What engine to use
Hi,
I just finished my first build about a month ago. I used one of the "china doll" engines off of ebay. I used the 66cc/80cc (no such thing as 80 cc). Everything you need to get started comes in the kit except - the bike (I used a Micargi steel frame Touch), gas and oil. For gas I use 93 octane and use 100% synthetic oil which you can also buy on ebay for about $40 per gallon. This will last a long time. When breaking in the engine use a 16 to 1 ratio as to oil. After break in (about 2 gallons of mixture) change to 32 to 1 mixture. Other may different opinions on the ratio.
If you want to go fast and be safe, I recommend the following: make sure you have front and rear brakes on the bike. Insure they are good quality. I use Tekpro. Make sure the bike is of steel construction. Upgrade the carb and exhaust to get a faster bike. You can also port the intake and exhaust. See youtube for doing this. They have some good videos. By doing these upgrades and after the break in period you should be in the 40+ mph range. Some of the speed will depend on road conditions and the total weight of the bike and your weight.
By the way no directions come with the engine kit. Again look at youtube for videos as there are many good ones there. It is pretty straight forward and is you are mechanically inclined at all, it should only take you about 3-4 hours to assemble the engine on the bike after watching the video a few times.
Update: You may also want to upgrade to a manic mechanic rear sprocket. I do not trust the sprocket that comes with the kit. It uses the spokes to turn the rear wheel The manic mechanic uses the HUB on the rear rim to turn the rear wheel.
Play safe.
