Got tired of hearing my original mechanical speedometer whirr … grind … whirr … clack … no beeping though so I replaced it with one of those new fangled GPS speedometers, complete with accessory antenna. The good, it works, it is backlit (changed it to green), and installed very easy. The bad, it restarts my odometer count as like any odometer net mileage can’t be changed to falsify mileage and it only shows total miles in whole numbers (at least by default).
Was at 19,884 miles when i started the conversion. Hit 4,000 miles on April 20, 2023.
So I didn’t really care for the rectangular container for the voltmeter & haven’t been able to find a round digital one of the size and type I want. So … what to do? Make your own case, came the reply from nowhere. So I did.
Started with a previous bad voltmeter, took the screws out, took the guts out, took a drill and a leatherman to the front of it after tracing the bottom of my voltmeter with a sharpie, and then installed. Note that a sharpie is not the best tool for marking on plexiglass.
So the original analog meter got stuck about 16 or so volts above actual (or above something) after the first test ride. Replacing it with this one, once I figure out how to mount it in a secure and stable way. Would also be nice if I could get consistent readings across multiple electric volt meters but there seems to be a consistent difference between 0.3 v and 0.7 volts.
So I topped up the batteries last night to 81 volts and then took it on an 8.4 mile ride through part of town this morning – presuming the odometer is correct. After getting out of the neighborhood it was a mile downhill at 45 mph (mostly coasting assisted), then about 2 miles at 45 mph with 3 stop lights to destination. The only difference is that on the way back it was back up the long hill.
What i noticed while returning home was that the loud squeal I was hearing from the front of the bike was the sound of the speedometer connection with the cable from the front tire spinning rather hard and vibrating like crazy. Will check it for alignment (unplug cable and replug basically) to see if it will fix.
Anyway, voltage leaving was 81.0 volts, voltage after the 8.4 mile ride was 77.3 volts. This is a difference of 3.7 volts, which comes in at 8.4 miles / 3.7 volts = 2.27 miles / volts. Roughly a range of 38.59 miles with a low cutoff of 64 volts. Need try longer, just not keen on finding out the hard way i couldn’t quite make it home.
So one of the first things I had to do after purchasing the bike (from craigslist) was to fix some things that sorta needed it. Like the tachometer. These aren’t made to be taken apart and put back together for some reason. Note the silver holding ring on the bottom left – it has to be pried off. Or cut off. Even if pried off there’s no guarantee you’ll get it back on the same way. Once apart though the tach was easy to fix. Mine was missing one of the screws that holds the face to the gear drive behind it so the tach just jumped all over the place. Fortunately I’ve collected a fair number of computer related screws over the years and was able to find a couple that fit. Easy fix. Except putting it back together. After reassembling it properly (except for noted holding ring) I put the holding ring back on & then silver foil taped it in place. This has been working since April 16, 2011.
