speedo sensor compability
 

I have a 1978 915 box missing the speedo sensor and my buddy happens to have one from an 85 box. It would be nice to know if they are compatable before he sends it to me.

This is a custom build and the wiring is not an issue. As long as it fits the blockout in the box and pulses X times per wheel revolution I can make it work.
Presumably both are reed switches.

Will the 85 physically fit the 78 box, or is there more to it

HI Robert
the sensor will fit, for what you require, do you have the small retainer clip to hold in the sensor.

regards mike