...i presume my speedo will not be accurate if i don't have the correct tyre depth? How do i compensate for this? What size tyre do i require on 17" rims to keep my speedometer correct?

Thinking of getting some 17" wheels now as i'm ditching the Avon 'widow maker' ZZ1's before they put me in the ditch. If i'm going to have four new tyres, i may as well have 17" rims now as i was intending to change them soon anyway.

smurfy.

 

Assuming your car is a MY00 or earlier you need 215/40/17 (Goodyear, Bridgestone, Toyo, etc.) or 205/45/17 (Pirelli etc.)

Cheers,

E.

 

If it helps you the circumference of 205x50x16 Goodyears I have run are 1883mm on the rim and 215x40x17 Kumo were 1860mm. If my maths are right 1.22% difference so not enoughto bother about but be aware of it.
Note the 17s are shorter/smaller so the speedo will over read.
Different tyre manufacturers products will vary slightly as will the rolling circumferences during the life of the tyre.

Fitting wider profile will increase fuel consumption.

 

Thanks for the info.
Will fuel consumption be much worse with 17" wheels as opposed to 16" on my March 2000 Classic? Should i be aware of any other differences between 16" and 17"? I presume the ride will be alittle harder, but overall will the benefits outweigh the disadvantages?

smurfy.

 

I think going to 17s is a looks thing. In respect of handling the biggest factor will be the ability of the actual tyres selected as opposed to 16s v 17s.
I have specific experience of an increase of over 11% going from 205x50x16 to 215x40x17.