I am possibly getting this 1987 Yamaha YZ490. I don't know much about this model, is it a collectable bike? What do you think I should pay for it? The owner says the top end is new, the bottom end was not touched but no sign of shifting problems, new chain sprockets, tires, and everything powdercoated or replated. I think the bike looks pretty awesome, should I stay away from this one???? Thanks again, I always great great advice from this site!!!!