Tyre Q

[planetdave]

If I change my tyres for some that are an inch taller how will it effect performance/handling/economy. I think ride will improve,turn in suffer but grip improve (longer contact patch). How much will the speedo go out?

[kevinday]

On all counts you will lose performance. To fit higher profile tyres withe no increase in width will raise the centre of gravity, thus reducing handling, the performance will reduce as the gearing is no longer at the optimum as will fuel consumption. The tyre contact patch would be unchanged. You could increase the contact patch length by loweing the tyre pressure but this also has adverse side effects.

The normal route is to increase the width and reduce the profile to maintain the same rolling circumference. If you post the wheel and tyre sizes you have I could recommend some sizes that IMO (I am not a tyre engineer) would work on your existing rims.