I have a escort mkii 4 speed gearbox with mechanical drive going to a smiths speedo out of a dolomite. Having clocked it, it would appear to be registering only half the speed. Does anyone know if you can get a new gear drive for the gearbox or do I need a new speedo?

I think speedy cables may be able to recalibrate them...

Second Speedy Cables. They will need more info but if you ring them they will tell you everything you need to Know. Cost wasn't too bad last time I had a speedo done.

I can recommend this guy.
http://www.jdo1.com/

Barry

If you cannot be separated from your speedo, then there are at least 2 companies that can recalibrate it for you.

this process involves changing the gears for the odometer and re-magentising the speed indicator., the latter is something that you cannot do at homw without specaiolaist equipment.

the cost will be around £ 60.

if ou in future decide to put in a different gearbox or diff or tyre size, it may well be out.

I'd recommend you try to find a speedo from a donor that matches the above parameters - loads on aebay of a tenner.

The alternative, and I went through this dilemena, is to fit an electronic speedo.

Cost will be about 3x recalibration since you also need a sender - I made my own so it was not so ££££

this gives you total flexibility.

cheapest option is a bicycle speedo, £ 5., but needs illumination.