2007 WR450F - Won't Run After Modifications

22 replies to this topic
  • CanadianWR450

Posted August 04, 2009 - 10:23 AM


a 175 main is way to big.
Start with trying out a 165 main.
Yes to rich = down on power......
How many turns out is the fuel screw now after the pilot jet change?

backfire....when you decelerate?

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

Posted August 04, 2009 - 10:29 AM


Depending on the elevations that you are riding in Utah, you are still too rich. If you are in the 4000 - 9000 ft range, I recommend a 42 pilot a 165 main, a YZ needle on the 3rd clip from the top and flip the ACV diaphrm over so the pin is pointed at the cover instead of the carb, this will help with some of the backfiring, your fuel screw should be around 1 1/2 turns out. Is your AIS system still on the bike? WR Dave

  • desertlover

Posted August 04, 2009 - 02:11 PM


07 450WR

45 pilot
165 main (bought both from yammie dealer)
yammie ais removal needle, clip 4th position (maybe a little rich)
tusk fuel screw 1 1/2 turns (rocky mtn atv)
unplug tps from under gas tank and wrap with electrical tape

After horrible stutter, with too much pain and suffering! This setup gave me a huge smile, while riding am fork canyon with my ktm buddies. :thumbsup:

My orange envy has died down, for now...


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.