looking into these years for a friend (i believe there are two different models within those years, yes? sorry im a yamaha guy). any years he should stay away from or focus more on? problems to lookout/check for before he buys? anything noticeable on the pre-buy check or ride besides the basic things to look for? i read something about a weak trans? is that like a full transmission overhaul to fix or a few bits and pieces and its golden? street use only for now, considering track late next season.