I have repaired several with success. What I have found it is more the lubrication of the clock that causes it to not keep time and often stop. You can tell this by the sweep hand just toggling in position, sometimes it will not move at all.
To disassemble the clock:
- Make a jig to disassemble/re-assemble.
- I made a jig by using bondo on a plate with a center hold cut into it with a rod screwed on the back side.and mounted it on my lathe. Cover the clock with cellophane and press into the bondo with the lathe. This way it is centered perfectly and creates a good support structure for the fragle bezel. Before the bondo hardens cut the excess off so you can see the edge of the crimped part of the clocks bezel.
- You need to make a tool that is like a mini crowbar that has the shape of the rounded surface of the bezel, so you can have a solid mount and can pry the bezel off with good control.
- Mount on the lathe and pry the bezel crimp open and carefully remove the bezel.
- Once you have that removed you can undo the nuts on the back side of the clock and push the clock out. You will see the internals of the clock.
- On the back you will notice a clear plastic cover and three nuts to remove to open the clock up. Once you have this off you will see the circuit board.
- Apply 12 volt power to the clock to see if the flywheel swings. If it does it is the lubrication. Then remove the circuit board. Be very careful as there are what I would call micro wires that are the coil turnings to make the flywheel toggle. (If it does not swing it is the circuit board. I have not had one of them bad to date, so I do not know how to diag the board).
- Remove the hands and the face plate. Be careful as the hands can be very brittle.
- Remove the front piece of the plastic casing.
- I placed mine in a sonic cleaner with safety clean. After about 20 minutes, I clean off by using air at a low pressure to clean out all the solvent. Be careful to use low pressure as you can blow the tiny gears off.
- Lubricate the mechanism with a synthetic watch lubricant I got on line, only use enough to wet the mechanism.
- Use a solvent such as lacquer thinner to take the paint off the bezel. Make sure it is nice an clean. You will repaint once the clock has been reassembled.
- Then reassemble in reverse order
- When I reassemble I place it on the lathe and use another tool that will round over the edge of the bezel. I also use RTV to assist with the sealing of the bezel so when it gets wet it not fog up.
- I then will use painters tape to protect the glass. Carefully press the painters tape to the edge of the glass and use a fresh razor blade to cut the tape so it is a good clean cut an only the bezel is exposed. Then use tape to cover the barrel of the clock. Clean the bezel with an grease cleaner with a lint free cloth. Pick a nice satin auto paint and lightly spray for an even coat. Usually two coats work. Carefully remove the painters tape. Let the paint dry and mount back on the bike.
- I would also insert a switch in line with the power of the clock so you can turn it off when you are parked for extended times.
Hope this helps.