Hi i have a rxp 2004 with 70hr on clock i notice that thier is a little smoke coming out of the exhuast, not a lot just a little....

Any ideas on what this may be? some one has said could be valves etc, she run fine mo lagging on top end lost???

Is this a expensive thing to go wrong on what ever it is???? and where is the best place to get spares from i live in the uk