bigjohnsd
2021 BMW R1250GSA
GPS read 80 bike speedo read 82 with cruise set on a dead straight Wyoming byway.
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2013 FJR Digital Speedometer Accuracy
- Thread starter Wine Guy
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Just Krusen
Well-known member
RadioHowie
I Miss Beemerdons!
Sorry...had to correct it for ya. Here in Central Florida, the altitude completely changes the equation.
Just Krusen
Well-known member
I know. I get nose bleeds when I go that far north.
Bustanut joker
Well-known member
??????????????
yer kidding .................
Right?
No wonder some of us want to commit suicide.
For fuks sakes!
yer kidding .................
Right?
No wonder some of us want to commit suicide.
For fuks sakes!
Twigg
Just an old, bald man!
Speaking as someone from the land where not only is the Queen on the currency and stamps, but she actually lives there too ...
The construction and use regs. for vehicles state that speedometers have to be accurate to within 10%. That's a pretty gross amount of allowable inaccuracy, but it does mean that with the advent of GPS, the speed limits all went up by a de-facto 10% because they can't bring a prosecution if your vehicle complies with the law.
The speedometers in police cars are calibrated, probably daily for the traffic cops, and those calibration records are available to the defence if one is raised in court. Missing calibration certs gets the case thrown out.
That said, 10% is a woeful figure, and we have the right to expect much better. The last time my odometer was checked for a rally it was under 1%, and that on a 30 year old bike.
I'm pretty sure Yamaha, despite the usual bean-counters, do know how to make a decent speedometer. I would speculate that they err on the side of caution when they are calibrated, and try to ensure that they never read low even with the tires and pressures at the outside of the permitted envelope. Especially here in the US, where some cops will write tickets for 1 or 2 mph over. So I would generally expect speedos to be a bit optimistic, but surprised if that were much more than 3 or 4% ... and usually expect it to be better, especially in the 30 to 70 mph range.
The construction and use regs. for vehicles state that speedometers have to be accurate to within 10%. That's a pretty gross amount of allowable inaccuracy, but it does mean that with the advent of GPS, the speed limits all went up by a de-facto 10% because they can't bring a prosecution if your vehicle complies with the law.
The speedometers in police cars are calibrated, probably daily for the traffic cops, and those calibration records are available to the defence if one is raised in court. Missing calibration certs gets the case thrown out.
That said, 10% is a woeful figure, and we have the right to expect much better. The last time my odometer was checked for a rally it was under 1%, and that on a 30 year old bike.
I'm pretty sure Yamaha, despite the usual bean-counters, do know how to make a decent speedometer. I would speculate that they err on the side of caution when they are calibrated, and try to ensure that they never read low even with the tires and pressures at the outside of the permitted envelope. Especially here in the US, where some cops will write tickets for 1 or 2 mph over. So I would generally expect speedos to be a bit optimistic, but surprised if that were much more than 3 or 4% ... and usually expect it to be better, especially in the 30 to 70 mph range.
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