Jackpiner bottom ends

[Mickey Sergeant]

What years if any are compatible with a 73 bottom end

thanks

[skiracer]

I would think up to and including 1979......

1976 MC 5 Original Owner
1976 Penton 175 XC

[Mickey Sergeant]

Maybe I didn't ask the right Question. What I wanted to know is if like the clutches are interchangeable,shift forks and tranny parts are the same for other years. Or are they year specific. Did I already get the right answer I was looking for?

[Larry Perkins]

I believe 1972-1976 will interchange but it all changed in 1977 with a new design.  The 72 and 73 are black motors and the outer cases are a bit different but interchange.  All from memory but believe this all to be correct.

Larry P

[ALB]

clutch plates are all interchangeable from 1972 thru 1978.

72-73 (black motor) shift cams and forks are the same for those 2 years.
74-78 (silver motor) shift drums and forks are the same and are also the same for the 250s and 400s.

Alan Buehner

[G Ellis]

Give me a call ,I can help you out. 217 260 0237

[Rain Man]

72-73  had the 12mm kicker shaft. They went to a 14mm in 74-?