ec125 -01 power valve issue?

[Neil E.]

Likely not, but it could start showing up there the most. At least do a compression test to see that it is in the ballpark. I'm not sure about the 125cc motor, but 150 psi would be good enough that it should run OK.

[Jakobi]

It could be a main seal as well (either pulling air through the flywheel side, or trans oil from the rhs).

Have you tried going a step richer on the needle? or a step leaner? What effect does it have on how the bike runs?

How did the piston skirt and cylinder look through the exhaust port? At least pulling the head you'll get an idea of how the bike has been running in terms of piston wash.

[Nicolas89]

Ive tried NOZI N1EG and N3EG. No noticable difference. I shall measure the compression

[Jakobi]

Originally Posted by Jakobi

It could be a main seal as well (either pulling air through the flywheel side, or trans oil from the rhs).

Have you tried going a step richer on the needle? or a step leaner? What effect does it have on how the bike runs?

How did the piston skirt and cylinder look through the exhaust port? At least pulling the head you'll get an idea of how the bike has been running in terms of piston wash.

Going huge on the main has showed a rich condition at WOT, but thats not what you're trying to do. When you tried all these different needles have you tried different positions?

What exactly is the bike doing? Have you pulled the choke to see if it helps or hinders?

I still don't think its jetting related, but would happily be proven wrong.

[Elvis74]

I bet there is something else wrong, like a gasket or so.

[Elvis74]

The Problem is that the carb also wears out. Get me new one, it's the easiest solution.

[Jakobi]

Over time the nozzle wears out (interface between carb body and needle). Not a replaceable part (on the PWKs) as far as I'm aware.

You should be able to pick one up for a reasonable price from someone whos gone the Lectron or APT direction, or you could consider that option yourself too.

[Nicolas89]

Okay. Then I will look for a new one. (Used) so again whats the difference between all the pwk's?

[Nicolas89]

Or maybe more important. Can I use any keihin pwk?
Is there any idea try to fix the old one? Maybe a new needle valve

[Elvis74]

a PWK is a PWK as fare as I know.
Make sure that you get thr right size, GasGas uses 38mm, KTM 36mm!
Maybe you ask Kelly from Motosportz, he has a special version of the Lectron carb for small engines.

Or you ask here http://www.keihin-na.com/ for the spare parts you need