Fuel Mixture Screw

[maracas]

Quick question to the experts

im buying a Fuel Mixture Screw for my WR450 06

everybody here mention the Zipty, but i have more access to buy a SCOTTS one down here in Mexico, is there some perform diference between them or are the same?

thanks!!

[trailordune]

Just as good!

[MountainMax]

they all do the same thing, they let you adjust the mixture screw externally, nice for tuning..........

[642MX]

There is no performance gain from the extended fuel screws. They only allow you to fine tune the pilot circuit of the carb. With that said, any brand will work, just as long as you can easily turn the knob.

[mtrablue]

go with the scotts. the scotts is made from brass so it will not get a groove on the tip as easy as the aluminum zipty.

[Wasabi]

go with the scotts. the scotts is made from brass so it will not get a groove on the tip as easy as the aluminum zipty.

Never had that problem?

[Fullbore4]

I am wondering if vibrations would cause a heavier (brass) screw to wobble loose before the zip-ty (aluminum) one.

How many have lost (or had it back out) their zip-ty one because thats what I have had for a short while.

[642MX]

I am wondering if vibrations would cause a heavier (brass) screw to wobble loose before the zip-ty (aluminum) one.

How many have lost (or had it back out) their zip-ty one because thats what I have had for a short while.

People loose the screws because of 2 reasons. (1).The spring is wore out from repeatedly being crushed while setting the screw and the lack of spring tension on the screw causes it to loosen and fall out. (2). People turn the fuel screw out beyond 3 turns in order to get the best throttle response and the screw falls out because the spring isn't long enough to hold pressure against the screw.

[Wasabi]

The scotts one is the T handle one right?

I got a zipty one and a T handle one on the 250F, the round headed one is definately easier to adjust. I can adjust it while rolling along on the fly when tuning. I can't with the T handle one one. But you rarely have to set it though. Something to think about.

[Thermos O Flask]

YEA,Make sure that you stretch out the spring a bit,my mates one just fell out to day and we only fitted it last night!

[MountainMax]

Oh yeah, some now sell the screws with a stiffer spring to help prevent them from falling out ( I lost one ). I now have a new one, and a spare, with spare spring and related parts, just in case.......

[thumbthrottler]

All,

my manual for an '05 WR450 does not show a fuel mix screw; and the pilot air jet does not appear to have the springs you refer to. What screw is actually being replaced?

[642MX]

All,

my manual for an '05 WR450 does not show a fuel mix screw; and the pilot air jet does not appear to have the springs you refer to. What screw is actually being replaced?

The screw is located under the carb and infront of the float bowl. If you loosen your carb and tilt it sideways you can see it.

[05WR450F]

Just a question...Sorry, im not trying to jack your thread. When you have the fuel mixture screw in, and everyone is saying "2" turns out, or whatever you want it set at, do you screw it all the way in, and then "back it out" 2 turns?

[MountainMax]

exactly right newbie, but don't force it tight, just barely tight, or you can do damage, I know my 06 had a plug in the float bowl covering my stock jet, had to pop it out to allow use ow the new adjustable screw.

[642MX]

Just a question...Sorry, im not trying to jack your thread. When you have the fuel mixture screw in, and everyone is saying "2" turns out, or whatever you want it set at, do you screw it all the way in, and then "back it out" 2 turns?

Correct. Turn the screw in until it seats (be gentle) and then turn it out until you get a crisp throttle response.

[MountainMax]

this will also help to eliminate any backfiring on decel, as you turn it out.

[thumbthrottler]

thanks guys.