Tire Question

[dolce vita]

Sorry for the rookie post--

My D-4D came with the P175/65/R14 Bridgestone tires. Need new ones soon. Can I upgrade to the P185/65/R14 tires without any problems, on the same rims? I looked on the US Michelin site (though I live in Italy) and it seems like they suggest I can on the same rims. The standard Bridgestones seem good but a relative has Michelins on a Golf I've rather liked the handling of.

Thanks

dave

[Ryan1985]

Yes they should fit no problem I would think but don't take my word 4 it! Do u know how wide ur wheels are?

[dolce vita]

Isn't that what the P175 part of the number is about? Like 175mm? Is that what you mean?

[yvvan]

Hi Dave,

You could use 185/65-14 tyres, the speedometer will read about 2,2% slow.

You could also use 185/60-14 tyres, the speedometer will read about 0,9% fast.

If it's Michelin Pilot Exalto's you're after, which I guess since you mention the good handling, the only 14" size they now come in are 185/60 R14 82V.

Cheers, Yves.

[dolce vita]

Thanks Yvvan,

Can I ask how you figured those numbers? I'm also curious why tires with the same sizes (other than width) would change the reading of the speedometer...

thanks

dave

[yvvan]

Hi Dave,

I use a program on my computer, but there are several tire size calculators on the net, try a google.

The speed reading (on the same rim diameter) is not affected by the width of a tyre (the first bit of the name) but by the height (the second bit of the name), it's expressed in a percentage of the width, eg 185/65, here the height of the tyre section is 65% of 185 mm or 125.25 mm, for a 185/60 tire it's 60% of 185 mm or 111 mm.

Cheers, Yves.