How do i calculate my tyre size??

Ive just bought some 235/70/16 tyres and wanted to know the diameter of them, just to know how tall they stand compared to my current tyres.

now i thaught it was worked out as follows

235*.70 + 16 (in mm) ?? = 574.4mm

but when i enter it into a tyre calculator i get the following

759mm

can somebody please help with my confusion!!

Thanks

Ollie

Try this link, might be of some help to you?

Tire code - Wikipedia, the free encyclopedia

Thanks for that, but i still dont understand when i calculate the diameter it is different to the results from online tyre calculators??

Ollie

The 235 x 0.7 is the height of the sidewall (ie from the edge of the rim to the outside of the tread). There's 2 times that, plus the diameter of the rim, in the overall diameter of the tyre.
235mm is 9.25"

9.25 x 0.7 = 6.5" so the overall diameter is (6.5" x 2) + 16" = 29"

Ahh i get it thanks for that, wasnt timsing the 235 x 0.7 bit by 2!

use a tape mesure!
it's loads easier:mooning:

nickh75 said:

use a tape mesure!
it's loads easier:mooning:

Click to expand...

Lol would have done, just im at uni in notts and my 90 is back in somerset. so unless youve got an extra long one it might be a bit far :ballchain:

Ollie

olmasters said:

Lol would have done, just im at uni in notts and my 90 is back in somerset. so unless youve got an extra long one it might be a bit far :ballchain:

Ollie

Click to expand...

ferk me hope your not doing a maths degree:doh:

Dont be silly! :bounce: