Hey,
It's got a 17" rear wheel. The bikes have held up pretty good. The welds are not pretty and both the frame and motor are low-tech but for our needs the Hensims have been just fine. I did have to replace the fuel-tank (leaky fuel petcock) and the exhaust pipe (small rattle) under warranty on my bike. My wife's has worked flawlessly. As far as performance is concerned, check out this thread...
http://chinariders.net/modules.php?n...iewtopic&t=332
As an aside, for my part, I've spent quite a bit of attention and time to these bikes...I'm happy enough with them and trust them enough to start plans to throw the bikes in the back of the truck next summer and do longer 1- or even 2-day trails/tours. My buddy has beat the crap out of his and has done nothing to it except the needle-clip trick on the carb. His runs and works fine still.
The only thing I would say you have to watch for is I think there is a problem with consistency sometimes with all China manufacturers. In other words, spend some time when you first get the bike and make sure you didn't get a "Friday bike"...I say that because, though slight, there is a difference in quality of assembly between the two bikes I even got.
Hope that helps,
R.