I cant belive I was this dumb am I screwed?

[mark halfmann]

So I bought my son a Yahama PW50 Dirt bike and he ran half a tank of gas through it before it started having starting problems. I kicked and kicked it with no luck of it getting started. I finally got it started by spraying some carb cleaner in the intake. After getting it started I put a lot of sea foam and ran it very hard due to the only/previous owners son only riding it 3 times and thinking it had carbon build up or some old gas. It ran great untill it was parked. The last time I went to start it wouldn't and I ended up ordering a spark plug as it didn't have the best spark.As I was looking to see the gap it needed to be set to I SAW IT WAS TWO STROKE!!!! I tested the compression and it is still surprising 120 PSI. Before I ordered the spark plug I sprayed wd40 and card cleaner in the spark plug hole and it never would fire. Did I roast the hole engine? By some miracle does it have a low oil sensor?



I feel like i have seen a goast yall.... still cant belive i did somthing this dumb. Wow.

 

[RM_guy]

The PW50 is oil injection so as long as there was oil in the oil tank you are fine. You didn't mention if there was or not. The fact you were able to run it hard for a while means there may have had oil in it. Also Seafoam has lubricant in it so that would have helped if there was actually no oil in the tank.

In any case, the damage would be with the crank and rod end bearings...and of course the piston and cylinder. I'm not sure what compression a PW50 is supposed to be at but 120 psi is low for a bigger 2 stroke. It may be fine since it's a low performance motor. (Edit: I did a quick internet search and 120 psi sounds pretty good.)

Check for oil in the tank. If there wasn't any there I'd pull the cylinder to check the cylinder bore, rings and piston for wear. Also check for any slop in the crank or rod end bearings. If you did have oil than you are good to go!

 

[mark halfmann]

The PW50 is oil injection so as long as there was oil in the oil tank you are fine. You didn't mention if there was or not. The fact you were able to run it hard for a while means there may have had oil in it. Also Seafoam has lubricant in it so that would have helped if there was actually no oil in the tank.

In any case, the damage would be with the crank and rod end bearings...and of course the piston and cylinder. I'm not sure what compression a PW50 is supposed to be at but 120 psi is low for a bigger 2 stroke. It may be fine since it's a low performance motor. (Edit: I did a quick internet search and 120 psi sounds pretty good.)

Check for oil in the tank. If there wasn't any there I'd pull the cylinder to check the cylinder bore, rings and piston for wear. Also check for any slop in the crank or rod end bearings. If you did have oil than you are good to go!

THank you! The oil tank was dry as far as I can tell. The two stroke oil will come in tommorrow and I will let you know what happens.

 

[truespode]

Double check the previous owner didn't disable the oil injection. I know in some oil injection bikes people will do that because they prefer to mix the gas instead of trying to figure out the ratio with the injector.

It is doubtful since you said the previous owner's son only rode a few times but definitely need to confirm.

Ivan