Anyone know anything about Auto Tempo 5" speedos?

roy the mechanic

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5inch speedometer

From my experience [35 years restoring and racing] Talk to Ashley Pople. He has been a source of help and encouragement for most of this time. Whilst Joe Shaw worked at Auto tempo, he must be retired or passed by now[nothing personal here] just chonologically. Be lucky out there, Roy.
 

nkt267

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My understanding is that of the real 5" clocks there were the two variations you mention
I have come across an Auto Tempo clock that needed the knurled knob angle drive fitting to it and ther was no room to fit it. I had to make a spacer piece so that it would work. 3 types then?:confused:
 

clevtrev

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The chronometric mechanism is a standard Smiths unit (the weight of the balance wheel varies for 80 120 or 150 MPH speedos), but the Shadow clock and Series D clocks have a different aluminium chassis. Instead of a threaded protrusion they have a hole into which the right angle drive unit fits.
Paul,
The Chronometric, hence the name, was made by Smiths, under licence from Jaeger of Paris, France. Where does one think metric came from ?
http://www.vincentownersclub.co.uk/photos/showphoto.php?photo=3138

I have posted here the early type of drive box, along with the commonly known and a modern BMC unit.
As you can see with the early type the drive spindle is attached to the chassis of the unit, and the drive box is clamped on to the chassis, the spindle stays in place.

One needs to realise that as the unit is metric, ALL of it and everything is metric. So don`t believe all you read in some books. In KTB it tells you that the holding bolts of the 3"unit are 0BA but 6mm wil fit. NO, the thread is 6mm and an 0BA nut will fit. Otherwise someone will have to re-write the standards and tell us that the BA thread angle is now 60 degrees, which is as written in KTB. Also the thread by which the cable is mounted on to the Speedo is M12 x 1mm pitch. So much for `There are no metric threads on your Vincent`.
Some also would like to know about the screw that fixes the case to the frame on the 3"unit, it`s M5 x .75 pitch.
 
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Paul Ennis

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Yes Trev, they are as metric as frogs' legs :rolleyes:
The M5 x .75 screws are French Standard Thread, but how about the face fixing screws? They are M2 x.45........I can't find any table listing these.
Paul, STA. (screw thread anorak :eek:)
 

clevtrev

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Yes Trev, they are as metric as frogs' legs :rolleyes:
The M5 x .75 screws are French Standard Thread, but how about the face fixing screws? They are M2 x.45........I can't find any table listing these.
Paul, STA. (screw thread anorak :eek:)
I have a tap, M2 x .45..... if you need one..:) I think they are `Extra Coarse`
 

vapide

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BTW I described the Landrover gearbox, possibly the only version still available, as being even clunkier than the Smiths BG2410. I by chance had a look at the the one being currently supplied the other day, and it turns out to be an almost exact clone of the Smiths BG2410, except that it is marked "Jaeger" and "France". Which may mean it is actually the same thing, Smiths and Jaeger having a complicated history (Smiths bought out the British branch of Jaeger many years ago, and produced under both names, and anyhow Smiths doesn't own Smiths any more ).
 
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