Carb problems , Need Help ASAP

10 replies to this topic
  • Ernie_Taylor

Posted July 21, 2005 - 03:06 PM


I have a big ride this weekend and levee friaday afternoon.

I just but a dynojet ket in my WR450 , 2003. along with a zyi tie fuel/air screew and the bike runes like crap. IThas a big miss in , like it's not getting gas or something. I tryed a new spark plug on top of the allready new plug and still the same, also I cleaned my carb, thinking this could help but with no luck.

No back fire's just large miss's or chops. :applause:

Thanks For Your help


  • WR_Dave

Posted July 21, 2005 - 03:09 PM


Did you lose the O-ring when you installed the Zip-Ty fuel screw? :applause:

  • Ernie_Taylor

Posted July 21, 2005 - 04:50 PM


Good thinking ,but I made sure it wasn't that. O ring and washer in place

I'm going to jet down to see if that works

  • new2blu

Posted July 21, 2005 - 04:52 PM


What jets did you change? What were the original jet size numbers and what are the new jet size numbers? Was the bike running bad befor the jet change?

  • Ernie_Taylor

Posted July 21, 2005 - 05:47 PM


Just jetted down and it's still the same.

Going to try butting the stock neddle back in. This is only big change that came with the kit.

Bike was OK before

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  • Texas4play

Posted July 21, 2005 - 07:36 PM


Is your carb slide in backwards?

  • Ernie_Taylor

Posted July 22, 2005 - 02:57 AM


Good Thinking again, the slide is is right.

THe jet that I was running was a 158, but the new kit calles for a 138, I 'm going to try a 158 just to see.


  • mtrablue

Posted July 22, 2005 - 05:05 AM


if you are talking about the main jet, you should have a 165 at the least. maybe a 160 if all the original baffles and plugs are in it. 168 if you've got it in race mode. 48 pilot.

  • Indy_WR450

Posted July 22, 2005 - 07:59 AM


A 138 main will burn up your engine if it runs at all! :applause:
Buy the JD jetting kit and a 48 pilot! :eek:

  • StreetbikePimp

Posted July 22, 2005 - 08:29 AM


Needle is fine. That 138 mj is your problem.

  • RichBaker

Posted July 22, 2005 - 02:15 PM


Dyno Jet uses their own jet numbering system, they do NOT correspond to factory Keihin jet numbers....


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