How can you tell a 4 speed from a 5 speed?

Slarsonroy · Post by **Slarsonroy** » Fri Aug 12, 2011 9:41 am

Ive got a couple 250cc motors and a 350cc motor that are disassembled and would like to know how to tell if its a 4 speed or 5 speed tranny? Serial numbers are suspect, so dont want to rely on that. At least one of the motors came out of a scrambler frame (1966?). Thanks

Rick · Post by **Rick** » Fri Aug 12, 2011 2:06 pm

As you're sitting on the bike, if the DM250 is stamped on the left crankcase half(the clutch side), it was built as a 5 speed, if the DM250 is on the right case, it was built as a 4 speed. The shifter box for a 5 speed has an extra peg- you may be able to feel how many clicks you have, but that would just identify the shifter box internals. The engines must not be completely disassembled or you could count the gears on each shaft.

Slarsonroy · Post by **Slarsonroy** » Fri Aug 12, 2011 2:28 pm

Like I said, the serial numbers and case numbers are suspect, but I do have them apart. Two sets of gears for each transmission. One shaft has 4 gears, the other shaft has 5 gears. I just want to make sure they are 5 speeds.

Rick · Post by **Rick** » Sat Aug 13, 2011 9:12 am

it's a constant mesh transmission- needs to have mating gears on both shafts, so 4 on one shaft and 5 on the other won't work

Slarsonroy · Post by **Slarsonroy** » Mon Aug 15, 2011 3:30 pm

Rick wrote:it's a constant mesh transmission- needs to have mating gears on both shafts, so 4 on one shaft and 5 on the other won't work

Thanks for pointing that out. I almost left one out with the set.