Problem with Speedo instrument flickering

In my experience you need the lightest lubricant possible. I used to suffer with the wobbly speedo needle and tried various solutions. What worked for me was removing inner cable and washing the outer clean by pouring petrol through it. I then lubricated the inner wire with some very thin lubricant designed for cycles, a sort of dry lubricant once applied. End result has been a rock steady speedo.

I bought this after talking with Vintage British Cables . Apparently this is what they lube their cables with.

Lorenzo said:

what kind of lubricant? WD40? engine oil? grease?

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I've used ordinary grease but don't grease the last 6 inches or so at the upper (instrument) end I suggest that after replacing the inner cable you pull it out a few times and wipe any grease off the inner cable.

Lorenzo said:

what kind of lubricant? WD40? engine oil? grease?

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Sewing machine oil.

Nortoniggy said:

In my experience you need the lightest lubricant possible. I used to suffer with the wobbly speedo needle and tried various solutions. What worked for me was removing inner cable and washing the outer clean by pouring petrol through it. I then lubricated the inner wire with some very thin lubricant designed for cycles, a sort of dry lubricant once applied. End result has been a rock steady speedo.

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can you please show what you used?

I was under the impression that drive cables should not be oiled or greased, but lubricated with graphite.

Lorenzo said:

can you please show what you used?

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I have used both of these at various times.



They do say for chains but they work well on speedo cables.

I currently use the Muc Off one on some other cables. It seems to be just right for throttle cables particularly.

cliffa said:

I was under the impression that drive cables should not be oiled or greased, but lubricated with graphite.

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Not sure why? I replaced mine 5,000 miles ago. As LAB said, I put a light coat of usual automotive grease around the cable. Used the same in the speedo drive on the axle. Avoided the top 6 inches of the cable, to avoid getting anything into the speedo unit. Working fine, so far.

Mart UK said:

Not sure why? I replaced mine 5,000 miles ago. As LAB said, I put a light coat of usual automotive grease around the cable. Used the same in the speedo drive on the axle. Avoided the top 6 inches of the cable, to avoid getting anything into the speedo unit. Working fine, so far.

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Presumably for the same reason you shouldn’t use grease or oil in locks. - They will eventually dry out or create a dirty slime. However it seems most folks just use grease anyway.

cliffa said:

I was under the impression that drive cables should not be oiled or greased, but lubricated with graphite.

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Watch out with graphite aerosol spray, that stuff gets everwhere and seems to take days to get it out from fingerprints....gotta becareful not to commit any crimes for a few days after, the rozzers will be all over you in no time....

Tornado said:

Watch out with graphite aerosol spray, that stuff gets everwhere and seems to take days to get it out from fingerprints....gotta becareful not to commit any crimes for a few days after, the rozzers will be all over you in no time....

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I use a puff bottle ( small ) of bicycle graphite . No pressurized sprays .

Oil should never be used on speedometer cables. It will eventually corkscrew up the cable and contaminate the instrument. It also does not provide the cushioning needed to prevent cable slap and a flickering pointer. Graphite should be avoided. I recommend AGS Sil-Glyde. It is designed for lubricating speedometer cables. It is unaffected by heat and stays put. The lubricating compound and brake lube are the same product, just different packaging. Thick grease would be an alternative. Always wipe the top 6"-8" of inner clean of grease or risk it contaminating the instrument.
Inner cable protrusion is critical, especially with the later Smiths MK2 magnetics (typically the black faces). 9/16" protrusion will damage a magnetic instrument. I consider 1/2" to be maximum. Too long an inner cable is the most common cause of instrument failure.