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CowboyBob

WARNING-The Fuel Screw falls out!

27 posts in this topic

Keep an eye on your Fuel Screw. 2 different WR 450's this Weekend started running poorly, hard to start, would not idle,popping out the exhaust e.t.c. In BOTH cases, the culprit was the Fuel Screw-IT WAS GONE-FELL OUT-AWOL.Not just the screw, but the o-ring,spring and washer as well. This seemed rather odd for it to happen to two different riders camped 50 feet apart.Luckily,since this was an AMA National Hare and Hound, Ty Davis was at the race in his Montclair Yamaha Transporter-Semi. He had the parts to replace everything on both bikes- Thanks Ty!-If you are concerned about this happening to you-and you should be-slap a piece of duct tape over the fuel screw hole so if it does back out you won't lose it. Option 2 is an adjustable fuel screw since it's easier to check the setting and change it without a screwdriver. The other plus is that the screw is so long, it cant fall out, it would hit the Starter first.You can guess where I got my adjustable fuel screw.....Ty Davis of course. Oh! and the good part is that my Bike ran killer all weekend-best guess from the finish line board is that I was 6th in class.This is the 2nd race on my WR and I have to say that NOTHING I have ever ridden is as good in the rocks-and there were plenty of them. :)

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Mine just fell out too 4 weeks ago. Had a Kouba on it too....

Still wondering if the additional weight had to do with it, or if it's a weak spring on the screw...

At any rate, all I know is a PS is $34 bucks :D...

Dodger :)

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Very good question. Both bikes that were affected were "as set" from the factory, neither had been adjusted at all. If we were to assume that both bikes were fixed per the TSB on the Woodruff Key before delivery (and neither was) then the screw would have been 3 turns out if (another assumption)the tech at the dealer that did the work actually set them correctly.

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2 1/4 turns out. Very close to needing to go to a richer pilot jet, but still not far enough out to warrent it falling out.

Seems to me the spring tension should be a bit greater :D.

Dodger :):D

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i thought i would revive this old post since it happened to a friend and me this weekend whilst motarding in the mountains

many flames and pops pour from the exhaust on decel (biggest tell tale sign)

i think its a pretty serious problem since it leaks fuel while out hitting the starter

we were both using zipty racing fuel screws so luckily we did not lose the whole thing

i was at 2 turns out with 45 pilot (48 too rich in mountains)

both 06 wr450s if that means anything

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We have had the screws fall out before, Both stock and Zipty's

I bought one similar to Ziptys but it has an Oring on the shaft to keep it from vibrating and havent had a problem since.

The name is Storm fuel screw at www.stormcycles.com

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I am going to drill a hole in my Zip Ty so I can put a piece of safety wire on it. I don't like the idea of loosing it.

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I am going to drill a hole in my Zip Ty so I can put a piece of safety wire on it. I don't like the idea of loosing it.

dont worry you wont lose it

it drops down hitting your starting motor.

i dont know about other years but 06 stock has a little....cap thingy for the old screw so i guess this problem wouldnt be for them other than losing tune....grrr annoying

bigdrtrdr, thanx for the link however they want 30 USD to australia.....screw that.....hehe

anyone having a mod or something to prevent this would be great

i was thinking something along the lines of plumbers tape(u know that white stuff) on the screw thread but fear fuel/engine eating it (tape that is)

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I had this happen to me last year. Was riding and all of the sudden it ran VERY lean. I could not figure it out. Then went to adjust my Zip-Ty screw and it wasn't there. LUCKILY, I knew where it started running odd and a buddy was able to find the screw, but none of the other little tidbits. Duck tape saved the ride, but I think that it is most prone when more than 2 1/2 turns out. My new spring, o-ring assembly I got from sudco is much more snug than the stock was that ran away. I do check it regularly now though.

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Keep an eye on your Fuel Screw. 2 different WR 450's this Weekend started running poorly, hard to start, would not idle,popping out the exhaust e.t.c.

Where is this fuel screw located?

Buggered if I can find it. Got a brand new 06 wr450 on Thursday and took it out for my first proper ride today. It's simply running poorly, won't idle unless choke is on (even when hot) and alot of popping.

Please help this newbie. I have scoured the manual with no luck.

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ok I've worked out where it should be. I'll have a look in the morning and have a fiddle.

It looks like the dealer did a couple of mods himself so I'll go through everything and check what has been done.

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Where is this fuel screw located?

Buggered if I can find it. Got a brand new 06 wr450 on Thursday and took it out for my first proper ride today. It's simply running poorly, won't idle unless choke is on (even when hot) and alot of popping.

Please help this newbie. I have scoured the manual with no luck.

The stock screw is hidden by a plate to make it non adjustable. You need to do the mods as described in the sticky at the top of the page. It would be better to do them before you ride the bike much more because a rich condition is better for break in than a lean one. Believe me after you do the mods the WR is a monster. Also the popping is caused by the AIS which should be removed and not the jetting.

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Yup It's true, it happened to me too about a year ago. No matter what the thing wouldn't idle. As soon as you chopped the throttle the engine would stall, no matter how high the rev's where. Damn thing was pricey too. Luckily I found the extra Kouba T -handle I bought wayyy back in 02. Thanks for reminding me, I really should check it again.

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Do australian Bikes have the AIS?

I think the Dealer has done throttle limiter, grey wire, airbox, exhaust and jet needle mods.

I would find out exactly what he changed and adjust accordingly. The Zip-Ty fuel screw is nice and while you're at it I would change the starter jet and leak jet and maybe the main jet if your dealer didn't already. You can't miss the AIS if your bike has it, which I don't think it should. It is a pump on the right side of your carb that pretty much blocks access to it. One of the things AIS does that annoys people is cause a popping when you let of the gas.

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OK....here goes

The fuel screw is definately missing. I can see the thread etc and right into the guts of the carb. I will get a adjustable screw once the shops open again tommorow.

THe aussie bikes do not have an AIS from the factory. And they (well mine) come with the the whole complianced blinkers, key ignition, headlight control and all that.

The Dealer had just done the throttle stop screw and grey wire mods =/

It is hovering around 20 - 30 degrees celcius (80 - 90 degrees) and being relatively low altitude here from the jetting guide I should be looking for a 165 main (standard) 48 pilot (came as a spare with the bike) 1.25 turns (when I get a fuel screw) 68 starter (65 standard I will leave for now) and a #50 leak jet + a JD red pin on 5th position.

With my bike I got a "DUS" needle (4th clip psn from top) whater that means but I'll install it for now along with the 48 pilot and see how we go.

-update-

ok.. the`dealer had also done the needle. The DUS needle (adjustable) was installed. I set this at 5th position... is it comparable to the jd needle in that way?

Got everything finished and back together and it runs!!

It's still like crap but i think having a fuel screw will probably help =)

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ok.. talked to a bike shop today.

Does the Zip-ty screw come with everything needed or do I need to organize a spring and washer or something also?

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ok.. talked to a bike shop today.

Does the Zip-ty screw come with everything needed or do I need to organize a spring and washer or something also?

If you have lost the old screw, you need a little spring, washer and o-ring.

And also we don't have AIS on our bikes, only US models have that crap. :thumbsup:

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