Scored cylinder

[Tsvarian123]

Cylinder 50 mm bbk scored only on exhaust side other side perfectly smooth . Its so bad rings are filed smooth any ideas ..?

[Mystic]

I think they make a 51 52 or 53mm bore maybe bore it out to one of these sizes and get the piston kit to correspond otherwise it is garbage

[Tsvarian123]

Yea but any ideas what could cause it only on exhaust side ?

[Mystic]

a few questions, what kind of filter, exhaust, and carb where you using? and what size main jet? my first guess would be you ran it lean but thats not 100 percent or you didnt properly heatcycle before you ran it at WOT

[eliteguy50]

Yea but any ideas what could cause it only on exhaust side ?

That was the hottest side. Otherwise we need pics to tell you more.

[Tsvarian123]

Can't post pics for some reason can I email to one of ya to post em ??

[Tsvarian123]

Let me edit the post the cylinder is alright a few lines but not too bad nothing a lil Brillo couldn't cure the piston is scored deep groves in it rings filed down to flush only on exhaust side .. Sorry

[eliteguy50]

Let me edit the post the cylinder is alright a few lines but not too bad nothing a lil Brillo couldn't cure the piston is scored deep groves in it rings filed down to flush only on exhaust side .. Sorry

can you catch your fingernail in any of the lines?

[Tsvarian123]

U can feel they are there like small scratches but barely .. On the piston though the grooves are very deep

[eliteguy50]

Picture links:
http://img708.imageshack.us/img708/9190/img5902z.jpg
http://img809.imageshack.us/img809/6550/img0186ym.jpg
http://img59.imageshack.us/img59/9366/img1001y.jpg
http://img404.imageshack.us/img404/351/img4580k.jpg
http://img805.imageshack.us/img805/8075/img4461z.jpg
http://img812.imageshack.us/img812/1963/img4983z.jpg

[Tsvarian123]

Pics posted thanks to elite guy now ya can see what I mean

[Bear45-70]

[bakaracer]

That's a lube issue when is seizes like that. Not enough oil flowing through. What carb and jets are you running?

[JJ Joseph]

Cylinder 50 mm bbk scored only on exhaust side other side perfectly smooth . Its so bad rings are filed smooth any ideas ..?

The only solution is to buy a new piston or piston+cylinder. This is normal 2-stroke maintenance, especially if you're running lean. But with scooters it's usually convenient to buy a new cylinder+piston as a package than just the piston. My last Ruima 50mm set (including cylinder head, bolts, gaskets, etc, was only $88 + $25 shipping). Pay attention to the quality of the finish of the cylinder. It looks like your exhaust port is rough around the edges which will chew up your rings.