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2002 CR250 Jetting Question

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I have a bone stock 2002 CR250 with very low hours (30-40 hours?), my uncle bought it new and lets just say "he don't ride much".  He tipped over and dented his stock pipe and he went and bought an FMF gnarly pipe and Turbine Core 2 silencer.  He asked me to install it but I am pretty sure I will need to change the jets as well.  The bike runs good with stock jetting and stock pipe, so I just need to adjust the jetting for the new exhaust configuration, the temps and elevation are all going to be the same as before, my uncle does not go very far.  So what do I do, go up one or two sizes on the jets?  Both jets or just the main?

 

I have not owned a 2 stroke in 14 years so I don't remember the "rule of thumb" on this one.  Any help would be appreciated.  

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Should be fine with what he had in it. That pipe isn't really going to change things.

I think fmf has a recommended jetting chart (based of stock jetting). See what they recommend compared to stock & change your uncle's jetting the same amount they changed the stock jetting. If they went up 2 sizes, go up 2 sizes from what your uncle had, ect.

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So I called FMF and they provided the following suggestion:

 

Main 380

Pilot 32.5

Stock needle with the clip at the 3rd position from the top

AF screw is 1.5 turns out

 

I don't know what jets this bike has (stock) but I am going to tear into it this weekend.  I will update after, thanks to KPRacing for the response.

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