fouling plug

Hi all, Is about 200 miles (3 tanks of gas) normal use for a plug? Thats about all I can get out of the ngk's I put into my PA50II. I run 32:1 for a fuel mix. Would a Bosh do me better or is there some basic 2stroke trick I've yet to learn? If I used a hotter plug? (I use a bpr6hs (NGK), gapped at .28). I usually carrie a spare plug, (you do get tied of pushing the darn thing).

Mabey using synthetic oil for the mix? It's a PAIN!



Re: fouling plug

Reeperette /

Nah...stick with NGK's for a Japanese model...trying to cross over Euro plugs to a Jap moped or vice versa is a real headache and never seems to work.

The heat ranges are just...well...different.

Plug fouling is usually the sign of an overrich mixture, which prolly is cutting into your performance as well - check that first, and if that doesn't can try going up a heat range on the plug, but that's really risky if you don't know exactly what you are doing.

See if you can lean your mixture some, and do a couple of "plug chops" (running flat out for a while and then hitting the kill switch without throttling down) - pull the plug and look at it....should have a nice, tan/coffee kind of color....if it's whitish, yer too lean, if it's real dark, yer too rich.

If you can get the mix just right, not only will you not be fouling plugs, you should find a small increase in performance as well.

Good luck.


Re: fouling plug

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Re: fouling plug

Hi,Rob! Along with what the others said,I've got a feeling you may have an air restriction or too rich mixture.(That's if they're fouling)You didn't say what was wrong with the plugs(how they failed). If they're blistering the porcelain electrode sleeve or melting at the tip,you might have a too-lean mixture or air intake leak.Man,that is really hard on a spark plug and can burn your piston! If your spark is weak to the plug you'll get fouling also.BYE!

Re: fouling plug

Thanks for the replies... the plug looks black/really dark grey when I take it out. It dosen't look too bad, but of course the ped won't run. Change the plug, and wamm, it runs.

The air flow seems ok, I even took out the airfilter to try to lean it out a bit. I've got the carb adjusted as lean as I can and still have it idle. I'll try adjusting the float so the fuel level is a little lower. Other than changing the main jet is there any other ideas to lean it out a little? Also, the ped is 20 yrs old, but has only 1200mi, would the main jet be worn with these low miles? Or is this why pa50's were never big sellers?

Thanks again


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