www.partzilla.com/catalog/yamaha/motorcy...968/dt1/transmission

Gears 5 & 7--then 22 & 21 same gears. Just a bit of useless info haha.

Hi again, I thought it would be useful (at least for me) to summarise where we are - and hopefully move on to getting in the parts and rebuilding.

1) I have a DT1 shifter system, cam and forks
2) I have a 15t main (clutch) shaft (poss RT2)
3) I have a DT1/RT1 drive shaft (without the step)
4) I have a mix of gear ratios (1-5) 38/15 33/20 23/19 24/21 19/23 (mostly DT1 with RT2 first dunno what 2nd

Where I go from here I think will be determined by which drive shaft I can source to replace the busted one.

But I have a couple of questions.

You've mentioned large/small teeth gears - is the difference in height or width etc? I'd likt to be able to identify to make sure I'm matching right
Would the DT1 shift forks etc be 100% reliable on later gears, shafts etc


Many thanks
D

Blimey, i'd say your going to be teaching us. Coarse tooth gears of early type are obvious if you had the two sets to compare. Coarse style is just less teeth per circle. I'm wondering if it might be better to look on ebay for a complete RT2-3 trans with drum & selectors & all. That's if your cases have the hole for the extra selector shaft which i guess it must have. Good thing about yamaha is that so much is interchangeable through the model "70--"73.

Yamaha has service bulletins on the gears and what goes with what.  I think there might be some in back of 1971 DT1E service manual in tech library.