by Ferrous_Head » Mon Dec 31, 2018 4:29 pm
Probably not a broken shifter spring. Or even a stuck pawl. When that happens it will shift in one direction only. The gearbox ill shift down to first or up to 4th and then your stuck in that gear.
But shifting ears depends in gears being able to slide on the shafts. If the bike has been sitting that long they may not be free on the shafts to move.
But unless you pull it apart you'll never know for sure what the problem is.
There's no great magic in splitting the cases. There's enough help here and elsewhere to get through that job. If there's no serious damage inside you don't need to replace anything and the engine can go back together quite easily using existing shims.
There are no useful shims in the cam area. If it has shims behind the cams either place then under the dog bones or leave them out.
Used oil contains contaminants some of which are acidic and will attack some metals over time. I don't know if there are problems with these engines but it happens in some.
"I know only too well the evil that I propose, but my inclinations get the better of me."