Hi all!
First post, so my apologies if its in the wrong section or anything...
I recently acquired a Smiths mechanical rev counter from a Triumph Spitfire 1300, with a cable to spin the internal magnet rather than using electrical pulses to show revs.
Is there any way to put this to use on a Morris? As far as I am aware it would connect to the gearbox?...
Not sure about 'connecting to the gearbox - it might physically, but must be driven from the engine. How do you get any drive when sitting in gear and stationary and with the engine running?
Mechanical drives are often taken by a reduction gear driven from the camshaft, but I know not how this one was organised. I somehow think you may need some considerable modification.
Electronic rev counters have so many advantages - transducers, wiring can be circuitous, don't wear out, head can be fitted wherever you wish, easily regulated if inaccurate, etc.
Even most, or all, speedos are electronic these days. Nice to have these old rev counters but nowhere near as practical as their modern replacements, which have been around long before the minor era ended.
Thanks oliver90! I had my suspicions on how much modification it would need... I suppose getting an electronic example would really be the best option without doing a fair bit of work...
Thanks RobThomas! I think I'll try getting my hands on a Triumph Haynes manual to see whats what and get a better idea of the thing as well...
C39-PV2 extended drive dynamo from the Frogeye Sprite with mini gearbox to allow for the difference between dynamo pulley and crank pulley size.
Another option is to put a slot in the end of the camshaft and mount a 90-degree gear to drive the cable. All depends what ratio the Spitfire revcounter dial uses. 3:1 or 2:1 are common with the latter being ideal for running direct from the camshaft that rotates at 1/2 crank speed.
The early Sprite revcounter drive was taken through a small gearbox attached to the rear of the dynamo. I sold one recently.... for surprisingly good money. Wasn't aware the Spitfire ever had a mechanical drive revcounter, but if it did - I imagine it would be the same arrangement.
