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Should i go up to a 45 pilot jet ?

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2008 CRF250R, Runs amazing in cold or hot weather BUT starting in cold weather is annoying... It takes at least 10 kicks while i can start on 1-4 kicks in hotter weather.

Hotter weather to me is 75F / 24C to 78F / 26C

Colder weather - 50F / 10C to 60F / 15C

I'm close to sea level (Ride around 600- 700ft)

My jetting-

Pilot - 42

main - 178

leak - 70

So do i just bump up my pilot ? Is it worth trying ?

Thanks for any help

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If you use your choke always, and it is ineffective in cold weather, you need a larger POWER JET, the jet that feeds the choke circuit.

But before you do that, try 4 twists of the throttle, choke on, throttle closed, then kick.

Have you adjusted your valves lately? Most common symptom is harder starting.

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Good advice from Krannie.

It doesn't hurt anything, after you've tried the things on his list, to put in a 45. It's not like you have to weld it in and it's a permanent choice.

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So do i just bump up my pilot ? Is it worth trying ?

Yes. Assuming a 250r is jetted the same as a 250x on the pilot, a 42 is too lean near sea level, IMHO. I'm running a 45 in my 250X @ ~500ft and similar temps. I jet the pilot for snappy throttle response right off idle.

JayC

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Yeah im at 2.5 turns on the fuel screw with the 42, I just put a 45 in today so i will have to see on Saturday if it works...

Thanks for the replys

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When its cold you need to twist the throttle anywhere from 3 to 6 times to prime the engine with gas. Then like Krannie said choke on and dont touch the throttle. Use solid kicks from TDC. If it starts then dies right away twist the throttle a couple of times and kick it again.

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Thanks for the help guys,

Just for any people viewing the thread wondering if the 45 helped...

Yeah it sure did, It was cold today and started way easier than with the 42 pilot in there... Still needs a little bit of adjustment on the fuel screw but did good at 2 turns out...

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