I have a 2010 UC with 15000 happy miles on it . So far no trouble, but I don't run her real hard by slammin the gears. Just normal riding for a 67 year young man. Like to play with her but only to a point. Shes may last ride so I haveto take care of her and she me.
Think I may switch to the redline shockproof heavy, if for no other reasons that it won't hurt and it's cheap & easy -- and it might help. If Glider's right about the way the 6 speeds are being built -- there's an aftermarket opportunity for someone to jump on; putting together a build kit with good solid parts in place of the substandard junk -- if that's really what they're using. I wanted a 6 speed, but my warranty is over . . . so I'll hope it holds together.
Redline shockproof heavy is a great lube for the trans as well as Spectro Platinum. Either will give you good service from the Harley trans.being top of the line gear lubes.
Harley 6 speeds are not the best trans around. They have a number of weak areas and if the bike is ridden hard, they will not give very good service before they let you down.
Weak trap doors that flex which allows the gear set to move in the case and plastic bearing retainers are just a few areas.