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Only in theory. Modern bikes don't have speedo cables, it's an electronic pulse sensor.

If it was still a cable, you'd need to do roughly a thousand revolutions of the cable to get the odometer to register 1 mile. If your drill does 1,000 rpm, and assuming the cable inner doesn't start to melt the sheathing on the outer through friction, you'll still need to keep your drill spinning for 30 days continuously. Or drills, since you'll burn out several along the way. The cost of the new power tools, several new speedo cables, the month of your life 24x7 to actually do the winding and the electricity to run it all will dwarf the change in value you get from winding 4,000 miles off the mileage of your bike.

For the pulse sensor, if you could devise a gizmo that generated pulses to plug in to it, you could roll the mileage around that way, but only at '186mph' - they won't register any more than that I believe (I assume the odometers won't roll up any faster either). However, the digital odometers sometimes don't roll over until they hit a million miles, and that would mean leaving your electronic pulse gizmo plugged in and running for about 8 months...

There are specialist firms used by second hand car trade (you are suprised?) who will 'correct' (yeah, right) mileages on those LCD digital mileometers. In the UK they can often be found hanging around outside car auctions offering to 'correct' the mileage of cars that traders have just bought...

See http://thedashdoctor.moonfruit.com/ for a UK example. You need to find something similar in the US...
 

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Did you ever find out why? Had you changed the windscreen for a double bubble or similar? A guy in the UK found his clocks were melting but worked out why. The aftermarket screen he had fitted was acting like a magnifying glass and focusing the rays of the sun on the clocks at certain times of the day and melting the dash...
 

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Yes, there usually is some gearing - I've no idea whether it's usually a reduction or not. I was just ignoring the possibility to simplifying the calculation for illustration purposes.



It's worth pointing out that even if it is reduced a lot,, you can't just run the speedo at a thousand miles an hour to rack up the odometer miles more quickly, because the old fashioned speedometer is likely to explode messily under the strain.
 

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I was thinking that the rotating components of the average built-down-to-a-price motorcycle speedo are unlikely to have been dynamically balanced for high-RPM rotation nor equipped with a suitable bearing if they are designed to rotate slowly, and just the vibration of running continuously for 4 days and nights at 1000mph may cause things to self destruct, never mind the heat. I'm also thinking that if you run the speedo drive 8 times faster than it was ever designed to run, you are generating roughly 8 times the magnetic field and thus 8 times the current in the field coils and 8 times the turning moment on the pointer. Since the only thing stopping the pointer from spinning like a desk fan and winding the hair-spring up to destruction is usually a little end stop right down near the end of that long, thin, lightweight metal or plastic pointer, and the only thing stopping the central shaft spinning and leaving the pointer to drop off if that stop holds is usually a little detent or flat on the end of that tiny shaft, I wouldn't want to bet real money that the speedo would ever play the piano again after subjecting it to the 1000mph rewind experience.



The only way to know for sure would be for a MOron with time on his or her hands and a spare speedometer to rig something up and do an experiment for us, then write up the results.



In fact, that's just the kind of quality motorcuycle-related article I pay my subscription for. Get right on it, MO!
 
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