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My notes list stock jetting for an 05 as:

40 Pilot, NCVT 3rd, 130 Main

When I bought my 05 it had:

40 P, unknown needle, 148 M. Bike had R header, Yosh muffler,  and 6 1" holes in the top of the airbox.

I'm now using stock exhaust and JD jetting; 42P, red needle 5th, 158M. JD includes a blue needle for cold temps.

Mine runs very good but is a bit rich during throttle roll ons, prob about 1/8 throttle. Substituting a 3/4" thick ring for the muffler insert fixed that.

Is your 68P a typo?


 

Edited by Chuck.

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On 1/14/2018 at 10:47 PM, Chuck. said:

My notes list stock jetting for an 05 as:

40 Pilot, NCVT 3rd, 130 Main

When I bought my 05 it had:

40 P, unknown needle, 148 M. Bike had R header, Yosh muffler,  and 6 1" holes in the top of the airbox.

I'm now using stock exhaust and JD jetting; 42P, red needle 5th, 158M. JD includes a blue needle for cold temps.

Mine runs very good but is a bit rich during throttle roll ons, prob about 1/8 throttle. Substituting a 3/4" thick ring for the muffler insert fixed that.

Is your 68P a typo?


 

68 Pilot is not a typo, what would be you recommendation for jets? a 42 pilot and maybe keep the main for now and adjust further later?

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First make sure you are using Genuine Keihin jets,

no need to add more variables by mixing aftermarket somewhat equivalents.

 

A #42 pilot jet is sufficient for about 95% of all CRF250X applications.

 

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I recommend at least going back to jetting that is stock, or somewhat richer, but not richer than what I'm using. Have said that the carb also needs to have correct float level and correctly adjusted accelerator pump.  I agree a 42 pilot is as rich as you need, and only use genuine Keihin parts. Jets are stocked by most Honda dealers and avail from Jets R Us. 

The FCR carb is used on most of the off road 4Ts and is complicated but proper adjustment makes them almost like EFI.  Lots of info in the Jetting forum.  And the 04-06 versions need careful adjustment of the accelerator circuit.
The FCR carb is also has a two piece body with gaskets that can be damaged by using carb cleaner. Until recently repair gaskets were not available so you had to buy a new carb.

I'm at sea level but my jetting works to 5000 feet.

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3 hours ago, Chuck. said:

I recommend at least going back to jetting that is stock, or somewhat richer, but not richer than what I'm using. Have said that the carb also needs to have correct float level and correctly adjusted accelerator pump.  I agree a 42 pilot is as rich as you need, and only use genuine Keihin parts. Jets are stocked by most Honda dealers and avail from Jets R Us. 

The FCR carb is used on most of the off road 4Ts and is complicated but proper adjustment makes them almost like EFI.  Lots of info in the Jetting forum.  And the 04-06 versions need careful adjustment of the accelerator circuit.
The FCR carb is also has a two piece body with gaskets that can be damaged by using carb cleaner. Until recently repair gaskets were not available so you had to buy a new carb.

I'm at sea level but my jetting works to 5000 feet.

Ok so i'm ordering a 42 pilot and what for a main? maybe a 140, 142, or 145?

what about the leak jet and anything else? do I have to worry about that stuff

Edited by allryder

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