Speedometer calibration
Posted: Sun Jul 25, 2021 10:56 pm
Thirty years ago I recalibrated my speedo, I can't recall why, and it has indicated about 10% fast ever since and I know now that I put the pointer on too far behind the stop. Having decided to correct it, at last, I have no idea what I adjusted to change the gap between magnets and drag disc (which drives the pointer) and assume I need to increase it. I have a memory of adjusting a lock nut which controlled end float but I don't recognise any of it.
Also, in the last few years, the needle has been reluctant to move off zero in cold weather. This picture shows where the spindle comes out at the top (between the two 5s) and I've sparingly touched sewing machine oil on it where it emerges.
What does the little brass screw do (just this side of the spindle)? It seems to pull up on the similar brass bar below it, but I can't see why that's there unless it supports the spindle. I've tightened it 1/8 of a turn hoping to stop the cold weather jam and perhaps reduce the over-reading.
Any ideas gratefully received, thanks.
Also, in the last few years, the needle has been reluctant to move off zero in cold weather. This picture shows where the spindle comes out at the top (between the two 5s) and I've sparingly touched sewing machine oil on it where it emerges.
What does the little brass screw do (just this side of the spindle)? It seems to pull up on the similar brass bar below it, but I can't see why that's there unless it supports the spindle. I've tightened it 1/8 of a turn hoping to stop the cold weather jam and perhaps reduce the over-reading.
Any ideas gratefully received, thanks.