New member with '66 CL77

[Glenn-N]

Went for a cold but sunny ride today, unfortunately for the first time my speedo became erratic.
At first it sometimes bounced from 20 to 60mph and back, but after a while it kept going around 80mph and at that point I noticed the needle was damaging the face plate.
Had to stop and disconnected the cable to ride home.

Is this a common issue? Bit of a shame, was such a nice speedo.

[LOUD MOUSE]

You may want to remove cable and clean then lube with a thin coat of white grease .
At times I;ve needed to put 30 weight machine oil (not detergent) in a cup them set the cable area of the speedo in the oil over night then place that area on a rag to remove extra oil after you have run the speedo with a drill. (use a cut off end of a old cable). .........lm

Went for a cold but sunny ride today, unfortunately for the first time my speedo became erratic.
At first it sometimes bounced from 20 to 60mph and back, but after a while it kept going around 80mph and at that point I noticed the needle was damaging the face plate.
Had to stop and disconnected the cable to ride home.

Is this a common issue? Bit of a shame, was such a nice speedo.

[Glenn-N]

Thanks Ed.

Cleaned + lubed the cable and tested with drill, no success.
Then sprayed a small amount of silicon spray in the bottom drive on the speedo, and the problem seems solved. Just such a shame it kinda ruined the faceplate.

Anyone here who has this replacement installed?

https://cb750kfour.com/products/cl77-sc ... plate-decl

[LOUD MOUSE]

Good deal. ...........lm

Thanks Ed.

Cleaned + lubed the cable and tested with drill, no success.
Then sprayed a small amount of silicon spray in the bottom drive on the speedo, and the problem seems solved. Just such a shame it kinda ruined the faceplate.

Anyone here who has this replacement installed?

https://cb750kfour.com/products/cl77-sc ... plate-decl

[DJM]

I had an almost identical problem with my CL speedo some years ago.

It was fine when I first restored the bike, (in 2008) although the bike (and hence the speedo) had stood unused for I would guess about thirty years.

A while later it developed the same symptoms that you had, although perhaps not quite as severe. Also I was getting a screeching sound from the speedo and the needle was very slow to return to zero when coming to a standstill.

Cured the problem by very lightly lubricating the drive end of the speedo itself and greasing the cable, again sparingly.

I also suspected that the inner cable might have been a bit too long for the outer, rather than trying to shorten I put a small 'O' ring inside the cable top nut/ring between the end of the inner cable and the instrument itself, this had the effect of lengthening the outer cable by a couple of millimetres.

The problems all went away and haven't returned.

I'm not sure that the problem you have with the needle marking the speedo face is related.
I've seen this before but it suggests to me that the mechanism of the instrument isn't sitting square to the face, hence the contact between the end of the needle and the dial itself.

Can't really suggest another cause for this as your speedo looks really nice and in great condition.

Go for the fascia overlay by all means but remember that you have to open and reseal the bezel, in itself not that simple to make a good job.

While you have the speedo apart,(if you go down that route) you might see why the needle has been contacting the face, be sure to let us know what you find!

Good luck.

[Glenn-N]

Thanks for the info. I had it opened by a pro 2 years ago to clean the glass.

While I tried the speedo with the drill I also heard the screeching sound.
I could see the needle bouncing up and down, it was vibrating hard, that's why it touched the speedo face.

After I slightly lubed and retried it worked fine and didn't bounce anymore. Alignment seems fine.

I have a spare speedo (possibly for future restoration) which I never used or installed, it also has very fine marks on the dial (top) from the needle. Decided to try it with the drill and had the same problem, screeching and jumping. Lubed it the same way and it works fine.

This one also needs to be opened in the future since the glass has stains on the inside.
PO who cleaned it left some marks.

[DJM]

Hope your speedo turns out as well as mine has done.

Needle is rock steady at any speed and drops straight back to zero when stopped also, it seems pretty accurate too, certainly within the levels quoted in Road Tests when the bikes were new.

For a fifty plus year old piece of kit it's amazing.

I have a 'spare' speedo showing only 19 miles on the odometer, common sense tells me that I should sell it on to a deserving case but, knowing my luck, if I did that the one on my bike would fail the next week.

I have a workshop full of stuff in that category!

DJM