I'm currently running two of them on different motorized bikes they are hour meter/ digital tach combination connected to the plug wire by wrapping a small lead wire around it...has a setting for either 2cycle or 4cycle use.
Hour meter is very useful to keep track of my breakin hours. The tach is accurate but has a very slow response time. What I mean is that engine revs indicated lags real time engine speed. Not a problem for my use cause I'm not pushing limits. A racer would have big problems with lag time. Once engine speed is held steady the tach is pretty close to correct (I mounted one on a Rebel equipped with a factory tach & they indicted about the same rpm at steady throttle. Under $20. on ebay, not a bad buy. I have one complaint, the digital readout is not lighted on mine and in cold weather the display is very dim and hard to read...on nice warm days no problem seeing. Rick C.
