I can tell you a relatively easy way to make a pickup that will run ANY kind of tach….if you have some electrical/cobbling/fabrication skills. Find two really tiny magnets; epoxy then on the outside of the flywheel 180 degrees apart (JB Weld works great. I’ve buzzed sled motors 11K+ and they never came off). Go to a parts store and look through their assortment of cam/crank position sensors and find one that you think you can mount to ‘look’ at your magnets that has two wires. My weapon when I was doing this on the clutches of open-mod drag sleds for memory tach or other monitoring eq. was one for a late ’80 GM 2.0 four-banger (think:Cavalier). Get it mounted ‘looking’ at your magnets, ground one wire, the other goe to the tach. Set your tach to "4 cylinder" four stroke (two pulses per engine rpm). It’ll work jolly good, trust me. I’ve done this with Autometer memory tachs running off cordless too batteries and/or moped batteries if you want something high-dollar and really accurate. This will work with ANY sort of tach. Honest…
Jim
I say "pardon me" a lot. I had a 20H, then raced open mod sleds.
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