hey guys i need to pick you brains for a bit. im thinking about purchasing a used joyner JNSZ650DL. its got 160 miles on it, runs great, and not a leak in site. its been sitting in the sun for some time, but all that looks like that needs to be changed is the air intake hose. is it a deal for $4,500? and also i noticed it only goes about 50mph, if i get a new air intake and exhaust; how much faster will it go. or am i going to have to buy a turbo kit for a big change? what do you guys think?