Hey everyone, Im new to the forum but i have been lurking here for a while, great stuff.
Anyways, a few months back I ditched my 07 yz250f 4 stroke and picked up an 05 yz125. Relatively new to these 2 stroke beasts but i couldn't be happier with my decision. The only thing is I noticed alot of stuttering and cutoff in higher rpms. It just doesnt sing like it should. It idles perfect, for about 8 seconds and the mid range power is fine though. I am in the process of doing the top end and could use some insight onto where to go from here jetting wise. When i opened the powervalve top it was packed full of gunk unburned oil. Im almost positive its running too rich. The plug is black and wet and the piston doesnt look to great, and i think it was a contributing factor to the poor operation in higher rpms.
I am looking for some advice on where to go from here, runing 40:1 maxima K2, jetting is stock, 410 main, 40 pilot, 4th position clip. Along with a new top end, the silencer is going to be repacked, reeds cleaned and checked, powervalve cleaned so i have a fresh base to jet off of.
also, i notcied some pretty bad blow by on the piston, the ring was out of spec aswell.
So what do you guys think? Rich? what to change first? any help would be greatly appreciated!
And heres the bike just for some eyecandy