The mods have nothing to do with the clutch he is describing. I found the R1 clutch was no different from the many other Yamahas I have owned. As someone stated above, the cable might have been removed and not adjusted properly. You will fix this down by the clutch plates, not at the lever. These R1 clutches are great and mine was not sensitive at all. If its engaging almost all the way out it is out of adjustment or the previous owner was a wheelie freak and blew through the clutch. Also check your fork seals if he was busting wheelies.