Not the Spandex kind…
I noticed recently that a couple of manufacturers are offerning GPS speedometer sensors for electronic speedometers. Kermit has been without a speedometer since we acquired him. The 2-1/2″ Drag Specialties mechanical speedometer appears to work, but the cable was broken. The cable was broken because the cable was too short for where it was mounted and did not allow a generous enough radius to it’s bends. I attempted to reuse it with a longer cable, but apparently the nature of the cable’s failure has it stuck in the back of the instrument.
I stumbled across a nice LED speedometer by Intellitronix that comes in, appropriately, green. More importantly, Intellitronix also make a GPS speedometer sensor. I had trouble finding it for sale anywhere, but I found that JEGS carries a couple of GPS sensors. Turns out one of them, the least expensive one no less, is the Intellitronix unit!
So, to simplify my ordering, I found a decent VDO speedometer and an Autometer chrome mounting cup, all from JEGS.
The dogs heralded the arrival of the FedEx guy and I got started as soon as I could.
Of course, the first thing is to ensure that the lighting is green. The speedo comes with red and green silicone caps for the backlight bulbs. I will probably one day replace the bulbs with LED versions, but for now, this is green enough.
The mounting location is intended to be temporary. At some point, I will fabricate a bracket to more properly center it between the handlebar tubes, but for now, I’ll put it on the left one.
The mounting bracket can accept a hose clamp and/or a pair of screws. I had no appropriately sized hose clamps, so I fudged it with a few wire ties and a single stabilizing screw.
You may note that the screwhead is chewed up a bit. Turns out that the handlebar “tube” is actually a handlebar rod. Threading the screw into it without the benefit of my tap set was a challenge.
Wiring the instrument is very simple, especially when running the lights and speedo on the same power. Three wires, power, ground, speedo in. I followed my usual color codes, orange for switched power, black for ground and gray for sensor.
It looks pretty good in place…
The GPS device is not weather tite, so I installed it in the trunk.
The unit has three LEDs, red for power, yellow for antenna data connection and green for GPS lock.
The first time, it took about 3 minutes for the GPS lock to come on. Now it takes about 5 seconds.
The default setting for the GPS unit is to provide 8000 pulses per mile. It’s pretty simple to set the VDO speedometer to match.
I have verified that it at least indicates a reasonable speed driving across the yard. We’ll road test it tomorrow and compare the readings to a Garmin.
While I was running wire in the trunk anyway, I connected the tail/turn/brake lights in the trunk, too.