Brief History: Smiths ATRC Tachometers

Brief History: Smiths ATRC Tachometers

Earlier this month I was fortunate enough to get my hands on an original (and rare) Smiths ATRC tachometer

I admit I was very lucky but this ATRC tach wasn’t my first unit I came across; in fact, it happened to be my second..

Foolish me I traded my first tach a few years back and I still regret it

Lucky I have a new unit here..

Today I wanted to share with you my new prized possession and also cover some brief history on these rare and also interesting tachometers

I hope you can follow along..

ATRC History

Smiths Instruments Vintage Catalog

Smiths instruments of England produced many types, sizes and models of both speedometers and tachometers for scooters, motorcycles and vehicle applications during the 1930s through the 1970s

With a large range of instruments to offer, Smiths also offered a range of motorcycle tachometers suited for racing and competition use

ATRC units are extremely accurate, reliable and very expensive

With an all aluminum machined housing and a spindle rotating on twin ball bearings you can feel confident that an ATRC tach would offer you winning results

No wonder ATRC units are known as the “Rolls Royce” of gauges and instruments

What is "ATRC"?

ATRC

ATRC stands for “Auto Tempo Racing & competition”

Auto Tempo happened to be the name of an old gauge company that Smiths acquired in the 1920s

Auto Tempo manufactured gauges use the “Eddy-Current" principle which Smiths later took into production during the 1950's-1970's 

Click here for more info on the “Eddy Current Principle”

Applications

Smiths ATRC Tach Mounted

With Smiths ATRC tachometers being suited for racing and Competition use, each gauge was supplied as “universal” based off a specific motorcycles specification

Smiths offered ATRC tachs in a clockwise and counter-clockwise condition with variations in RPM range and also gear ratio to fit most applications

All ATRC units measure 3” in diameter with a satin chrome plated bezel to limit “glare” to the rider

Extreme care must be taken into consideration when mounting an ATRC tachometer

Smiths offered anti-vibration mounting brackets that consisted of 2 round stamped steel plates while the center plate is isolated on a thick rubber o-ring / rubber band to help prevent vibration

Value

Smiths ATRC Tachometer on eBay

The value of an old Smiths ATRC tach depends on several key factors

  • Model
  • Condition
  • RPM range
  • Gear ratio
  • CW or CCW

Considering that these instruments are very expensive, you will tend to find ATRC units “complete” and usually in working order

I’ve seen ATRC tachs go anywhere from $500-$2,000(USD) on eBay and forums consistently

Although ATRC tachs are very rare instruments I do see ATRC tachometers for sale every now and then on eBay throughout the year, however finding an original mounting plate can be more challenging!

Thanks for reading

Thank you for reading today’s post

I hope you have found some of the history and information above on old Smiths ATRC tachs useful

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Ride safe!


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