Well, the guy I had looking at my crankshaft handed it back and said he wouldn't touch it. He gave me the number for Falicon and I called them. They said $300+ for labor. Apearently these cranks are difficult to get dialed in again. We also agreed one of the crank pins is probably damaged and can't be repaired. So it looks like I will be buying a new crankshaft and sending this one off to ebay (maybe somebody with more gumption has a use for it). But, new cranks are out of stock and not due for another month. I guess that give me more time to work on the rest of the motor.

I started getting in my new Rothmans bodywork. Looks great and comes with stickers and paint.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Hard luck mate, though at least with a new one you have no worries about how good a job they've done on the rebuild, and now you can look after it you know it'll be good for years.
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

What's the source for the bodywork?

Wow, I have 2 extra crankshafts here I really need to have checked, though they appear to be in excellent condition.

Interested? I also have the crank seals you would need still in the packages. Heck, I even have a set of engine cases you could put this crank in and have an entire spare set you would just need to put your tranny in!
_________________
Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
MY BIKE PICS

I'm interetested, but they need to be perfect.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Rebuilding the cranks is not exactly rocket science. It's finding the necessary replacement parts. That's the tricky bit.

I cheated an made a jig for pressing the centre halves together. The outer crank wheels are just normal procedure. Press it on as close as possible then tickle it true with a couple of gentle taps with a bloody great copper mallet

Set big end clearance at 0.55~0.6mm.

Kevin Murray couldn't do it? He told me that the NSR crank is pretty easy(for him) to do.
_________________
MC21 300R w/SE bits, Rossi 2001
MC28SE Silhouette Repsol

That name doesn't ring a bell. In any event, one of the crank pins is probably damaged and not cost effective to repair.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

You could in that case use it as an excuse to "stroke" it!
_________________
Andy.
NSR-WORLD.COM

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Andy wrote:You could in that case use it as an excuse to "stroke" it!

Explain.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Lay a cosy blanket on your knees whilst sitting in your favourite chair. Lower the crank gently on the blanket (ignition side to the left) and using a firm hand stroke it from left to right as if it were your granny's Yorkshire Terrier.

I think that's how it's done....Andy?

Matt@TYGA wrote:Lay a cosy blanket on your knees whilst sitting in your favourite chair. Lower the crank gently on the blanket (ignition side to the left) and using a firm hand stroke it from left to right as if it were your granny's Yorkshire Terrier.

That routine seems a bit familiar...
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Sorry, that was a bit silly.

Stroking the crank means to change the actual stroke (the offset) of the crank pin.

Generally you would make the offset larger. So on the NSR the stroke is 54.5mm, so the offset from centre is 54.5/2=27.25mm. Move this offset to say 28mm and you increase the stroke by double that. The stroke would be 56mm, so you could say you've 'stroked' it a mill and a half. This extra stroke gives the engine more capacity.

Normal NSR: 54mm x 54.5mm = 124.82cc
Stroked 1.5mm: 54 x 56 = 128.25cc

WOW!!

Stroking can be done an a couple of ways. Rebore the crank pin hole off centre at the desired offset and fit a larger pin. Or weld up the hole and rebore at the desired offset. The NSR could possibly be done by welding the crank pin and regrinding at the new offset, then welding and reboring the out crank wheel holes at the new offset.

You'll probably have to replace the conrod with a different length rod or you may have the piston hitting the crank. A longer rod reduces the crank angle through the stroke. Oh there's lots of things. Better off searching the net to find out more about it.

Try here: http://victorylibrary.com/mopar/rod-tech-c.htm

Thanks Matt. I know what stroking is... Just not sure how to go about it on the NSR. You can also grind the crank pin offset, but that would require a specail bearing, and you would likley need special rods to clear the case. But then you loose your rod ratio and you would likely need to re-port it because of the timing change. I don't think this really solves my problem.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm