81 kz1000M bottom end compatability

Good evening all,

I read a lot but don't post a lot

In the past year or so i've gotten hooked on the old KZ's! I'm deep in a 82 kz1000 build and wont have it ready for a whilllllle. Recently picked up a 76 kz650 but not sure if I'm going to hang on to it. I'm looking for a rider for this year and have the opportunity to get (possibly) a good deal on a 81 kz1000 M in a ltd frame, problem is it supposedly has an issue falling out of 2nd gear. I'm too deep in another project to take on tranny problems and aint' too keen on paying a lot to have a tranny rebuilt.

Does anybody have any idea of bottom ends that would bolt on to the 81 kz1000 M motor?

Thanks!

Im guessing any 1000j motor through 90s,possibly 1100s also

Some interesting reading from Ape Race parts:
www.aperaceparts.com/transmissions.html
www.aperaceparts.com/tech/techkz1000.html

Thanks for the help guys. Deciding to go against it. Can't get into Tranny right now!
Bike was real nice though