50cc eton beamer lost compression

[capt1992]

I have a 2005 eton beamer ll with about 3000 miles on it. The other day it suddenly lost power and stopped; fortunately in the driveway. The starter spun it over like crazy so I figured it had little or no compression. I pulled the plug and checked for piston travel and all seemed well so I pulled the head. I found a deep score down the cylinder wall down to what I think is an exhaust port. I'm thinking I might have a broken ring. If I don't have a broken ring, is that score (about a 32 of an inch across) enough to cause the compression loss?
I'm thinking a top end kit would probably solve this but I would appreciate some feedback from folks with more knowledge than I have. Thanks!

[Rebel]

Welcome to the forum

If you pulled the head off, I'd go ahead and pull the cylinder too. It does sound like it could be a broken ring. If the ring is broken it will loose compression. I'm not a 2 T person, we have a couple of them that are pretty good with them that come in and you might want to wait for their opinion. (jmkjr72, 90GTVert are two of them)

Seems to me that most if not all 2 T's have just two rings. If one is broken you won't have much compression.

Now would be a great time for some tuning on it. if you are into that stuff.

[shiftless]

With the milage, your rings could just be worn
If it broke a ring.. you wanna pull the whole top end and check for damage to jug, head etc

Might as well add a bbk while its down ;-} My beamer likes the added cc's

[Rebel]

I understand you can work wonders with these things, bbk, porting, tuned exhaust, one of the guys installs reed valve spacers. A 50cc 2 t can be tuned to outrun a 150cc 4 stroke.

[jmkjr72]

you should have 2 rings with only 3000 miles on a 2 stroke if you used a good quailty oil you shouldnt have any drop in compression if you are stock

there are a few options you could have a busted ring a chunked reed or lost a circlip or seized for some reason

please take and post some pics
the head the top of the piston
the damage to the bore

and heck why do a stock top end kit get a nice cast iron sport kit like the top performance trophy and your scoot will be wicked fast for a little "50"