backfire and splutter

ok guys,bought a 2004 wr450 3 weeks ago its been running fine. riding today and the bike has been splutering and backfireing , and when changing gear the revs stay on , came home , switched off bike and had a look for any ideas on this forum, went back to start bike and the button you press before the starter button was not lighting up and sticking ,i sprayed it with wd40 and now it seems fine lights up and i can start the bike, started it and it seams to be ideling fast then after about 3 mins settles to normal , was going to take it for a spin but then it started to pee it down (english weather) could the problem have been the button engageing and disengageing while riding, the last owner said it had been rejetted jd jets and has a fmf pipe on , any ideas cheers people

The fast idle sounds like it may be a sticky hot start. Remove the 14 mm plastic cap where the cable enters the carb and pull out the plunger. These plungers tend to gum up so clean and lube with some thin oil and re-install. Be very careful threading the plastic cap bolt so you don't cross thread it and don't over tighten. This is just a possible but common problem and good maintenance. Your ignition button is probably unrelated to the rough running and fast idle but souds like an issue also. If the sputtering continues I'd say it's time for a thorough carb cleaning. Good luck.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now