Posted by a reviewer on Amazon

Directions are a bit funky but after some trial and error i got the device to measure the rpms of my twocycle vespa

Posted by a reviewer on Amazon

No directions for battery replacement and case is not constructed to allow easy battery replacement

Posted by a reviewer on Amazon

I chose to leave a review because i was planning on getting another one for a different bike and saw the bad reviews

Posted by a reviewer on Amazon

Not sure i trust it

Posted by a reviewer on Amazon

You can set it to count once or twice per revolution or every other revolution depending on when the spark plug fires typically once per revolution

Posted by a reviewer on Amazon

My main complaint is that the decription says replaceable battery and while that may be possible it does not appear to be made with that in mind and no i was not reading the wrong description it says this for both models

Posted by a reviewer on Amazon

I had to pry the back off with a fine blade jewelers screw driver to get to the battery which is a large button cell mounted on the circuit board with hot melt glue

Posted by a reviewer on Amazon

Installation of meter is trivial