Transmission Selector Shaft Drum Getting Stuck Between Gears (72 CB350)

[Scotty]

Hello all, so my riding season ended with my bike getting stuck in 1st gear, couldn't even get it into neutral, but the shift lever spindle was still rotating normally.
Finally had some time to look into it this weekend by pulling off the right cover and clutch assembly.

The change pawl appears pretty worn and it's not always fully turning the drum, it sometimes pops out of position and moving the shift lever up or down won't engage with the drum pins. I'm guessing this is how it was when I got stuck in 1st.
However, even when turning the drum using the screw on the end of it (and spinning the rear tire at the same time), it still doesn't always turn and gets stuck in certain positions. Like I won't be able to get it into 2nd but then if I mess around with everything for a bit it will all of sudden go back to normal.
Also, the selector drum has a lot of axial play, more than a mm at times, is this normal?
I can't quite figure out what is wrong, I'm really hoping it's all external so I don't have to pull the engine.

Pic of the worn pawl, does this look okay or is it too worn?


Any advice appreciated, thanks!

 

[LongDistanceRider]

The pawl does show some wear but overall it's fine.
Try removing the neutral detent bolt on top of the case and see if the shifting gets better/correct.

 

[Scotty]

@LongDistanceRider I have that removed already, it didn’t make any difference.

 

[fxray]

Hello all, so my riding season ended with my bike getting stuck in 1st gear, couldn't even get it into neutral, but the shift lever spindle was still rotating normally.

Like I won't be able to get it into 2nd but then if I mess around with everything for a bit it will all of sudden go back to normal.

Also, the selector drum has a lot of axial play, more than a mm at times, is this normal?

The pawl does show some wear but overall it's fine.
Try removing the neutral detent bolt on top of the case and see if the shifting gets better/correct.

Scotty said: I have that removed already, it didn’t make any difference.

If you have the neutral detent bolt removed entirely, try putting it back in and see if your lateral movement of the shift drum is reduced. The neutral detent bolt not only has the spring-loaded ball to snap into the partial hole in the drum for neutral position, the end of the detent bolt acts as a locating guide in the wide groove on the shifter drum.



When you reinstall the detent bolt, run it all the way down to where it is slightly snug, then unscrew it one turn. See how that works out.

When I first got my SL350 K0 basket case put together and back on the road, I had a terrible problem shifting in the lower gears, first, neutral, second and often even third. I filed some stock off the end of the detent bolt and all the problems went away. It shifts great now, and it is easy to find neutral. The end of the detent bolt had been rubbing the bottom of the groove on the shift drum and restricting its movement.

Be careful with the lock tab washer for the detent bolt. I think these are NLA and I couldn't find a new one available to order. Maybe someone on here knows a source?