Right, lets break it down further.
Originally Posted by Randy99CL
I measured the sidewall height on my slightly squared Pilot road 4's 160/60's, unsure of mileage, looks like they could last another 1.5k. From the apex of the tread with a square, caliper, and my eye I measure the total height from bead as 90mm. The tires brand new spec is 96mm. 90mm is 93% of original. Does this mean the speedo would show 7% faster speed...
60mph x .07 = 4.2mph add difference 64.2/60 = 107% speedo readingA 150/70 brand new is 105mm tall that's 9% taller than a 160/60
60mph x .09 = 5.4mph subtract difference 54.6/60 = 91% of actual speedo reading
How many miles or milimeters till a 150/70 will read true speed? also speedos are not very accurate anyways