Jetting specs for '07 YZ125 PC pipe & Rad valve?

Joko
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Joko
Edited Date/Time 10/17/2013 5:33pm
Hi,
Can anyone share their jetting specs for a stock '07 YZ125 ... I'm switching to a Pro Circuit pipe & silencer with a Boyesen Rad Valve, at sea level, 60-75 deg F ?

Thanks !!
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captmoto
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captmoto 10/17/2013 9:52am
10/17/2013 9:52am
Go to PC website for their specs to start. What does Boysen say about jetting?
Joko
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Joko 10/17/2013 5:21pm
10/17/2013 5:21pm
captmoto wrote:
Go to PC website for their specs to start. What does Boysen say about jetting?
Well...
PC says keep the 410 stock mainjet, use a 35 pilot (stock =40) and move the clip from the 4th groove from top to third; jetting does not change with reed valve upgrades.

Boyesen says if the RAD valve is added and the stock pipe is used, drop the main to a 380 or 390. If the PC exhaust is used, go up to a 400 mainjet from there, since the PC exhaust needs more fuel.

JD jetting says jetting does not need to be changed when changing exhausts, since pipes only move the power around the powerband, depending on which pipe is used.

I guess I'll go with the PC jetting to start and keep an eye on the plug color and err on th.e rich side ...
Jakes Dad
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Jakes Dad 10/17/2013 5:33pm
10/17/2013 5:33pm
Leaner is usually the ticket, lean the main one and the needle one. Then learn WHY you need to making these changes. Take the time to read and re-read this a few times it will benefit your tuning abilities big time! http://www.strappe.com/plugs.html

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