Getting Cold.....

I've owned my yz426 for 2 weeks now and when i bought it ran perfectly. Now that the temp has drop down to around 40-50, the bike will kick over and start, only to idle for a second or two. I was thinking about adjusting the air screw, but wanted some advice first. I am new to the 4 stroke world. Thanks in advance!

I just got one also .I want to no to :)

someones gotta know this.....

I just rode the other day and it was 19drgs! Bike ran fine 'cept the susp took 6hrs to warm up.......LOL! and the pilot was a little stiff and cold!!!! Hadn't started for 2wks and just blipped the throttle w.o. 2 times and fired up on the 1st kick! Gotta love yammy!

Maybe you are a little lean? for winter temps and humidity?

40-50 cold?

We drive down south 5hrs for temps like that! and have to suffer w/30's for 3months!

YZ dude change your spark plug and your oil.

I use Yamalube 10W50 semi synthetic. ------- 2001 YZ 426 F ---1996 XR 650 L :)

I have noticed the same thing on my bike. I adjusted the pilot jet out a full turn and the bike starts and stays started instead of doing the ol' sputter and die. Since air gets denser with a cooler temp it is only logical that the bike would like a little more fuel since there is more oxygen coming in with the cooler air. Give it a twist and see what it does for ya, it helped mine.


On the thumpers it's a fuel screw not an air screw. Out is more fuel (richer) which is what you need when the temp drops. Try 1/4 turn at a time till it you get fastest idle.

Had to back my fuel screw out 1/2 turn more myself. Make one of the cool adjustment tools Garrett shows on his site. It'll cost you about $3 and you can adjust w/o having to pull the carb out and you can EASILY see how much you really turned the screw!

Oh yeah, mine likes 1 good pump of the throttle when it's ice cold. After that, 1st kick everytime.

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