Smiths speedometer

[morris]

Have a mate with a Shelby Cobra. These cars normally have a counterclockwise speedo to match the counterclockwise gearbox output. His car has a Smiths clockwise speedo so don’t work. It seems that there’s some kind of small gearbox available to reverse the rotation of the cable. Does anyone know of a Smiths instrument specialist who may  be able to help him out?

[berger]

this may be of no help because of risk of loss or postage cost but on the other hand it might help to know that a small Nottingham / England shop called gaggs reversed my A65 magnetic to make it work on the A7 and also geared it to 3to 1 to match the oil pump drive.

[terryg]

The speedo/tacho part of Gaggs became Chronometrics UK, Russell Smalley is the man. Use ‘search’  to find more details; there’s reference to them/him in the Trusted Suppliers section.

[beesa71]

One source would be;

http://www.speedograph-richfield.com/html/minature_gearbox.html

The ‘standard’ Jaguar (I recall) Unit/application for the right angled drive on the back of the instrument wasn’t reversing (I don’t think the one I have is) but I’ve always assumed such we’re available. That type often available on Ebay.

Paul.

[olev]

Hey Berger,
Old thread, but what cable did you use on the magnetic speedo. Was it a standard chronometric cable or magnetic?
Did the nut fit onto the speedo head? any issues?
cheers

[berger]

hi olev you have to use the magnetic cable on a magnetic speedo or rev counter because the nut on this cable is longer, the inner on a magnetic cable sticks out 9/16ths and has a longer nut, the chrono sticks out 7/16ths with the shorter nut, many years ago when i knew nothing [ still don't ] i cut the boss down on a magnetic so my chrono cable would fit. you have to be careful because too long an inner will damage the speedo's , so i was told.

[limeyrob]

I believe the treads are all M12x1 because Smiths went metric early on. But as said, nut lengths and inner lengths from the collar vary.  There is some wriggle room as you can change where the collar sits on the inner, its just pressed on.

[berger]

rob the only wiggle room you get when fitting a chrono cable to a magnetic speedo is the nut hanging on by one thread or maybe two

[berger]

piccy

[Rex]

And a Chrono takes a big dislike to being rammed with a magnetic speedo cable.