Quadrunner 250 4x4 2000. Seams to eat up spark plugs. Runs good for awhile then start having trouble with idle then it starts to run ruffer and ruffer till you can't get it started. Put in a new plug and it's just like new. This just takes 5 to 10 miles on the runner. I do a lot of slow speed stuff but still this shouldn't do this. Any ideas ?

 

Should have told us the plug color but... It sounds like its running too rich. Check and make sure your air filter is clean. If it is then i'd say you need to rejet the carb 1 size down should do it.

 

Could also be the needle & seat, seems to be a common problem on these 250's, I've changed a few of them.

 

SXR6 Dealer is now telling me same thing about needle valve. You said you've done it a couple of times youself. How much of a job is it ? and would you have a blown up picture of the carb,you know with part numbers and such or where can I get one,dealer seems to like to keep this a secret. Thanks

 

I don't have any pics, but it's a relatively easy job. Pull off gas line to carb, undo clamp from air cleaner side. I found it easiest to take a large phillips & reach down from top to undo carb manifold AT the cylinder, then remove it from carb. Now you can lift carb up out of frame without undoing the throttle & enrichener cables. Just flip the carb over pull off float bowl, float lever pin, replace valve & reasemble. Easy Also make sure float level is set on the low side, they run a lot better on uneven terrian this way.

 

Got it back from dealer and here it is ! Get this ! a mud wasp had or was trying to build a nest in a vent line from the carb. They said they to just about had to tear it completly apart because of line runing along frame under fuel tank to where it comes out by the others. Now runs like new. I do not park it out side so go figure !

 

That would also cause rich conditions; go figure!!!