>Jay, after you give them the info from the speedo, what
>do they do, and is the speedo accurate over the entire
>range, and is so to what plus or minus mph?
I just spoke to Mo-Ma. She told me that if she used to 1040 gauge I have
(from a SIV Automatic), she could use a 41 tooth gear and get pretty close,
but not exact. I may have to go to an external converter to get closer to
exact.
The speedo is a completely different issue. It is not fixed by gears. I
know I am going to get corrected on this one. But, this is as close as I
know - and as always, I'm willing to be corrected. Attached to the head of
the cable is a flat disk with a magnet. This disc fits in a flat metal
dish to which the needle is attached. There is nothing connecting the dish
to the disk. When the magnet on the cable spins, it creates a magnetic
force that lifts/turns the dish and the needle. As the dish spins faster,
the force increases and turns the disc further. In order to calibrate the
speedo then, they don't change gears, but change the amount of magnetism in
the dish or the plate or both. There is also, I think, and adjustment to
the resistance against the plate.
That being said, I believe there is an inherent inaccuracy in the speedo
needle such that it cannot be 100% accurate at all speeds. You need to
pick what range you want to be most accurate, and live with the other
zones. My driving takes me through a very long 45 mph speed trap. But,
then 65 is always a concern. I don't know how wide the band is of
accuracy. I'll probably shoot for right in the middle of those two.
Jay
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