ruggle 0 Posted July 27, 2013 I recently bought a used 07 yamaha wr450f that has never quite run right. It starts easily, but used to idle poorly. It would run like a champ beyond idle, but when it was cold I would have to keep blipping the throttle to keep it running. SO, I yanked the carb, replaced the pilot jet with a new one of the same size and installed a remote adjustable air mix screw. Set that thing right, and now the bike starts and idles perfect. Problem is that now anytime I hit the throttle hard (3/4 or more) the bike totally loses power completely for a moment, then kicks back in full force. Not so awesome of a surprise. Anyways..... I'm too busy to keep pulling the carb and trouble shooting this thing right now. Anybody have a good recommendation on a shop to take it to in the North County that will get this thing running perfect the first time? Thanks Share this post Link to post Share on other sites
TrophyHunter 15 Posted July 27, 2013 I know it's N Cty but C & D knows that bike. The owner, Steve, used to race WR's and mine ran strong after dropping it off there. Might be worth the drive. Share this post Link to post Share on other sites
ruggle 0 Posted July 27, 2013 Thanks Ken. I think I'll give them a shot. Share this post Link to post Share on other sites
Corpic 5 Posted July 27, 2013 I recently bought a used 07 yamaha wr450f that has never quite run right. It starts easily, but used to idle poorly. It would run like a champ beyond idle, but when it was cold I would have to keep blipping the throttle to keep it running. SO, I yanked the carb, replaced the pilot jet with a new one of the same size and installed a remote adjustable air mix screw. Set that thing right, and now the bike starts and idles perfect. Problem is that now anytime I hit the throttle hard (3/4 or more) the bike totally loses power completely for a moment, then kicks back in full force. Not so awesome of a surprise. Anyways..... I'm too busy to keep pulling the carb and trouble shooting this thing right now. Anybody have a good recommendation on a shop to take it to in the North County that will get this thing running perfect the first time? Thanks I have had great results W/ Tokyo Mods in San Juan Capistrano you would need to take carb off the bike and bring it to them give them all the info of the bike. It will come back perfectly jetted and start idle and run perfect in my experience. I usually do all my jetting and maintenance myself but had a CRF 450 X the sat for a year and a half gas totally clogged up the carb , I took the carb apart several times and never got it to run correctly. I got my carb back from Tokyo Mods and that bike had never run and carberate so cleanly. It cost me $ 200 W/ parts but I felt it was well worth it. Share this post Link to post Share on other sites
Desertrunner 0 Posted July 27, 2013 The pilot's function at 3/4-WOT is next to nothing and wouldn't cause the bog. It sounds like you might have missed something putting the carb back together. Share this post Link to post Share on other sites
Goofy Footer 539 Posted July 28, 2013 I'd love to hear your impression of the bike - power, suspension, flickability etc Share this post Link to post Share on other sites
ruggle 0 Posted October 2, 2013 Just thought I'd follow up with a general recommendation for C&D Cycle Center. They had the WR up and running right the first time, no hassle. VERY reasonable cost too. The problem ended up being a combination of a dirty carb, missing washer, small-ish main jet, and partially completed air box snorkle removal mod from the previous owner. Very glad I passed this job off to a shop that knew what they were doing. Saved me at least one more Saturday afternoon. Share this post Link to post Share on other sites