TOPIC:

Mikaw wrote: I've seen that NOS 900 listed before a few months ago...

It's not unusual to advertise things for over a year in order to get rid of them. That motor needs a collector to justify spending that much moolah on a NOS engine. Not surprising he is shaking the CL nut tree hoping for a buyer with $7K to fall out with his wallet open.

hardrockminer wrote: The one in the basket is a Z1 engine. I can tell by the end of the cam covers and by the "903" on the barrels. My guess is it's from 1976, based on the carbs.

Nice complete basket case engine and carbs. Too bad it's so far, it would be sitting here now.

Mikaw wrote: I'm looking for a '76 KZ900 for my LTD, but so far only find empty cases.

Maybe these cases are close to the right number (although the price seems way high).

pittsburgh.craigslist.org/mpo/d/monongah...lete/7044067489.html

Sounds like a scam to me.
Steve

DOHC, thank you for the lead. I found a set of cases. . But with this post revived I'd like to ask about crankshafts. What years will fit in the '76 cases, I'm seeing ones but don't know about the tooth count. I've seen 15t and 17t. Is the cam sprocket on the crank? What affect would a different tooth count do.

You need a 15 tooth. Early 903 cranks look like this.

Early KZ 1000 crank would work but are heavier.

Steve

Thanks Steve. I found one like the first picture but the wrist pin area is rusted. Can that be honed out without causing a problem? What is a good price to pay for the crank

Mikaw wrote: I'm seeing ones but don't know about the tooth count. I've seen 15t and 17t. Is the cam sprocket on the crank? What affect would a different tooth count do.

Here is some crank info.

www.kzrider.com/forum/2-engine/23292-crankshaft-cam-chain-teeth

Mikaw wrote: Thanks Steve. I found one like the first picture but the wrist pin area is rusted. Can that be honed out without causing a problem? What is a good price to pay for the crank

I think I paid $50 plus shipping for the crank. I was watching three. I studied the pics very carefully and knew it was a crap shoot. I figured with what I had and there was a bad bearing I could use parts off the one I had. I got lucky. I washed it really well in diesel before I installed it.
Steve

Mikaw wrote: What affect would a different tooth count do.

If the cam sprockets are not changed to match, the effect would be disastrous. The cam sprockets must have exactly twice the number of teeth as the crank sprocket, otherwise, with every rotation of the crank, the cam timing would get farther and farther off until valves began bagging into pistons, then valve heads breaking off, then BANG!

TexasKZ wrote:

Mikaw wrote: What affect would a different tooth count do.

If the cam sprockets are not changed to match, the effect would be disastrous. BANG!

Thank you Texas KZ.... BANG! is not good.... Are all 900 cranks 15T? At some day in the future I'd like to do a big bore kit. nothing bigger than 1075. I have read that the stock cams are good low end power with the right carbs and a modest piston size increase. Will the lighter "porkchop" 900 Crank be good for a street motor of the design I've purposed? It will not be ridden hard every ride, but want the extra power there on the odd occasion arises...

My next step will be a 1075 with larger cams. Meanwhile with my 903 crank, Wiseco 1015 pistons, Andrews 1X cams and 33mm Mik's I RIDE THE PISS OUT OF IT with no complaints from the bike.
Steve