Yes, it works ok. A little slow on the updating time. WOT measurement takes a few seconds before it settles down and it's not really high precision. I'd guess it may be good for +- 500RPM or so at high speed. I can confirm that it will read above 10k, so no problem there...plenty of maximum for a saw.
You can really see the screen in this video, but it's working on my 066. Just had to wire a black ground to a starter cover bold and then wrap the red wire around the spark plug wire.
For the money it's good. But if you used one of these regularly, you'd be better off buying a higher quality unit.
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