Got governor issues on my BN.It has a mag, so I've been limited on what I can use for a tach to got the engine speeds governed right. When I first got her running last spring after a rebuild (pistons sleeves, crank ground, head done over . . .) I set it up by ear. Just recently, I had a friend come over with his wheel/tach and ran it off the belt pulley shaft. Results were a little erratic. Since then, I FINALLY found a laser tach for less that the cost of a used car, and have run a better check. What I've got with a warm engine is a high idle (no-load) of about 1465 versus a target of 1540. I can get the low idle down to about 540 (vs. a target of 525) but that tends to settle back in just under 600 after it's been run up to speed and brought back down. Problem I've got with the high idle is that I had to run the adjusting screw almost all the way down to get to where I am. Didn't seem right at the time, but it hasn't been over-sped, and it seems every other I've tinkered with leaves some room to adjust up or down when it's set right. It's down so far, I'm not sure I could wring another 75 rpm out of it by tightening it down any further. (Inside of the governor is clean with new spring and bearings, and the governor-to-carb throttle lever connection on the left side is correct.) As far as low idle, if I keep a little pressure on the throttle-stop screw when I'm adjusting it, I can get it down to about 530-540. I'd be happy with that, but if I leave her set after taking that pressure off, or run it up and back down, she settles in, as I said, to about 600. That, and the bottom 40% of the throttle control back at the seat does nothing. It doesn't do a thing until you're almost halfway up, and tops out one notch below the top end. (FWIW, my SuperC is the same way since I had to replace the old Carter with a new-fangled Zenith. I have the same Zenith on the BN). What am I missing? I'm thinking the throw of the actual throttle lever on the Zenith is enough different that that's just the way it's going to work. I'm more concerned, though, about the extreme adjustment on the governor to get to where I am. I'd really like to get that backed out to a more middling range while getting the rpms up to where they should be. About all that's left that I can think of is the geometry of the rod that runs from the lever at the seat up to the governor, and perhaps the springs at the block where it connects up to the governor. Just not sure how effective that would be. Any thoughts, experience, ideas?
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