125-200cc Piston pics.

What do the pictures say about the condition of my piston? Should I change pistonring, replace the piston or just ride? The piston have probably about 15-20hrs, mostly motocross (hard track). It runs well and is easy to start. It is a 144cc.

I med en ny kolv, den har börjat släppa förbi comp, därav det brända under ringen, vad kör du för olja och blandning.
Tycker du ska köra på 4% köp Aspen helsyntet helt sjukt bra olja, är ganska bilig desutom 98kr.

Mvh Crille

Looks well oiled in pretty good shape. Not new for sure, but okay.

You are getting a little blow by the ring so I would at least replace the ring if not the piston too.

+1 to what R_Little said.

Walt

I think a ring change wouldn't go a miss. with the blow by showing

The blow by was there when I bought the bike, 10-15hrs ago. I don´t think it has been worse.

First thing I would do is a compression test. Then if you feel it needs rings then you can at least check out the piston more closely when you have the cylinder off.

Why the pipe o-ring too?

STOP!

Never tear-down a dirty engine.
CAREFULY plug that hole and clean that thing off some. Same with the pipe. Make sure NOTHING falls into either hole. Or a piston will be the least of your worries.

Then- put the pipe back on and clean that motor.
Then- do a compression check.
Then- if nec., tear it down and inspect piston, ring and bore. If the piston/bore is beyond service limits it does no good to re-ring.

And yes- a new pipe o-ring is in order.

Happy wrenching!

I was think the exact same thing. Never, ever....ever tear into a dirty bike.

Me too.

hi, i know this is an old post now, but i was curious, how are you able to identify that the engine is blowing just from those images?

Iv just got myself a husky 125 sm and its covered 100,000 km on the clock but i dont know how many the actual piston has done, after a bit of research aparently a 2t psiton should be replaced near the 70k mark, is that correct?

I think im sufferning a bit of piston slap but i want to get a bit more knowledge on this before i clean strip and change the piston and rings.
sorry for being that annoying newb, guys.

Holy moly.....do you mean 100,000 m or 100,000km?...if so it is no surprise you have piston slap!

I replace the piston on my off-road bike every 1,000 km or so.

Okay, it is racing mileage but 100,000km is 60k miles or two trips around the earth and then some!

I was sitting here thinking the same thing. That's getting kinda 'long in the tooth' for a small block Chevy,....let alone a 125cc two stroke.

yeah, would appear i made a little mistake huh...i meant 10,000km lol

Still 10,000k is a lot of use for a piston.