On a Tall GRiSO, while backing off throttle it sounds real loud like the flywheel ring gear rubbing on a tire. Noise is font side of trans, so, try to catch it before damage is done. I figure it will be a clutch seen as I have fixed them coming apart and not a 6 speed yet.
This Stelvio goes like stink and he rides it to the max, 40K mi. Not what the owner needed to happen but it is a service time for his bike before he goes to Canada again.