Wild 300 Gearbox problems

[case-racing]

OK i had bad vibrations last time i rode so i pulled the magneto cover off to find a bolt had come off and gone around a few times and did small amount off damage to the cases, now i fixed that and thought all was good untill i went out again and now it is locked in gear and the vibrations are still there but not as bad, i'm thinking total stripdown and go through it all to check it out as i don't need this breaking down a couple off kays from home, any one have any suggestions on what to look for or what to do. , i love the bike and when it goes it goes hard but when it breaks its very frustrating.