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I have a technical question: how does the R6's computer calculate the speed at which you are traveling and how many miles you've traveled? Does it calculate miles traveled by counting rotations of the drive tire (like in a car)? And does it do the same for calculating speed, or does it measure something else like output shaft RPMs or the RPMs of the sprockets based literally on the # of teeth, i.e. diameter/circumference of the sprockets?? (Sounds like it could be the winning explanation)... Let me know about both odometer and speedometer reading calculation methods...

My goal here is to identify the legitimate scientific explanation of what actually causes the speedometer error when you do the -1 +2 etc. gear change... I would think that theoretically a change in gearing would only change the rate of acceleration, not cause an inaccurate speedometer reading, but I guess that depends where/how the speed is calculated! So is the speed actually calculated with a formula involving the circumference/diameter of the sprockets i.e. number of teeth or is it done some other way??

As a side note, I know that a change in overall tire and/or wheel circumference/diameter would throw off your speedo/odo's accuracy ASSUMING that the vehicle's speed/distance traveled is calculated in a formula based on the circumference and RPMs of the drive tire, but that's not really an issue with bikes...

I just want to know how the bike's computer calculates the speed to confirm why the speedo is inaccurate!!! And yes, I'm aware that the speedo is intentionally calibrated high from the factory so leave that part out of your answers:) ... GOOD EDUCATED ANSWERS ONLY PLEASE!!! Please correct me if anything I've said is wrong or let me know if I'm missing anything, cause I'm not an expert... Thanks!:hattip
 

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the computer reads your speed through the transmission. so the comp. knows when the shaft(or somthing in the tranny but im gunna say a shaft) in the tranny is rotating however fast your moving however fast.

in that "equation" it uses to convert the speed of the shaft to the speed of the bike, it leaves the sprockets and tire as constants. so, if these things are changed, the computer has no way of telling and therefore cant correct its "equation".(this is where a speedo healer comes in). so since you have -1 +2 the shaft in the tranny will have be spinning faster to keep you at the same speed you would normaly be at with stock sprockets (which is the point of the sprocket change, to be at a higher rpm at all times to give more torque than you would normally have at the same speed)

remember is doesnt know that they were changed so the bike thinks your going faster but your not, your revving higher at the same speed. same goes for a larger tire on the back. a larger diameter tire goes further with one rotation than a small tire. so the bike will be going further/faster at 60mph(or any mph) than a small tire at 60mph. and again the tire diameter is a constant in the "equation" that was changed and the computer doesnt know it, so you get a false reading on the speedo.

and everything here relates to distance traveled. because of course, d=v*t (distance=velocity multiplied by time). so there is a direct relation between distance and speed. your bike thinks its going faster so it thinks its going further also.



feel free to correct me if i am wrong. hope this helps :thumbup
 
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