CRF250R STD bike jetting

Firstly i apoologise to anyone who is annoyed at me posting this Q twice, new to thumper talk and missed the jetting forum. :eek::eek:

I live iun the UK almost at sea level. My bike is as it was when i toke it off the show room floor.

I would like to see what difference removing the screen from my airfilter and jetting the bike correctly will make. Im no good at jetting and generally dont mess with it for fear of destroying my bike.

JD, you seem to have all the answers and hope you can help me with this. Im racing on sunday (off road event) and if you get a chance to respond to me, I will make the changes for then.

Thanks :D:D:D

I was told today by a bike shop to use a 178 main. any opinions? seems a bit large

in my findings,eliminating the back fire screen needs one size bigger main jet on a crf.

however,most stock main jets come on the rich side in most conditions.

test ride and determine if you need to make any changes.chances are its fine.

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