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05 WR450 Jetting

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Hey James,

My apologies for bugging you mate as I am sure you get swamped with questions, but I do need your help or anyone else out there.

Firstly a quick history: All the free mods are done on my bike. I live in Dallas, approx 382-586 ft ASL. The temp today was 56 degrees, damp.

Anway last night I installed your kit. 170 main, and blue needle, clip #4. Great instructions by the way.

Today riding, was a nightmare. In the lower revs she kept dying. If I rolled hard on the throttle she died, which was hell througth the woods. I increased the idle and tried to adjust the fuel screw anywhere from 1 turn all the way to 1 3/4 turns but she just runs rough.

From mid-range on she pulls like a beast.

I would welcome any suggestions as the two different dealers here have not been much help.

Thanks

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hmm ok i suggest that you either take out your jet (very easy) under your carborator there is a nut take and w/e number it says on it go about 3-4 numbers higher.. i already had this problem and now my bike rums great (its only about 4$ the go to your local dealer and get a new jet very easy

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Sounds like you want to put in a 40 leak jet and adjust tha AC pump to have no play. You are most likely getting the lean bog. I also run a zero leak jet in the winter. ( I took the stocker and silver brazed it shut). Leave the needle and main alone and make sure you have a 48 pilot as well. :)

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Spend some coin and get your thumper running correctly. As I read the jetting woes of some here I wonder why everyone has tunnel vision. Having more than one way to skin a cat applies to jetting issues. I could go into a long discertation about how well my 525mxc runs but i'm not sure people can pry themselves from this site long enough to ride their bikes. Try this, call 719-475-2624 or slavensracing.com and invest the best $100 you'll spend for your thumper. I could also attempt to impress you with the quantity and different manufacturers of thumpers I've owned, but for what. You own an '05 WR 450 and need the carb to act right so what does it matter what i ride or have ridden. Buy the Slavens "No Bog" sleeve and the jetting/needle combo Jeff Slavens sells for your 450 and your problems will be solved. Incorrect jetting, while maybe better than stock, is the most irritating and annoying problem for a rider. Try to disregard all the hype with accel pump adjustments and diaphragm changes that I read and get your CARB jetting correct. Or continue to spend your time posting and reposting threads on the web and just look at your WR in the garage instead of roosting. You have choices!

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Sounds too rich on the needle to me..Try lowering it to clip three or use the red needle on 5 :) mine runs perfect in similar conditions..I did use Indy's advice and change to a 48pj and 72sj for easy cold starts. It ran perfect before that change anyway.

Question :) has anyone disabled their acv on the 05? if so, what pj and paj did you use? Thanks and sorry to step on your thread.. :p

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bushman06,

Just as DOMENIC mentioned, set the needle clip position to 3rd from top to lean the jetting a step. The damp weather is making your jetting richer with humidity. The next choice is to use the leaner red marked needle in the 5th from top clip position.

The stock pilot jet should work well after adjusting the fuel screw to near 2 turns.

Thanks,

James

BTW-The Slavens unit reduces the carburetor bore down from 39mm to 38-37mm. Not everyone wants a smaller carburetor when bogging isn't a problem on a well adjusted bike.

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Sounds too rich on the needle to me..Try lowering it to clip three or use the red needle on 5 :D mine runs perfect in similar conditions..I did use Indy's advice and change to a 48pj and 72sj for easy cold starts. It ran perfect before that change anyway.

Question :) has anyone disabled their acv on the 05? if so, what pj and paj did you use? Thanks and sorry to step on your thread.. :)

If you bypass the acv circuit you will need to lower your pilot jet two sizes. :D Be prepared for more Formula 1 style backfires! :p

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05 WR 450 I had the same problem with the blue needle.Indy has done alot of work and I thank him for it he has gottin me real close but his recommendations for my bike are a little rich.

I am running the red needle on 5, stock pilot,40 leak 170 main.

Temp 40-60, elevation 2000-3000.

I still have a very slight miss once in awhile.going to try red 4

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If you bypass the acv circuit you will need to lower your pilot jet two sizes. :D Be prepared for more Formula 1 style backfires! :)

Cooooooool :D Just thinking out loud :p Maybe I'll just do the YZ cam for now :)

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