Bike's in the shop right now to have the case replaced and the Tech. (not from a Yamaha dealer but reputable) looked over some other components and suggest replacing the following parts: my crankshaft assembly because of some signs of wear and tear, cylinder has straight, vertical scratches in it but I can't feel them with my fingernail (but visible) and I don't notice any lack of power and doesn't blow any smoke, primary drive gear showing signs of wear. Bike is a 05 450 with 70 hours on it, oil change every 5 hrs, air filter cleaned every ride, synthetic oil (Valvoline mx4t), Scott's oil filter, never been raced/rec. rider. Is it abnormal to need to replace these items when the case is split opened even if it's in spec? I need to find out exactly what wear and tear they are referring to I guess? Tough question I guess but just wanted some input on how far to go with these additional parts about $700 worth? If the wear and tear is in spec then I think I should leave it but I think the parts inside the case are tougher to replace later. I also don't want anything to fail if I opt to not have them replaced now. Kinda like $700 now or $2500 later. I hear alot about people getting alot more hours out of their bikes before replacing all this stuff. Am I doing something wrong? A money decision I guess?