340 Main too lean? '00 CR125

I'm using this:

http://www.procircuit.com/jettingspecs.htm#2000 (I have PC platinum pipe)

It calls for a 340 main. Everywhere else I look people are running 360's to 370's.

Am I reading the chart right? Does PC want you to lean out your main w/ their pipe? Seems backward to me.

Since the pipe flows better the engine will draw more fuel through the same size jet requiring you to lean the jetting for an ideal fuel/air ratio.:lol:

Ok. Think I've figured out jetting BUT I'm still getting spooge.

Running 340 main, 40 pilot, 2nd clip on stock needle, and air screw 2 turns out (using idle speed test). PC pipe & Ready Racing filter (clean). Yamalube 32:1.

Two things I'm noticing, I have an small exhaust leak out of the head and at the silencer joint. Will this affect jetting?

What's ur plug look like.shouldn't affected ur jetting,my old cr80 always leaked around there...

I'll do a plug test asap. Right now my motor is in 20 pieces.

Why is it in 20 peices?

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