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‘Good luck with your project’... Enjoy your classic motoring...
Fixed price repairs are based on the assumption that unit/s received
are ‘original & complete’... a surcharge may be applied to cover
missing parts etc... If in doubt send in the unit for inspection
Fixed price repairs are based on the assumption that unit/s received
are ‘original & complete’... a surcharge may be applied to cover
missing parts etc... If in doubt send in the unit for inspection
If you found this web site via a ‘search engine’ please
check that you are looking @ the latest version... click here
Jaguar XK 120 ( 1948 / 54 )
1788.1 M
Payment options
JDO Instruments
Classic Car Instrument Repairs ( Est 1963 )
Fixed price repairs for most British & European Classic Car Instruments
48hr service available... Why pay more & wait longer ! No UK vat
Tele: (UK) 01535 672125 Mobile / SMS: 07831 886545
Please check the FAQ’s page BEFORE ringing / emailing... thank you
Classic Car Instrument Repairs ( Est 1963 )
Fixed price repairs for most British & European Classic Car Instruments
48hr service available... Why pay more & wait longer ! No UK vat
Tele: (UK) 01535 672125 Mobile / SMS: 07831 886545
Please check the FAQ’s page BEFORE ringing / emailing... thank you
Information required to Check / Re- Calibrate a Speedo
print off a copy & enclose with your order...
*Jack up just 1 Driven wheel Measure the Circumference of the fitted tyre in inches = _______ cms = _______
Remove the Speedo...make up a cardboard pointer or similar & fix it to the end of the exposed inner speedo cable
Put a chalk mark etc on the edge of the tyre & the ground ...
Now turn the ‘Jacked up’ wheel 20 turns forward ( out of gear )
& count the number of turns the speedo cable makes = ___________ to the nearest 1/8 ( eighth ) of a turn
* The above assumes a Normal diff unit ... if the car is fitted with a Limited slip diff ( LSD)...
Jack up Both driven wheels & turn one wheel 10 turns forward ( out of gear )
take up the ‘LSD’ slack first ie. until the OTHER wheel starts to turn ( approx ½ turn ) this will give the same result
Please state the FULL tyre size _____________________ & type eg. Radial / Cross-ply ( delete one )
However if your car is on the road & running ask a friend etc to pace you in another car * with a speedo known
to be ok... ie. set the Trip on both cars to zero ... Travel approximately 10 miles / 16 Km & advise both readings
eg. True distance = _______ Your cars indicated distance = ________ to the nearest 1/10 ( tenth ) of a mile / Km
Or use a ‘reliable’ Sat-Nav
print off a copy & enclose with your order...
*Jack up just 1 Driven wheel Measure the Circumference of the fitted tyre in inches = _______ cms = _______
Remove the Speedo...make up a cardboard pointer or similar & fix it to the end of the exposed inner speedo cable
Put a chalk mark etc on the edge of the tyre & the ground ...
Now turn the ‘Jacked up’ wheel 20 turns forward ( out of gear )
& count the number of turns the speedo cable makes = ___________ to the nearest 1/8 ( eighth ) of a turn
* The above assumes a Normal diff unit ... if the car is fitted with a Limited slip diff ( LSD)...
Jack up Both driven wheels & turn one wheel 10 turns forward ( out of gear )
take up the ‘LSD’ slack first ie. until the OTHER wheel starts to turn ( approx ½ turn ) this will give the same result
Please state the FULL tyre size _____________________ & type eg. Radial / Cross-
However if your car is on the road & running ask a friend etc to pace you in another car * with a speedo known
to be ok... ie. set the Trip on both cars to zero ... Travel approximately 10 miles / 16 Km & advise both readings
eg. True distance = _______ Your cars indicated distance = ________ to the nearest 1/10 ( tenth ) of a mile / Km
Or use a ‘reliable’ Sat-
Calculation page
Re-Calibration surcharge