SPEEDOMETERS UP TO 1964

SMITHS/JAEGER CHRONOMETRIC INSTRUMENTS. Powered by Create your own unique website with customizable templates. The S467/163/N is the 'model number' for the speedo - I have this sheet showing Smiths speedo applications to Ariels. The 1550 is the 'turns per mile', which equates to cable rpm at 60 mph. Smiths Chronometric Speedometer Serial Numbers. Speedometers Email Tel +44 (0) 1 SPEEDOMETERS UP TO 1964 Regarding Smiths speedometers a major change was made in 1964 Pre 1964 machines fitted the following. The larger 3” instrument was of the Chronometric type. This in reality is a two in one clock a speed recorder and a distance recorder.
Smiths chronometric speedometer serial numbers lookup

Regarding Smiths speedometers a major change was made in 1964

Pre 1964 machines fitted the following.

The larger 3” instrument was of the Chronometric type. This in reality is a two in one clock a speed recorder and a distance recorder.

The speed is calculated by the same principle as used in clocks and watches which gives very accurate readings. The distance is calculated by a series of gears and ratios which move the numbers round.

Type identification numbers on the dial start

S xxx/x/x OR SCxxxx/xx for speedo RC xxxx/xx for Tacho

The 2” speedo was of the magnetic type still used today.

A magnet which is close to a metal disc is rotated by the drive cable and “drags” the disc round with it. A pointer is fixed to the disc which shows the speed on a dial.

A hair spring retains the disc from revolving freely. Speed is recorded by the drag of the magnet against the restraining force of the spring.

Mileage is again recorded by gears.

Type identification numbers on the dial

Spectra plus sc keygen software

X 80421 OR SN31xx/xx for Speedo RNxxxx/xx for Tacho

SPEEDOMETERS USED FROM 1964

In1963 the British motorcycle industry approached Smiths Industries to manufacture a cheaper 3” Speedo as the chronometric was too expensive for mass produced machines. Note British government (Police etc) still used Chronometric instruments after this time as they were very accurate and reliable.

The 3” speedometer manufactured after1963/4 used the same principle described earlier.

Type identification numbers on the dial start

Smiths Chronometric Speedometer Serial Numbers Chart

SSM 3xxx/xx SSM 4xxx/xx SSM 5xxx/xx for speedo RSM 3xxx/xx RSM 4xxx/xx for Tacho.

The design of the smaller 2” Speedo was changed but the principle remained the same.

Type identification numbers on the dial start SSM 2xxx/xx Speedo RSM 2xxx/xx.

WE OFFER THE FOLLOWING SERVICES.

For Chronometric type we offer a repair only service by prior arrangement

Chronometric

With prices starting from £45.00.

Early 2” pre 1964 type X80421 SN31xx/xx speedo RNxxxx/xx Tacho.

A repair only service starting from £30.00

A full reconditioning with 12 months warranty +£120.00Late 3”starting SSM 3,4.5. RSM 3 or

Repair only service starts at £40.00

Full reconditioning with 12 months warranty £175.00

Later 2” starting 2xxx/xx Speedo or RSM 2

Smiths Chronometric Tachometer

Repair only service start at £40.00

Full reconditioning with 12 months warranty £89.00

The variety of speedometers fitted to the MGB is a common source of confusion, especially in relation to the fairly common practise of swapping O/D and fully synchronized transmissions into MGBs that didn't originally have them. This will consequently cause the speedometer and odometer to read too high or too low, not an ideal situation.

