Author Topic: Jetting from 80 deg to 20 deg weather (Read 2202 times)

pantera1975 · « **on:** December 06, 2013, 09:30:02 PM »

I have a trx 9 ESR motor in a ATC with a 39 mm Keihin carb. Is it common to have to raise up the needle or use a richer one. How much should I start with changing the slow and main jet?

supernutt · « **Reply #1 on:** December 06, 2013, 09:42:32 PM »

I usually raise the needle 1 clip and up the main jet. Ran a 192 this summer and currently running a 200 in freezing temps. I always figured 1 main size for every 20 degrees in temp change. Never really mess with the pilot...Just the air screw a little..

rk88r · « **Reply #2 on:** December 07, 2013, 10:34:59 AM »

I do about the same as Supernutt. Just raise the needle a clip. I did buy a ecg to experiment with this winter, in the past I've run a dej one up. It's so damn cold now the R is staying in.

Bigred · « **Reply #3 on:** December 07, 2013, 06:24:24 PM »

I just kick it over and run it lol

The_Steve_Man · « **Reply #4 on:** December 07, 2013, 06:48:17 PM »

It was 16 here today. No 2 stoke riding today. But very good information

supernutt · « **Reply #5 on:** December 07, 2013, 06:57:46 PM »

I had about 22 degrees and it was awesome!! Went out for a hour ride. No snow and frozen ground. Cant tear anything up and quad really goes on frozen soil.