Instruments

I pulled out the speedometer and tachometer a couple of weeks ago to try to decide what to do about them.

They are both the original, stock instruments that came on the bike. The speedometer was in bad shape. It was weatherbeaten, the pointer was broken off, and both odometer assemblies were crooked in their windows. The tach looked a little better, but I seemed to remember that it was very jumpy the last time I rode the bike.

I had several choices regarding the instruments: Aftermarket reproduction units are apparently available. There are also a number of outfits that would rebuild these units, or accept my units as cores, and sell me rebuilt ones off the shelf. The research I did showed that neither of these was necessarily a bad choice.  

The other option was to try to rebuild them myself. Since the this option is more in keeping with the spirit of the entire project, this is the route I chose.

  It turns out that one of the most difficult steps is the first one:  getting the crimped bezels off.  The sources say that if the bezel is carefully pried off little by little around the perimeter with a small screwdriver, that the bezel might be reused.  Once I got the hang of it, it wasn't too bad.   When I was finished, those bezels didn't look like anything I'd want to reuse.

Most of the pictures that follow are of the speedometer. The tachometer is identical inside, except that it doesn't have the odometers.

  There is a triangle-section rubber seal between the bezel and the glass, another rubber seal under the glass, and a circular mask piece that hides the space at the edge of the dial, but allows light from the internal bulb to illuminate the dial.  The rubber seals were hard and brittle, and basically fell apart on disassembly.

Undoing the three screws on the back of the case, the mechanism can be lifted out. When I did that, the main odometer assembly fell out onto the table.

The internal mechanism can look a little intimidating at first, but it is really pretty simple.