Rev Counter

[richard btype]

Whilst on the subject of gauges, my rev counter works but is less than smooth or should I say lacks immediacy to move up or down is this more likely to be the generator or an instrument that needs a clean?

[Heuer]

Most likely the generator. It uses magnets to generate an electrical pulse (1v/100rpm - the tach is just a big voltmeter)) but over time they weaken and the voltage drops so they under read. Easiest way to test this is to attach a digital rev counter (you get them on some timing lights etc) and compare readings. They can be as much as 25% under! The repro generators are not good and are prone to early failure by disintegrating.

If the generator is OK then it could be the needle spindle that needs cleaning. Fairly easy to do by dismantling the rev counter case and using aerosol switch cleaner on the bearings. Do not apply oil afterwards. Alternatively send it to Richfield Speedograph or similar for service.

[richard btype]

David

With the tacho removed the easiest option to start with was cleaning the bearing, previously the needle would not return fully to start position - after cleaning it does this without hesitation.

Thank you once again..

Richard