2002 Yamaha V Star Classic "2003 650 wont" Questions

...2003 yamaha vstar 650. When it runs it back-firers spits and sputters then cuts off. then it runs great for a while then does the same thing. I took it to a machanic, it ran fine and it did it all ...

wont go ...can feeel the switching of the gears in the foot peg and the clutch cable is connected this is on a yamaha vstar 650 Your hub gear spline may be toast. You will have to remove the rear tire

650 vstar. I started it up and took it for a test drive and pulled it into my garage. My room mate was out there for quite some time checking out the bike. No idea what he did, but the bike wont start