Help!!! Need help finding a pilot jet!! ASAP

6 replies to this topic
  • dkuntz

Posted August 06, 2001 - 02:19 PM


Just came back from riding in the mountains of Colorado (Rampart Range). Had a great time, but can't get any low end power out of my bike. From the posting on this site about altitude jetting I am needing to drop to a 42 pilot jet, but I have spoken to three dealers and they give me a standard Keihn Pilot jet and my WR takes some strange jet. The pilot jet I pulled out is a 45 and looks more like a Mukuni (sp?) than a Keihn. What's up with this?

Am I loosing my mind?
Is this a rare jet?
Why am I having so much trouble getting the correct jet?

I would appreciate any help. I leave tomorrow for Colorado (Gunnison area)and desperatly need to get my jetting correct.

Doug Kuntz
Kansas (105 degree weather lately)
98 WR400
Stock Pipe and header - no baffle
Stck Air Cleaner
Top of airbox removed
WR timing

  • Hick

Posted August 06, 2001 - 03:05 PM


I’m not a doctor, but from a mental health perspective I think you check out fine.

Anyway, no, the Keihin Slant FCR doesn’t use the same pilot jets as “normal” Keihin carbs. These jets are not rare, but unfortunately intelligent dealers are.

You may also try dropping your needle a clip or two.

  • dkuntz

Posted August 06, 2001 - 03:34 PM


Thought I was loosing my mind or something. Thanks for the help and yes I have already moved my clip to the #2 position.

Kansas Settings:
Main 170
Pilot 45
Clip #4
Fuel Screw = 2 turns out

Colorado Settings tring to achieve.
Main 162
Pilot 42
Clip #2
Fule Screw = 1 3/4 turn out.

Thanks a lot!!

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  • James_Dean

Posted August 06, 2001 - 09:25 PM


Try turning in the pilot screw in more, 1-1 1/2 turns. Then have your Yamaha dealer look up the part number for the '98/'99 WR pilot jet or call Sudco and be sure to get their FCR version of pilot jet.(1-800-998-3529)

  • Hick

Posted August 07, 2001 - 08:14 PM



Glad to see you still check up on us from time to time. Thanks, and don’t be a stranger.

  • freestyle111

Posted August 09, 2001 - 06:02 PM


i had same problem.i went to 3 different dealers when i showed them pilot jet they acted like it was a part from outerspace.none of them could find it on there computer or even had any idea where i could purchase a similar pilot of them even said "it couldnt be from stock wr400 maybe someone put a jetski carb on my bike".i havent been back to that dealer since.i ended up ordering the correct jet from dennis kirk.

  • Rich_in_Orlando

Posted August 09, 2001 - 06:56 PM


You could also order the jet from Yamaha. Here are the Yamaha Part numbers for and prices from

<LI>3TJ-14948-05-00 STD JET (#45) $8.40
<LI>3TJ-14948-03-00 ...JET (#40) $12.51
<LI>3TJ-14948-04-00 ...JET (#42) $8.40
<LI>3TJ-14948-06-00 ...JET (#48) $8.40
<LI>3TJ-14948-07-00 ...JET (#50) $8.71


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