Modern Vespa

Hi i'm going to fit a PM exhaust to my 125 and was wondering if re jetting is necessary? PM says no, but i find that hard to believe. I have tried searching the web, this forum and other forums but haven't been able to find a definite answer.

could anyone on here clear things up for me?

cheers

Which 125cc bike are we talking about?

hi

it's not a Vespa, but a Runner vx125, so it's the same motor as the GT.
dunno if you guys won't answer my question as it's a hair-dryer, but this seems like a busy forum so i thought I should ask you guys.

cheers.

Well, I don't ride a Vespa. I like this site for overall mechanic info though.

I absolutely had to rejet after putting on a performance pipe.
And honestly, its been a lot of hassle. If you are staying in the same elev. it will be fine.

I have to go in and unclog mine. Mine is jet for 2,200 elev. but I'm traveling. It runs lean here and there and I just keep an eye on the plug.

I'm glad I have the pipe. But I didn't change my roller weights and the other day when I looked they were actually going flat on one side.
No diggity!

You need to make accommodations for adding the pipe. My air filter also got dirty faster and it is stock.

Cool.

thanks mate.
so upping the main by a few points is wise then.
what kind of jets does the 125 Leader LC take? will my 5mm delly jets or my hex keihin jets work or du i have to go out shopping?

and what size should I get?

cheers