Re: do bigger tyres = slower or faster than actual speedo readings?
Mon, 21 March 2005 20:07
You are right, the speedo is showing less than you are actually travelling - I believe by just over 6%. Essentially, the new tyres have a smaller circumference, so every turn of the 60 profile wheel, you travel about 1900mm, where on the 50 profile you travel about 1800mm.
The speedo is calibrated to believe it is travelling 1800mm per revolution, where you are now travelling 1900mm.