Am using the Motul semi synthetic 10/40. Plenty of people running that with the GSXR's and no issues. It's a very high quality oil. Can't imagine having an issue with that. Anyone else experience an oil issue with their clutch? My guess is that their is a clearance issue and is more noticeable when hot due to expansion. Or possibly an issue with the clutch drum or components. Perhaps a lack of lubrication at the clutch drum? Not a common issue as even the lousy service writer said that they don't see issues with clutches on these or the GSXR's. That's kinda of a giveaway that this is not a normal issue and that something has happened. Looking back, shifting has gotten a bit harder. Not as silky smooth as it was. This certainly shifts softer, smother than my other bikes. Although not at the moment.
2018 Suzuki GSXS 1000F
2007 Yamaha FJR 1300