American Sportworks manufactures a little UTV and brands it under different names for different companies ( including 2 of thier own models ):
American Sportworks LandMaster LM200 & Chuckwagon CW200
Menards Yardsport YS200 ( the one I own )
Tractor Supply Co. Trailwagon TW200
Home Depot Bulldog BD200
The motor is listed as a 150cc " SLI " engine. I could not find anything about the SLI engine, anywhere. The engine in my cart is labeled " Hammerhead ". Turns out these engines are a widely popular chinese copy of the Honda GY6 engine. Do a google for 150cc GY6 and you will find a huge wealth of information on these little engines, including how to heavily modify them. What I did like about this engine over some of the other knock-off's, is American Sportworks included a real spin-on automotive type oil filter. The other chineese knock-off's I seen had a simple metal screen cup to clean ( located under the drain plug ).
I was able to take one for a spin at the Menards lots, before I bought it. I weigh 295# and I had a sales guy get on ( said he weighed 245# ) and this little cart had good take off and got us going around 25mph fairly quick.