Weight of Wheels
#21
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Sorry for the delay. It took me a while to find out the tire size on the now-gone 17 ACS wheels.
Anyway, on the original BMW 16in, tire size: 225/55R-16
On the 17in ACS, tire size: 255/40R-17
Anyway, on the original BMW 16in, tire size: 225/55R-16
On the 17in ACS, tire size: 255/40R-17
#22
Rolling circumferece of the 17" wheels is 5.1cm shorter ie 2.5% difference so this shouldn't explain the big difference, I think the profile was 1 step too small on the 17's ......should have been 45 profile tyres
DD
Apologies for the maths!
DD
Apologies for the maths!
#24
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My Ride: G30 M550i
Model Year: 2018
You can see all the calculations for yourself using the following calculators:
This one gives a clear explanation of speedometer error:
Speedometer error calculator
This one (using javascript) gives a whole bunch of information:
Javascript tire size calculator
It seems that the error was closer to 2.8% and not 2.5%.
Have fun!
This one gives a clear explanation of speedometer error:
Speedometer error calculator
This one (using javascript) gives a whole bunch of information:
Javascript tire size calculator
It seems that the error was closer to 2.8% and not 2.5%.
Have fun!
#25
Ah well rudy, I worked it out mentally so to be 0.3% out restores my faith in my grey matter!
Still doesn't account for the big mileage difference....bit of a mystery there!
I see you're nearly at 400 posts yourself....You'll overtake me bigtime soon!
DD
Still doesn't account for the big mileage difference....bit of a mystery there!
I see you're nearly at 400 posts yourself....You'll overtake me bigtime soon!
DD
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