I fouled my plug, its cold and damp. when i pulled the cap off, i didnt notice all the dirt that seeped in there. i pulled the plug out and i know dirt got in. When the plug was out i cranked it a few times by hand and dust and dirt came out. should i put a new plug in and try to wash it out, or will i damage my sleeve, piston valves etc. Please help, I can ride just not a veteran mechanic


Dirt in the cylinder is never good. Would it keep running if you put a new plug in and just started riding again? Probably. Would you notice any damage caused? Possibly not, at least not right away unless it started burning oil from a damaged valve stem seal or some pretty bad scratches in the cylinder. You could also try to flush out the cylinder some how, but you could never be sure how much dirt went in or how much you got out. It's possible, maybe even likely that there would be no significant damage if you were to flush it and then start riding again.

However if it were my personal bike, as painful as it may be, I would remove the head and cylinder and clean it all out good. Be sure to get the piston rings too, you don't want any dirt stuck in there.

One side note. If you decide to try to flush it out some how, do NOT use a shop vac to suck air through the spark plug hole or exhaust! Any air that goes through the carb on the way in to the motor will pick up gas and gas vapor in a shop vac isn't a good thing. :)

You may be able to blow some of the dirt out by blowing compressed air into the spark plug hole while holding the decompression lever open. I would recommend making sure you are at top-dead-center before trying this.

Watch out for busses. They leave nasty bruises! :)

One way to avoid this problem in the future is to blast compressed air through the weep hole on the side of the head after removing the plug cap. Keep your face away from above the engine when doing this as dirt comes out at velocity.


just throw in a plug and ride it!

(you could get hit by a bus tomorrow)


should i be concerned with dirt entering the engine through the weep hole?

Dirt and debris doesn't enter the engine through the weep hole, it gets in if the spark plug is removed without first blowing it out with compressed air.

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