04 Yz450F stalling when giving throttle after a coast..

5 replies to this topic
  • Toobold30

Posted May 30, 2004 - 05:14 AM


Any ideas why my 04 yz450f would be stalling at a blip of the throttle from a slow speed....no popping or nothing on accel or anything....just if i pull in the cluth after coast down a slow trail and hit the throttle it will die...i was wonder if anyone else had this problem...but overall this bike is awesome...thank everyone :thumbsup:

  • crayztwentyseven

Posted May 30, 2004 - 07:50 PM


Hey I have this problem too sometimes. I'll just be coasting and go to do a burn out or somethin and it will just die. My dad is really good with bikes and engines and says that it is too rich, or that the accelerator pump is adjusted wrong. Mine does not do it very often and when it does its only after the engine has dropped down to the slow idle. So I am not too worried about it, but if it ever quits in a higher rpm then I'll definately have to fix it, because thats the last thing you want to happen on the face of a triple :awww: :thumbsup: :lol:

  • OC768

Posted May 30, 2004 - 07:51 PM


there is a laundry list of situtations that could be occuring, but what comes to mind first for me is..

- make sure the bike is warmed up thoroughly before trying this trick.

- check idle setting, too low/high can stall it if you feed a handful of throttle then chop it quick.

- fuel screw - adjusted properly?

..thats all I can think of, hopefully you'll get some more info.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • squad56

Posted May 30, 2004 - 09:05 PM


all of what oc said was correct. make sure that those are all adjusted first. i have also had this problem. yet what you need is a flywheel weight. for some reason the flywheel isnt heavy enough and when it gets down to low coast or low idle it kills the bike. i havent bought one yet but i am gonna get one soon. go down to your local yamaha dealer and ask them what size weight you will need. it will be something like 6oz,8oz,etc.hope that solves your problem.

  • 426_Texan

Posted May 30, 2004 - 09:08 PM


-Carb/Air filter need a good cleaning?

-Spark plug in good shape/gapped correctly?

I always start with these when trying to find a problem before starting to change adjustments/jets.

  • Vet28

Posted May 31, 2004 - 03:42 AM


i have the same problem. i ordered the zip ty fuel screw and once i have it. i'll get busy.

first, make sure the fuel screw is as close to perfect as possible. i have heard going to a smaller pilot (like 40) helps. if not, try a size larger. lastly you can back off the timing cam on the accel pump. take the cover off the side of the carb and back the screw off slightly (liker 1/4 turn). this adjustment makes a big diff. you will notice less initial hit out of 1/4 turn. however, if the pilot sizing is the problem backing off the accel. pump isn't the best solution.

good luck,

vet28 :thumbsup:

Related Content


Wilson the Blue Privateer by jetfuel

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  50 replies

Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride

Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies

05 yz450f not fast enough by RedeyeYZ

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  38 replies

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.