Fuel mixture screw question


7 replies to this topic
  • CaptainKnobby

Posted June 19, 2007 - 05:33 PM

#1

When the tempature gets in the 80's and 90's outside when riding do you need to turn the fuel screw in to richen it in these type of temps or do you need to turn it out to lean the mixture at these temps.:thumbsup:

  • tnl

Posted June 19, 2007 - 06:03 PM

#2

I thought that turning the screw in closes up the fuel passage thus making it run leaner (less gas)?

  • mn519

Posted June 19, 2007 - 06:08 PM

#3

turn it in to lean it. turn it out to richen it.

turn it in with higher temps as there is less 'air in the air' (it is less dense)

  • grayracer513

Posted June 19, 2007 - 10:19 PM

#4

turn it in to lean it. turn it out to richen it.

turn it in with higher temps as there is less 'air in the air' (it is less dense)

Yep. It's a fuel metering screw, not an air metering screw. And increases in temp has the same effect as increases in altitude.

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  • CaptainKnobby

Posted June 20, 2007 - 04:30 PM

#5

Makes sense!.....I will do that on riding the next 90 degree day

  • Polar_Bus

Posted June 21, 2007 - 11:24 AM

#6

Blingy fuel screw is a waste of time and money. Just fatten up the pilot jet a tad, set the screw to 1.75 turns out, and just ride the dam bike. After my rejet, I have ridden in temps of 50F all the way up to 80, and my bike runs great with no screw tweaking.

  • Ga426owner

Posted June 21, 2007 - 01:11 PM

#7

Blingy fuel screw is a waste of time and money. Just fatten up the pilot jet a tad, set the screw to 1.75 turns out, and just ride the dam bike. After my rejet, I have ridden in temps of 50F all the way up to 80, and my bike runs great with no screw tweaking.


first I have heard of this....I guarantee you this does not work in my geo.......to much humidity and temp changes....

  • CaptainKnobby

Posted June 21, 2007 - 06:14 PM

#8

Blingy fuel screw is a waste of time and money. Just fatten up the pilot jet a tad, set the screw to 1.75 turns out, and just ride the dam bike. After my rejet, I have ridden in temps of 50F all the way up to 80, and my bike runs great with no screw tweaking.

I beefed up the pilot to a 48 but I have been riding my 06 with 2 1/8 turns out on the screw so when I go to the track saturday I will experiment at 1 1/2 turns out cause its suppose to be in the upper 80's this weekend here.:thumbsup:





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