After lots of mods, and months of adjusting and tuning I finally broke threw the 40 mph barrier... 43.5 mph. I was riding on Lake Mead Blvd. side by side with traffic and wasn't looking at the speedo so I didn't even know I broke threw until I got home and was checking the stats on my trusty Iron Horse bike computer. It tells me all kinds of info like date & time, air temperature, ride time, miles ridden, compass heading, average speed, average ride time, calories I didn't burn pedaling, and of course max top speed.
I'm running a heavily modified 66cc China engine with single speed direct drive and a 36t sprocket on an adaptor. I use Opti 2 oil mixed at 100:1. The bike and engine have over 800 miles on them. Next comes a shift kit and than I'm going hunting for 50 mph...