strange new problem

lately I have been fouling a lot of plugs.. I mean one a ride or more... This is what I have noticed Put in a new plug go riding bike runs fine live it set till it cools down 30 maybe 45 min. When I start the bike bingo fouled plug.. while the bike is setting I leave the gas pitcock turned on.. other than that I don't touch it... I cleaned the carb still no good... I need help my old 2 strock was easier on plugs..

try a different manufacturer. go to a softer plug ie 8 down to a 7 while you find out the real problem.


Possible float problem, turn your gas off when you park it. Use the hot start when you restart it. See if the problem stops.

Post your jetting - pilot, pilot screw, needle, clip position. YZ/WR cam timing? Exhaust? Model and Year?

Minor adjustments like turning IN the pilot screw or moving the needle a clip position leaner may be needed.

There are lots of jetting tips on this site if you search back.

pilot 45 main 165 dtm 3 slot wr timing screw 1.25 turns out

This is stock jetting for '98/'99WR's. Unless you are at high altitude or hot temperatures, it should be ok. If you are doing alot of low speed running, the DTM#3 could be switched to DVP#4 to lean out from 0-1/4 throttle. Other things like float height or an over-oiled air filter? Make sure the pilot air jet is not clogged and the choke is closing properly if you take the carb off again.

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