yzf 400 carb hesitation


5 replies to this topic
  • frig

Posted April 24, 2006 - 05:49 AM

#1

I own a 1999 yzf 400 low hours looking for some info about low end carb hesitation or a dead spot int the
beginning of throttle, bike runs strong mid to high in talking to other riders sounds
like it always been a problem. I installed a hot shot from boysen and didn't notice a big difference. wondering about jetting pilot circuit? Is that were the
problems lye??

  • One Louder

Posted April 24, 2006 - 07:57 AM

#2

0 to 1/4 throttle is affected by the fuel screw and the pilot jet. Have you cleaned the carb good? do you have an extended fuel screw? these are very touchy and the fuel screw will need frequent adjustments

BTW welcome to TT :thumbsup:

  • eddiev

Posted April 24, 2006 - 10:57 AM

#3

I have a 99 also and I think spending time with the jetting helps a lot and I bolted on a part called a P38 from Factory R&D. It helped even more!!!

Good Luck!!

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

Posted April 25, 2006 - 10:55 PM

#4

Clean yor accelerator pump on your carb its simple, and its your soulotion to yor problem

  • frig

Posted April 28, 2006 - 09:48 AM

#5

Yes, cleaned carb, what is a P38 and where do yoou purchase

  • ben_suhard

Posted April 28, 2006 - 10:26 AM

#6

I own a 1999 yzf 400 low hours looking for some info about low end carb hesitation or a dead spot int the
beginning of throttle

Even when the bike is jetted properly, you'll still get a bit of hesitation when opening the throttle quickly because with four-strokes, the engine doesn't produce as much vacuum as a two-stroke at low revs. One trick is to turn the idle up a bit so that the engine is creating more vacuum.





Related Content

Forums
Photo

yz250x vs 450 4t comparisons (preferably desert riding) needed by JakeNorthrupYZ450F


Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 9 replies
Forums
Photo

Snake pit oct 30th by The Anvil


Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 replies
Forums
Photo

2016 YZ450 by CaptainKnobby


Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies
Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews
Forums
Photo

First Hare scramble tips by dhend8


Dirt Bike   General Dirt Bike Forums   General Dirt Bike Discussion
  • Hot  33 replies
 
x

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.