Cold Weather Starting?

11 replies to this topic
  • b-bike

Posted December 22, 2004 - 07:34 PM


In the typical winter weather around here (Oregon) the temp gets up to the mid 40's with the mornings droping to low to mid 30's. My bike has no poblem starting in the summer but not so in the winter.

Does you starting routine change for winter? If so... What is it?
Do you change you jetting for the colder weather? If so... What is it?


  • Butta

Posted December 22, 2004 - 07:39 PM


With drastic temperature changes, you may have to rejet. As the temperatures plummet, the air is more dense, and your engine is now subjected to a more lean condition. Try the pilot screw first, and if that doesn't fix it, replace the pilot jet. Anyone have anything else more in depth? I'm in Florida, and don't notice any huge differences, nothing that the pilot screw can' fix, anyway.

  • b-bike

Posted December 23, 2004 - 09:28 PM


Awe come on guys... What gives?? :cry:

There has got to be more of you guys that have overcome this cold weather start-up problem. Eather that or I have the only bike that acts like this??? :cry:


  • Bobby_Holeshot

Posted December 23, 2004 - 09:38 PM


I have a YZ400F that was really easy to start and restart when hot. But when the weather got cooler here in eastern WA. everything changed. I went from the std. #46 pilot jet to a #50 and now it starts on the 3rd or 4th kick when cold and 1st or 2nd when hot. You might need to raise the needle a little too. :cry:

  • grayracer513

Posted December 24, 2004 - 08:31 PM


"Really Cold" here is only about 40 by ride time. I usually just give it another couple of throttle twists for the extra prime, no problem. :cry:

  • Todd98YZ400F

Posted December 24, 2004 - 11:21 PM


Where do you live in E-Wash Bobby Holeshot? I live on the west side.

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  • machoman_#618

Posted December 25, 2004 - 04:23 AM


sorry my brother, My frig don't get that cold here,lol.(big evil laugh here)

  • MXof21

Posted December 25, 2004 - 10:07 AM


I agree, you have to give the throttle a few good twists.

  • Satch0922

Posted December 25, 2004 - 10:15 AM


I agree, you have to give the throttle a few good twists.

Boyd, I used to give the 426 a couple of twists of the throttle when it's really cold outside and it would spring to life. You might try one twist and then a couple of kicks and if it doesn't light up then another twist or two and keep kicking. Be careful not to flood it.

  • Indy_WR450

Posted December 25, 2004 - 11:35 AM


to avoid flooding it run a 72 starter jet for the colder weather. :cry:

  • JT_Thumpster

Posted December 25, 2004 - 05:24 PM


I've had my 426 for a week and riddin it twice and it starts on the 3 - 4 kick

Oh and where are you from in Oregon?

  • PumpkinHumper

Posted December 25, 2004 - 07:48 PM


to avoid flooding it run a 72 starter jet for the colder weather. :cry:

Listen to Indy. He knows his jetting. The starter jet maked a HUGE diferance in cold weather starting. Not the pilot jet but the starter jet. Its in the bottom of the carb next to the pilot and main.

In the winter on my YZ400 I go one size bigger on the main and pilot. Go from a 65 starter to a 72. Move the needle up 1 notch. This is in say 20 deg weather. Runs soooo much better.

The starter jet curses that starting-stalling, starting-stalling, starting-stalling, starting-stalling, till it stays running routine.

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