Intermittent low rpm / idle problem

1 reply to this topic
  • tshu59

Posted July 30, 2014 - 09:29 AM


07 WR450 Have an intermittent issue with my bike. Generally runs fine then it goes into backfiring on deceleration towards the low rpm range, then it won't idle, just cuts out when you pull the clutch in.. I can turn the idle screw 1 1/2 turns and it will idle fine but still back fire. Then all of a sudden things change, the idle ramps up high and the backfiring stops. I turn the idle back down the 1 1/2 turns till it idles low again and it runs fine just like it should. It does not matter if it is at running temp or stone cold. Yesterday I road 20 miles just fine then acted up in last mile. Today it acted bad for the full 30 miles. I did change the plug, disconnected the fuel mixture sensor and neither helped. I'm putting in a new battery tomorrow because the conductivity is poor but it still puts out 12.8 v under a load. It is the original battery. Any ideas? 

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

Posted July 30, 2014 - 12:19 PM


Fuel mixture sensor ??? 


No such thing on your bike.


You might mean the TPS on the carb.....



You need to service your bike!


At  the very least:


- replace the pilot jet with a new one

- clear  the pasage above it with fishing line and spray cleaner

- get an R&D remote fuel screw and learn how to adjust it

- re pack your silencer

- tighten your header, or replace the crush washer

- clean polish and lube your hot start plunger, and probalby replace the cap on top, as it cracks and or leaks


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.