I've been noticing the belt has been slipping worse and worse lately. I took the cover off to find a film of oil inside. I'm am not familiar with belt driven systems. Can anyone provide any assistance? Thanks

 

Can anyone help? I know there a lot of threads on slipping belts, but never heard of oil inside. I'm guessing it's a seal on the engine output shaft???

 

Sounds like the R/H Seal is Knackered on the outputshaft from the clutch to the drive belt faces. I Have replaced a cpl. of these on 500's with only a cpl of thousands miles on them. Roughly takes about hour or 2 depending on How mucky the bike is and Your ability.