that gurgling..sputtors..??bakfires?


20 replies to this topic
  • bigwake

Posted August 02, 2007 - 04:58 PM

#1

i went for my first ride on my 03 yz450f..couldn't have been more pleased with this thing!..anyone know what that sputter/backfire/gurgling noise is when you let off at high speeds? just curious.. thanx-josh

  • ekim08

Posted August 02, 2007 - 05:29 PM

#2

its normal u can hear it on all 4 stokes and more on harleys its just when the bike reves down

  • shortburb

Posted August 02, 2007 - 07:09 PM

#3

from what i gather that decel popping is supposed to be minimal but iv spent all weekend playing with jetting and cant get it to go away......

  • bigwake

Posted August 02, 2007 - 07:36 PM

#4

ehh i can live with it! i actually think it sounds cool..haha

  • R1DEAN

Posted August 02, 2007 - 08:14 PM

#5

i went for my first ride on my 03 yz450f..couldn't have been more pleased with this thing!..anyone know what that sputter/backfire/gurgling noise is when you let off at high speeds? just curious.. thanx-josh


I usually find it's a lean pilot jet and/or a air leak in the header pipe.

  • bigwake

Posted August 02, 2007 - 08:23 PM

#6

ok i'll check it out

  • ben_suhard

Posted August 02, 2007 - 11:01 PM

#7

anyone know what that sputter/backfire/gurgling noise is when you let off at high speeds? just curious.. thanx-josh

It's the unburnt fuel in the exhaust pipe igniting due to the heat when air rushes in(supplying oxygen) through the end of the pipe. It can be worse if the pilot circuit is lean. You might want to read this, http://www.motocross...032722A4D5D52E3 and grab an (easy)adjustable fuel screw from the TT shop, they're $20. If you get one, make sure it's for your bike(year model). I think there's only two different fuel screws sold by Zip-ty.

  • grayracer513

Posted August 03, 2007 - 07:27 AM

#8

Read:

http://www.thumperta...599#post3710599

http://www.thumperta...613#post3350613

(from Common Threads)

  • bigwake

Posted August 03, 2007 - 07:30 AM

#9

ok i'll check them out! thanx

  • Ga426owner

Posted August 03, 2007 - 10:55 AM

#10

I usually find it's a lean pilot jet and/or a air leak in the header pipe.


100% totally agree with fine tuning the fuelscrew....(buy one u will need it)...my 03 does not do this anymore.....:thumbsup:

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

Posted August 03, 2007 - 11:14 AM

#11

maybe i'll look into buying one! thanx guys

  • Ga426owner

Posted August 03, 2007 - 11:19 AM

#12

maybe i'll look into buying one! thanx guys



the best 20.00 you can spend :thumbsup:

  • bigwake

Posted August 03, 2007 - 11:46 AM

#13

but what happens if i don't buy one??..is it really a NEED or is it just so you don't hear that noise anymore...because i think the noise is kinda cool..haha

  • Ga426owner

Posted August 03, 2007 - 12:40 PM

#14

:excuseme: :excuseme: :excuseme: :excuseme:

  • R1DEAN

Posted August 03, 2007 - 12:47 PM

#15

Be careful which adjustable fuel screw you buy, I have seen one that was
just enough different than the original, it did not fit the hole it is designed
to go in to. I'm haven't check all the different ones to know which one to recommend.

  • Ga426owner

Posted August 03, 2007 - 12:51 PM

#16

I have been using ZipTy Racings versions for several years with great results....:thumbsup:

  • bigwake

Posted August 03, 2007 - 02:13 PM

#17

..so if i dont buy one..??..i cant spend anymore money on this bike..

  • flintlock28

Posted August 03, 2007 - 02:48 PM

#18

The fuel screw can make a big difference on how the bike pulls from idle to a quarter throttle or so. They're worth using simply for the fact that as the temperature, Humidity/Altitude change, you can fine tune the carb easily.

  • bigwake

Posted August 03, 2007 - 03:55 PM

#19

ok thanx everyone!

  • ben_suhard

Posted August 03, 2007 - 06:59 PM

#20

but what happens if i don't buy one??..is it really a NEED or is it just so you don't hear that noise anymore...because i think the noise is kinda cool..haha

They're not noise reducers, they're for tuning your bike!:D If you like the noise, you'll still hear it when going from fully open throttle to fully closed, even when your pilot circuit is tuned.:thumbsup:





Related Content

Forums
Photo

YZ450F 03 Sparks driving me crazy by SirAttard


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies
Forums
Photo

James Stewart back on a YZ450F by YamaLink


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies
Forums
Photo
Motocross

Thinking about Yamaha 250... by Arctic Pride


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  491 replies
Reviews

Yamaha YZ450F 2017 by Chris.GVS


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

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
 
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.