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Winter jetting?

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This is my first smoker and i love it but i live in Maine at sea level and have a 00 cr250 with pc pipe and power reeds it is way o lean and running hot.

so what do you guys run for jetting in the winter?

thanx

Donnie

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I,m no expert but I do knowyou can have two or more identical bikes and they will be jetted differently so you need to jet your bike to the way you ride.

This is how I jet:

bump up the main jet first 2 or three sizes - Hold it WOT for about 3-4 seconds in third going up a slight grade. if it takes it, go up one size until it stumbles, when it stumbles go down one size until it runs clean.

2nd - jet the needle with your type of riding and ride your normal pace for a 30 min (1/4 - 3/4 throttle range and check your plug insulator - should light tan

move clip up if rich and down if lean

3rd: SJ - start at 1.5 turns from seat and adjust for best throttle response

This is all assuming:

Float height is set correctly

No air leaks

Edited by gitenold

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This is my first smoker and i love it but i live in Maine at sea level and have a 00 cr250 with pc pipe and power reeds it is way o lean and running hot.

so what do you guys run for jetting in the winter?

thanx

Donnie

I've had good luck by going 2 sizes bigger on the main jet, and one clip postion richer on the needle for winter riding in MN. This has worked OK on several different bikes.

These are starting points - your bike might require more tuning.

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I also have basically the exact same thread going without any replies but my question is how do you know the type of riding you need to jet it for? Honestly, I do a bit of everything...Both slow and fast paced riding just depends on the day..

Also I know you're supposed to do the main before the needle to prevent top end damage but is it normal to go up 2 or 3 sizes at a time?? My bike is running excellent here in memphis at 50-60's stock jets 175/55/42 so I'm thinking maybe I should only go up 1 size....Still very new to jetting so I have no idea.

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I also have basically the exact same thread going without any replies but my question is how do you know the type of riding you need to jet it for? Honestly, I do a bit of everything...Both slow and fast paced riding just depends on the day..

Also I know you're supposed to do the main before the needle to prevent top end damage but is it normal to go up 2 or 3 sizes at a time?? My bike is running excellent here in memphis at 50-60's stock jets 175/55/42 so I'm thinking maybe I should only go up 1 size....Still very new to jetting so I have no idea.

Jet for your most aggressive riding

I just meant to go 2-3 sizes initially just in case your were way to lean, then go one size at a time.

when you get the main right, it makes a big difference in top end grunt

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Yea I'd like to add a thank you aswell my tuning chart only suggests one size up on main but we have real moderate weather and 300 ft above sea level

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I have used this chart for 2 years and it give you a great starting point. I run 32:1 and jet by this chart and I get zero spooge and the bike does not run hot (lean). Just an idea. It is for a 2000 CR 250.

2000CR250Jetting.jpg

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