Motorcycle Repair: 1970 CT90K2

Question
Why is the sub gearbox popping out of low range under heavy load (going up steep hills)I have looked around but can only find info on carb & wiring so if you can help thank you in advance.

Answer

SUB TRANSMISSION   Hello Peggy,

Most probably, the shift-fork lock spring and ball (9,8,22 in picture) are stuck or rusted and fail to lock and secure the "low" position. And that's if everything is correctly in place. I've seen it many times, someone taking it apart and then put it back all wrong.

You have to remove the sub-trans cover (four #3 Phillips screws) check everything for visible defects and reassemble.

You can always, take pictures of everything, get back to me with them and I could help you more effectively.

Best Regards,
Lazaros.