125 pistons

[Matt_H]

Soon I should be doing the top end in my kx125 and am currently not happy with what I am using. I have tried stock and vertex pistons in my bike and I'm not happy with there performance. I was wondering what your input was. What are my other options? any thoughts at all would help me out alot.

Matt

 

[CR-For-Ever]

Cant go wrong with a Weisco of course they are very sensitive when breakin in I would break it in very slowly and do it right, they have the tendacy to seize I use stock pistons very durable

 

[Durt Cycler]

What kind of performance are you trying to get out of a piston?

 

[SiCnTwIsTdYz]

well i heard stock will outlast any other piston,weisco,vetex,pro-x etc.... i did a top-enmd in my bike last march time for a new one but im going to go stock again i like the performace from it i seem to have no problem

 

[Matt_H]

I'm not trying to get get alot big performance gain I just want something that will last longer that 3 races. presently I put a stock one in since last year I had a ProX shatter on me. does anyone run vertex pistons? there made by pro circuit right?.

 

[Durt Cycler]

I am running a Vertex Race Series piston in my CR and am very impressed with its performance.

 

[marcusgunby]

The vertex are not made by PC, they are used std on some huskys and ktms, they often last a season in those bikes but i wouldnt go that far on a 125, i have a vertex in my Cr and replace it every 12hours at expert level.A novice should easily go 25hours between changes.PRO X are
made by the same manufacturer that provides the jap bikes so effectively you are saying std good but std is bad.If you are getting 3 rides on a piston i would look at
1,jetting-are you way too lean?
2 Airleak-again cuasing it to run lean.
3 dirt causing fast wear on piston.
4 ports not champhered properly causing ring wear
5 cylinder out of round or worn beyond spec.
6 too much compression causing detonation.
7 too little oil in you mix i use 32:1 on a 125.
Hope this helps.

 

[Matt_H]

Thanks for the help I have recently had problems with small amounts of dirt getting in but have since fixed. I went over your check list and very thing is good new cylinder first piston in it actually. And I think my jetting is way from lean(alittle on the fat side).

Matt