Will I die if I disregard this crack?

I found two cracks in the engine as I was dissembling. What will happen if I just build the engine and ride it? Is it dangerous if I run it into the ground?

Well, your BALLS are pretty well protected by the battery and frame.

Might lose a foot at the ankle, but you could still procreate.....BUT after this question, it might be a good idea to keep your swimmers to yourself.

Yes; it is dangerous. Envision a catastrophic engine failure while traveling in traffic (especially on a highway) with cars and/or trucks directly behind you. Not healthy! Also, such a failure while running through a turn or other circumstances could lead to a stay in an emergency room (or worse). I would consider riding a bike with such a seriously cracked engine to be similar to playing Russian roulette. Ed

+2,3,4......Think of what it took to get that motor to that point, the two breaks you mention and the badly torn main output shaft bearing I saw in your other post. I suspect a real catastrophic event took place and I would put money on more damage existing you haven't even uncovered yet. I cannot imagine that 650 motors are that hard to find or that costly, certainly when compared to your wellbeing

1000...Well I just bought all the parts required to fix it. Bolts, Pistons, Boring, Gaskets, Frame painted, Tank painted, New Electrical. About 2000 dollars already spent. New engine from that guy in Florida is 4000. There a couple motors near me called Suters Speed Shop but I think he wants like 800-1000. I guess I didnt think about what would happen to the crack under pressure. If anyone knows of a mid engine (which is the rarest to come by as it has the serial number right?) let me know?

Search Craigs List for a complete (or not) bike, especially with no title just for the motor, you might have a little luck.....as you already have bought parts look for something that will give you a decent looking set of cases and still build your motor from scratch. Ebay may be a source just for a set of cases, they run well under $100

What years am I looking for? What bottom ends will work with what I got?

Check kz650.info forum,lots of parts floating around there.

...I have a 1000...Will they have those parts in the 650 forum?

Why not check here? There's bound to be someone that has good cases here, I am certain I have a goid set of 1000 cases but I believe those to be J model ones, might be able to find a set of early kz cases, if I have a good set (should only get a matching set PERiOD) I would send them for shipping cost

DobbinsCMA wrote: ...I have a 1000...Will they have those parts in the 650 forum?

Sorry thought you were talking about the 750.
Check with kz1006,hes a member on here for 900-1000 parts.

do you mean kz10006?