Hi all

Just wondering if anyone has used an inductive tach to measure rpm on things like leaf blowers and line trimmers

I just bought one like the attached picture and am having some problems working out speeds.

I managed to find that setting 2 is for 2 strokes, and setting 1 for 4 strokes. I worked this out as setting 1 gave idle at 1740 rpm for a Briggs Classic 35, and setting 2 gave idle of a Ryobi trimmer at 2100rpm (about right)

My issue is measuring full speed rpm on 2 strokes. If I go full throttle on the Ryobi, the tach goes up to 7000 odd rpm. In the Ryobi manual (see photo), it says 12000 rpm maximum. Without the trimmer head (split shaft) it will do about 10,500 rpm, I can get it out to 11800 by leaning the mix, but it runs awful with the head back on.

It said full throttle (governed) on Briggs was 2800 rpm.

I assume the max rpm numbers Ryobi supply are off - max possible speed maybe. I bought the tach so i could simply dial in the high speed jet precisely to the required rpm, but the numbers don't add up.

Any advice would be appreciated

Regards
Tyler

[Linked Image from i.ebayimg.com]

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