hi could anyone help me with a problem with my mates bike, its a 2005 250 cc sherco, sometimes when he starts it it runs in reverse?!! engine runs normal but when put in gear it runs backwards! also when its warmed up then stopped it is really hard to start until it cools. anyone know whats wrong?

sheared or partially sheared woodruff key incorrect timing or a faulty stator there is guide to help here http://www.sherco-moto.com/wayne_corner.html

Some one should write a thesis on this and get a PhD, there's plenty of research material there.