RS125 Some problems :/

PioneerFX · 23 Feb 2015 at 20:14

Hi, long time lurker, first time poster in biker cafe.

In short i have 09 plate rs125 fp, 34mm carb. About a week ago i started having an issue with the bike, around 8000rpm (where valve should open and u feel it) it just doesnt. It'll rev a bit higher to about 9,500 but then it feels like im bouncing off the limiter. I did a quick plug check and seems fine, but i hadn't really been bothered by it because i just got my new bike, so the RS sat in the garage.

So now im looking to sell the RS, but of course i couldn't sell it knowing something is wrong with it. Where should i start to try and diagnose the problem? Or if anyone knows what it is, even better.

Thanks in advance.

wazza300 · 23 Feb 2015 at 20:34

does it have an electric servo power valve? theres a cable to it that you can adjust so that it kicks in at the right revs

its like a round disc that turns with two cables coming off it

tl45 · 23 Feb 2015 at 21:55

Some powervalves are prone to getting gummed up with exhaust gunge over time - wouldn't hurt having that checked out if it's more than just a cable adjustment issue.

atpbx · 24 Feb 2015 at 08:29

As has been said, the power valve is slugged up.

You need to clean it and lube the cables, don't forget, this is a moving part that is directly in line of all that unburnt 2 stroke oil and carbon being fired out of the cylinder, it's going to need cleaning once in a while.

leigh_boy · 24 Feb 2015 at 08:42

exactly as above, also a 34m carb is not factory on this , so might want to give it a clean up as well.

PioneerFX · 24 Feb 2015 at 10:24

thanks, gonna get stuck into it today. will let u know how it goes