2 Stroke KTM 250 MXC 1983 Jetting Issues

Earlier this month I replaced the air filter on my 1983 KTM 250 MXC. It ran great before i replaced the air filter, after installing the new, oiled air filter, the bike had trouble starting, idling, and started creating black sludge coming out of the muffler.

Any suggestions?
 
Earlier this month I replaced the air filter on my 1983 KTM 250 MXC. It ran great before i replaced the air filter, after installing the new, oiled air filter, the bike had trouble starting, idling, and started creating black sludge coming out of the muffler.

Any suggestions?


Like Srad said. Clean the carb. Chances are you over oiled the filter too. Happens all the time.
 
Earlier this month I replaced the air filter on my 1983 KTM 250 MXC. It ran great before i replaced the air filter, after installing the new, oiled air filter, the bike had trouble starting, idling, and started creating black sludge coming out of the muffler.

Any suggestions?
Awesome scoot! Man o' man, I love late 70's and 80's bikes....,black sludge eh? Crank seals come to mind, as Dan and Michael said, clean the air filter, just a light amount of oil and grease the sealin' lip. Pull your plug, clean and re-pack your muffler and pipe<just as nasty a job as cleaning your air filter. Try a different pre mix ratio, and oil. I runs Maxima 927 for many years, and the Lechiens run the bizness. I use a 40-1 ratio for my red devils.....
 
Top