Transmission sticking in 1.st

[jollyroger]

Dang, I have a couple of gearboxes that have a bit of slop in the 1st. and 2nd hub. This causes the things to stick in 1st. Had these things apart oh about 400 times now. Any ideas? I have tried a number of things. I build them all the same way but some just won't comply.

 

[ChrisS]

My ribcase did that as well. The cause was that the fork would slide the outer gear too far in the 1st direction to the point where the balls and springs would come out just enough to lock it in 1st.

Now I'm doing this from memory, but the solution is to add a washer on the rod to limit travel so this can't happen. It just floats on the rod and hasn't caused any problems.

I owe credit for this to the guy who sold me my current box. He had it happen to his daily driver after work one day. Just imagine driving home from work in Boston in 1st gear; I don't think he made any friends that day. Now he does it to his street car and his racer.

I hope this helps.

 

[jollyroger]

Yeah, I have figured that out. But I am really searching for the root cause. I have gone so far as to instll a shift rod out of a smooth case. this limits the movement. But with all new parts why does it do it? I just like to solve problems. I am beginning to think that the inner hub for 1 st gear is just flat worn out. Maybe the main shaft is worn. The inner hub seems to move too far forward allowing this to happen. There is a detent bullet in the hub that is supposed to keep this from happening. Go figure?

 

[ChrisS]

Sorry, I don't have dimensional data for the transmission.