Yes it's a 5.8 Morini motor. It's been trouble free for a while now and it ran great in the sand. I rode it that day over 70 miles out in the Mojave Desert. With a 47 tooth sprocket it easily hits 40+mph. Future plans are to install a 9.4hp cylinder.
Absolutely, in my case, I bought a complete damaged engine for 50 u$s, and then fully rebuild it. I´m amazed by power of this little engines, they not only have very low end torke (it can almost climb everything), with a 44 tooth sprocket my ride can reach speeds of 70kph, too fast for a bike .
I´m worried about the position of the chamber in your bike, didn´t get your leg roasted by the hot piece of metal?
Not at all. The pipe has a heat shield that's has an 1/8" gap between the pipe and heat shield. I ride in shorts all the time and haven't burned the inner thigh once. I even rest my bare leg on it when I'm riding. I'll see if I can dig up a picture.