Just got my new huasheng 142f 49cc. As far as I'm aware this motor doesn't have a rev limiter, and the gearbox that came with it is only a 5:1. I'd really rather not blow my motor up so either I need to install a rev limiter or I need a good tachometer. Any suggestions? I'm sure the tachometer will be easier to install but the rev limiter is in the long run because I don't have to think about it.