Smiths Chrono speedo cable fitting

[UncleD]

Evening all,
1958 Super Rocket, Smiths Chrono speedo.

I purchased an aftermarket speedo cable through British Spares in NZ.  The cable received is UK made and the correct length.  The gearbox end fitting is fine and the speedo end appears to be the correct size BUT... the coupling nut is not deep enough to connect with the thread on the speedo.

British Spares say it fits several similar speedos...but there is no way I could get the thread to bite.

Has anyone experienced this?

[UncleD]

This is the speedo.

[UncleD]

The underside.  It has been suggested to me that there is a 'long and short nut versions' as well as that it may have a magnetic guts (rather than chronometric).  Any suggestions how I solve this?

[JulianS]

The face number of your speedo does not look like A10, I would expect 1440 or close rather than 1620.

The connection looks more like magnetic. It is not a chronometric connection - see photo which is the back of the one from my A10.

Can you match your old cable length with a new one for a magnetic speedo?

[muskrat]

G'day UncleD.
I put one of those cheap Indian speedo on my Cafe. I had to get a matching RE cable and modify the bottom end to fit the gearbox.
Cheers

[trevinoz]

I have a Chronometric which is calibrated 1000 and was allegedly from a Police bike in the 70s.
It has the magnetic type nipple.
I used it on my T65 for a while when the magnetic instrument was being repaired.
The police used the Chrono rather than the magnetic and had them calibrated regularly.
This is N.S.W. I am referring to.

[Rex]

The underside.  It has been suggested to me that there is a 'long and short nut versions' as well as that it may have a magnetic guts (rather than chronometric).  Any suggestions how I solve this?

Magnetic guts would have a central cable entry while yours appears to have the off-set Chrono entry.
If I recall the Chrono cable has a shorter end to fit in the mechanism to prevent undue thrust/wear, so maybe someone's sent the wrong inner or outer for your bike?

[trevinoz]

Just buy a magnetic type cable.

[UncleD]

After chatting with a couple of experts in QLD and Canada, it turns out there were some later Chronos (around 1962) that had a magnetic coupling but Chronometric mechanism.

Having a cable made (with correct length inner cable and longer outer coupling) and posted from Canada (Vintage British Cables)  for around $50AUD.