Top End

[markmarino]

I have had my 2002 Rm 125 for 2 years and I notice a drop in power but not in speed, I think it is the Rings! I do not have a lot of money and I am wondering if I can just replace the rings and gasket kit but not the Piston. any thoughts?

[Spikester]

Yes you can.

[racerfty]

you can, but 125s the bike is normally at high rpm, and the exhaust side of the piston is subject to lots of heat, this could fail if the piston is reused, best to start of with new, but if cash is a problem, and the bike still runs, i would save until i could get a complete top end kit and do it right. it will save you down the road.

[markmarino]

I will replace the whole top end when I can; Makes sense

[kgibson181]

It's completely fine to replace the ring only usually a ring every 25 hours and a piston every 50 keeps eveything at full power

[MXtras]

I will usually put about 4 rings on a piston before the piston gets replaced. It's not at all uncommon. It does depend on the condition of the piston, of course.

Scott