While fitting new front sprocket today i noticed all the teeth on the output shaft where worn down about 25%, anybody had to replace this shaft, do you think an idiot like me could do it as i doubt it's worth putting into a shop to get it done and i suppose you have to learn some time. Thanks for any input.

 

Yes, you have to split the engine cases to get access to the countershaft. Not a simple task and requires some special tools or ingenuity to get it apart. Pics of the worn spot will help with suggestions.