What an addicting Hobby. I am now riding my second Build a Nirve Scull series hand built cruiser with 68.5 cc H2 angle plug engine with a 3 speed interplanetary hub and jackshaft assembly, milled heads expansion chamber. Gave up my 42mph (new Top speed 38.6) for power needed to climb on Pleasanton ridge about 800 ft above sea level where I live. A dependable bike!!