Smiths Chronometric Speedometer Serial Numbers Free

'Revs' in the table below referrs to the turns-per-mile (TPM) the speedo expects to receive from the transmission via the speedometer cable. The TPM of your speedo should be printed somewhere on the face, along with a serial number.
Any variation in tire size from original specifications will of course also have an effect on the accuracy of your speedometer. See the discussion on tires and tire sizes in the Service section of the Tech Library on this website for more information on this topic.
The NAMGBR also has a cross reference table from car numbers to speedometer serial numbers by Orin Harding. 208 hammerli pistol. [Ed. Note- this link seems to have gone MIA, so I've duplicated the table below.]
KMR reports that if you have a setup that doesn't correlate to any existing speedometer type, Nisonger can put a new faceplate on your speedometer, and recalibrate that way. Check the Directory section of this website to find a list of companies that provide Smiths and Jaeger instrument servicing.
Tooth count (transmission):

Smiths Chronometric Speedometer Serial Numbers Online

Thanks to Bruce Mills for scanning and submitting in this chart - it's a lot more complete than the chart I was building!
MGB Smiths Speedometer Range and Turns-per-mile (Revs) Reference Chart

MGB Speedometer Cross Reference Chart

by Orin Harding, NAMGBR
The information displayed here is from MGB Driver, the MG Mailing List, on the Internet, or other sources. The North American MGB Register assumes no liability for the accuracy, safety, or legality of these contributions. Any opinions expressed here are those of the contributors and do not necessarily reflect the opinions or policies of the North American MGB Register.
Start End
Car # Car #		Part
No.		Speedo
S/N		M/KPHTransNotes:
101 - 138400NotGermany
BHA 44786125/04MPHSTD
BHA 44786124/04AMPHSTD
BHA 44786124/00MPHSTD
BHA 44796125/05KPHSTD
BHA 44796125/05AKPHSTD
BHA 44796144/01KPHSTD
BHA 44806125/06MPHO/D
BHA 44806125/06AMPHO/D
BHA 44806144/02MPHO/D
BHA 44816125/07KPHO/D
BHA 44816125/07AKPHO/D
BHA 44816144/03KPHO/D
101 - 138400Germany
BHA 45746144/05MPHTire size 560-14
BHA 46366144/15KPHTire size 560-14
BHA 46376144/13KPHTire size 155-14
BHA 46386144/14KPHTire size 165-14
138401 - 153877Canada
138401 - 332925Not USA, Sweden, Germany, orV8
BHA 47076144/20MPHSTD
BHA 47096144/21KPHSTD
BHA 48126144/23MPHO/D
BHA 48136144/24KPHO/D
138401 - 158230Not USA, Sweden, Germany, orV8
BHA 47076144/20MPHAuto
BHA 47096144/21KPHAuto
158231 - 328800Not USA, Sweden, Germany, orV8
BHA 48686144/28MPHAuto
BHA 48696144/29KPHAuto
332395 - 361000Market Unknown
BHA 52796144/20BSMPHSTD
BHA 52806144/21BSKPHSTD
BHA 52816144/23BSMPHO/D
BHA 52826144/24BSKPHO/D
360301 - 410350Market Unkown
BHA 53395230/13MPH
BHA 53405230/14KPH
187211 - 258000Sweden & Germany
BHA 49245227/20KPHSTD
BHA 49255227/22KPHO/D
BHA 49265227/24KPHAuto
258001 - 410000Sweden & Germany
BHA 50875231/08KPHO/D
BHA 51645231/95KPHO/D
138401 - 2580000USA, USA for Germany &Canada
37H 37665226/05MPHSTD
37H 37665226/03MPHSTD
37H 37665227/07MPHSTD
37H 37685226/08MPHO/D
37H 37785227/12MPHO/D
37H 41805227/16MPHAuto
258001 - 282419USA, USA for Germany &Canada
BHA 50845231/00MPHSTD
BHA 50865231/04MPHO/D
282420 - 410000USA, USA for Germany &Canada
BHA 51615230/065MPHSTD
BHA 51635230/085MPHO/D
BHA 52105230/11SMPHV8 (Except police)
Change point unknown, but
after car # 410000
AAU 30355234/00MPHRHD
AAU 3036Z 65465MPHRHD Police
AAU 30275373/00MPHLHD