Here is how you install hour meter on ATV. It is usefull to monitor service intervals.
On back is good user manual. It is really simple to install it.
First I removed ignition coil, because it was easier to wrap wire on ignition cable. Then wraped wire 5 times and secured it with zip tie. Also I wraped it with tape. Make sure you wrap wire as close to igniton coil as you can. That means you will avoid heat from engine.
I mounted on dash, that was the most suitable place for it.
You can mount it on gas engines, like lawnmovers, atvs,motobikes…
How it works?
The ignition cable inducts electricity on wraped wire. That is why you need at least 5 turns.
Here is nice video how igniton works:
And more scientific explanation of electromagnetic induction between 2 wires