Thanks for your videos. I have a 2003 KTM 125sx that I rebuilt the whole bike last year. The cylinder was done by Millenium technologies. I haven't ridden more than 80 hours and compression is barely 125psi. Do you think it may need a new piston and ring. I think it was like this from the day I did the top end. What other places can cause low compression? Thanks
80 is due for rings and piston. I would pull the cylinder and take a look. Those small bore 2 strokes take a beating in 80 hours. 125 psi is more than likely just wore rings.
