170cc recommendations?
 

Old cart burning a bit of oil (she's got good power but a but smoky) so I figure new rings may be in order. If I'm going that far, why not go a bit further? Have no experience with what's good or now. I see eBay kits going for around $50 I assume may be junk like...

http://m.ebay.com/itm/Glixal-ATMT1-0...%257Ciid%253A1

I figure it's be foolish to go to the expense of getting rings when the piston/chamber may be a little meh, and more power is always better. Any recommendations? Cost is kind of high priority. I'm not broke but I only spent like 3 or 4 hundred on my 6150 a few years back. Not looking to turn it into a madman. Just figured I'd give it a little more guts if I'm already there. I have a compression checker though it's not been checked. It starts pretty strong and runs great. Just a little smoky.

... and, actually, in reading, it's looking like 155cc is as big as I can go w/o machining. Not sure if that juice is worth the squeeze. I guess one of my problems is I have a hard time reading through posts to see what will and won't work because it's, at times, inconsistent. Any way to definitely know what will work based on the motor I have? I'll go out and see if I can find any identifying marks on it to know what exactly it is and, therefore, what bolt spacing it is.

The 58.5mm is the largest that will drop in. The big bore kit will not give you any more power unless the head and cam are changed. Your stock cylinder will only fill to 50% charge due to restrictions in the head and valve train. Your power gains will be in the head and cam, once this is done a big bore will enhance the power since you now are bringing in more air and fuel. Being your on a budget I would just go with a new piston/ring kit. Stay away from cheap and go quality, the benefits will outweigh the cost. Then instead of investing in a cylinder you don't need invest in a quality cam for this will increase power output noticeably. Any questions, feel free to give me a call 662-301-1563. I'll give you the best bang for the buck.