Hi, Yes I have a question if someone could help with an ansewer. I Have a 69 V.W. with a VDO Speedometer that reads faster than the car is going, I have cheked the square hole in the hub and the cable seems to be o.k.my question is how do I adjust the speedo to get the right reading. Note I have already had it calibrated, I dont know what else to do. Faced with buying another but fear I will run into same problem. HELP!
They ~typically read ~3-5% high from the factory (faster than the car is going---this is fully intentional, 2012 models as well, all makes )
You say you had it calibrated--- By whom? Make them do it properly.
A speedometer shop has the gear to TEST this and can fixs, but it might be less expensive to simply source another stock speedo.
Are you running stock diameter tires? The speedo shop needs this info.
All "traditional" speedometers are based on one of Nicola Teslas many discoveries/inventions, Once you understand how they work, what to adjust becomes obvious:http://en.wikipedia.org/wiki/Speedometer#Eddy_current