Shakedown period : Clock whine.

just over 100 miles into the running in period, and the weather turned a little colder, and my clocks began to whine.
Initially, I thought that I was in danger of suffering a gearbox failure, as the sound was so similar to gear whine, but louder, much louder.
Using the mark-1 ear device soon led me to the clocks as being the culprit though.
Initial diagnoses were complicated by the speedo and tacho having slightly different pitched whines, and the fact that both would exhibit the behaviour at different times.
the tacho starting its whine at circa 3500 rpm, and not stopping until the revs had dropped below 2000, and the speedo starting it’s whine at circa 30 mph.
Additionally, the whine does not vary in pitch as the revs, or speed rises and falls.


A swift trip to google showed that this is not uncommon with old mechanical speedo and tacho devices.
The modal advice seemed to be spraying some type of lubricant into the clocks through the junction where the cable attaches. This has the advantage of not having to remove the clock assembly from the bike, so I tried with a can of WD40.

Initially, this had some affect, lessening the whine, but it was still there, and after 20 miles, came back full force.

So next, I removed the clocks from the bike, and put together another assembly with some “spare” items.
This seemed to be a good time to build up another complete binnacle with wiring and bulbs, so I needed some parts, as some previous butcher had cut the connectors from the spare clock harness I had.

Before embarking on this path, I tested the spare clocks using an electric drill running backwards / anti-clockwise. No whine, which was good.

I ordered some 2.8mm connectors from aliExpress, as a set of various connector sizes and shapes. The upside being that they were around a tenth of the price of similar items from Kojaycat, the downside being that all the plastic connector housings were black. no matter, I can mark with some white paint or stickers. (I ended up using liquid paper, which was effective)

The first step was to measure the free length of my GOOD wiring, to see if I had enough free wire left after the butchery. I did, so only one wire extension was needed in the main cluster of wires.
The tacho side group needed a complete remanufacture, using the correct wire colours harvested from my birds nest of old looms.

Having assembled the alternative binnacle, and taped up the shattered spare base, I fitted it to the bike and took it for a ride.
Disaster and mayhem!
They whine, if anything louder than the others.

More offboard testing showed that all 4 clocks spin up and sound great on the drill test rig, but whine when connected to the bike.
This would seem to indicate that the problem is elsewhere, perhaps the cables, but after much greasing, oiling, and rerouting, this proved not to be the case. The whine is most definitely coming from the clocks themselves, but only when connected to the bike.

Ultimately, I have cured all 4 clocks of their whine.
2 drops of 3-in-1 oil, administered with the clocks upside down, and allowed to penetrate overnight did the trick.

this works I think because the whine is not being generated inside the mechanism, but within the static threaded alloy stub, and the rotating cable socket within it.
The oil doesn’t need to go inside the clocks, just between the moving parts of the external mechanical connector.

So the replacement clocks are fitted because they are a little more accurate then the others, and look in better condition. The electronic digital tacho will be removed from the handlebars for the final build, now that the accuracy of this tacho has been determined.

This pretty much concludes the shakedown period. I have so far completed 300 miles of running in and the bike feels taught and new. If I nudge the handlebars at 80, I can feel it wanting to go into the classic LC weave which is reassuring, and quickly damped out with a lighter grip on the handlebars and a bit of a knee clench on the tank.

Next step is to tear it all apart again for powder coating, and reassembling with a new set of bodywork prepared and painted by Mark Cordwell.

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