balance shaft (that's where the inlet is now for case reed). When we destroked it we used a bigger pin & offset where it enters the web. Of course that weakens the pin but we put on as much radius as pos anticipating this & at its thinnest point (the bit in the web) it is the same thickness as a std MB. The size for the interface into the web was based on the std MB pin measured very carefully.

But I don't think the offset grinding of the pin was at fault, of course I don't know. About a year with this setup.

It was not a full pin, it had a drill centre. Perhaps a solid centre may be a stronger opition, but you won't get much added strength for rotational stress.

[Grumph]

It was rebalanced when I destroked it using Speedpro's suggestion, obviously I run considerably higher revs than a roadbike & no balance shaft (that's where the inlet is now for case reed). When we destroked it we used a bigger pin & offset where it enters the web. Of course that weakens the pin but we put on as much radius as pos anticipating this & at its thinnest point (the bit in the web) it is the same thickness as a std MB. The size for the interface into the web was based on the std MB pin measured very carefully.

But I don't think the offset grinding of the pin was at fault, of course I don't know. About a year with this setup.

It was not a full pin, it had a drill centre. Perhaps a solid centre may be a stronger opition, but you won't get much added strength for rotational stress.

Depends where it broke...I've noticed that a lot of aftermarket pins don't have a particularly good finish on the inner bore. When i make a pin - and i've made a few....I bore and then hone to a fine finish. I've always assumed that any marks on the ID could be stress raisers.
The offset grinding may or may not be the problem - it's hard to avoid getting the radius grind a tad too hot...

Gizza pic, Dave - forensic engineering is fun - when it's someone else's motor....

[koba]

Gizza pic, Dave - forensic engineering is fun - when it's someone else's motor....

So true!

Oh gosh, so true!