Speedo calibration questions.
Before I pull the needle on the old speedo, a 1.5 V battery brought it to 40 MPH, and that’s where I set it on the new speedo.
@scotts90ranger said when he did it, it was 42. I figure I’ll start there with a brandy new quality battery.
1st question: is anybody aware of a calibration chart? Charge that would show what the different reading should be at different voltages? I actually have a desk top DC voltage generator, so calibration chart with softball problems.
Now, when the school radar camera says I’m going 41 miles an hour, the speedo reads 34 miles an hour, so reads 7 mph low.
2nd question: would that mean I am reading seven mph low at any speed? Or am I reading 20% low at any speed? Question is, is the needle rise linear or proportional?
Assuming it reads 7 mph low at any speed: I’m thinking I’ll remove it, attach a brandy new quality battery and wherever it reads, simply pull the needle and set it 7 MPH higher, and reinstall. Yes/no?
3rd question: one Internet video (the guy didn’t strike me as an expert or as a rocket scientist in general) simply presented that if you pull the needle, and, with no power, you set it at zero at the restraining pin on the bottom, it knows where to go all by itself. For clarity, it was not a matter of letting it fade counterclockwise until it hits the pin, but rather actually placing it at the pin, so there is no downward pressure, no matter how slight. Yes/no?
As always, any at all input is greatly appreciated.
I won’t be doing it for a few hours.
@Curious Hound understands that it will take me a couple hours to come to grips with the concept, and build the strength, to actually go to a retail store and buy a brand new battery that’s not on sale. It goes against every fiber in my being.
