02 Kx125 Head work

[mxbrian199]

So i bought the bike running rich with a FMF Fatty Pipe and Shorty Silencer. I Got a brand new Phathead for it and its running perfect. My only complant is its over reving way to fast(i race). Its got the K12 dome in it wich is slightly over stock but even for a 125 its reving out to 4th gear in short straight. Anybody have this problem or know some solution other than to shift gears :/

 

[Rich Rohrich]

It sounds like the gearing is too short for the tracks you are riding. Checking the gearing you have on the bike and comparing it to stock would be a logical place to start.

 

[mxbrian199]

yea its time for new sprockets anyway guess thats a start. but the thing is it just started after i took the stock head off and put this one on??? its a 02 anyway me and my dad are doing a topend plastic all around sprockets and i hope i can get rid of these lipless rims