Originally Posted by 2door
Actually it was the name of one of the earliest 2 stroke engine kits. The company that imported it to the states called their kit "Happy Time Bicycle Motor". The company, or at least their name for the engine is gone but Happy Time, or HT stuck and it's become synonymous with the Chinese 2 stroke, in-frame engine.
I think that you're joking but it comes off like you know what you are