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CR85 Jetting question

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Ok so I just got a 2004 CR85 with a 07 engine in it, it still has the 04 carb. The carb changed for the 06 to the flat side.

My question is where should I go with the jetting, I understand the 07 engine has an engine design change but I cant jet to the 07 specs because it still has the 04 carb.

What I have now;

Elevation 926'

2007 engine compression is 155#

Bills pipe and silencer

VF3 Reeds

Main 138

Pilot 42

Clip #2 position

The 04 Pro circuit recommended is 122, 52, #2 which seems very different from what I have, which is why I'm asking. My numbers are closer to the 07.

07 Jetting, 142, 45, #3

Are the flat slide #s that much different? Should I jet to the 04 carb or the 07 engine? Are there any jetting guides for the CR85 like there is for the YZ250 in the Yamaha 2Stroke page.

Haven't had time to do plug chops yet but will in the next few days, I'm repacking the silencer first.

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There is also a BR7es plug in it.

My plan is to put the carb as close to stock specs as I can with my jets (PC Recommended) and BR9ES plug and start jetting from there.

So a 122mj, 50pj, clip #2, BR9ES

Its a big jump on both the Main and pilot, but I think they are so far off in the opposite direction they are compensating for each other.

It feels flat up top and breaks up off the bottom.

Anybody see anything really wrong before I give it a go?


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Alright here is a few plug chop pics. Jetting is 122 50 #2, alt 929', temp is 75 , Humidity 29% BR9ES.

Its breaking up with low throttle, but pulls stronger when wide open. I am only able to pull each throttle position on load for about 5 sec which may not be long enough for a plug reading but here is what I have. Its hard to get a picture of the mixture ring, the WOT looks darker then the 1/4 throttle.

First is 1/4 throttle



Next is WOT,



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