Re: Help - Help Me Get Motorized
the 2 stroke kits usually come with a 44 tooth rear sprocket, but you can buy a 50 or 56 tooth with the same hole pattern if needed... These all use the 9 hole sprockets and Dzx should have a few larger ones on his site like the 50, the 56, and maybe even a 60 tooth, but the 50 tooth is a pretty big difference in gearing and may net you around 20 to 25mph top speed with really good acceleration and hill climb, the 56 tooth will probably top out under 20mph on a 26 inch wheel, but should top out about the same as a 50 on a 29" wheel, The 56 is more for areas where there are steeper hills etc and when speed isn't important, probably worth about 15 ot 17 mph on a stock china girl in a 26 inch bike. Adding a sprocket on the rear wheel with a few more teeth has a pretty big effect on both top speed and acceleration, you'll feel it accelerate much better, but the top speed will be noticeably less as well.
I'd shoot for a 50 tooth rear sprocket with the 49 or 66cc China Girl kit to keep you under 25 mph on a 26" bike, use the 56 tooth only if you're installing on a 29er.