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Tyre question
big_wasa - 5/7/09 at 12:52 PM

The tyres on my rims are 185 x 70 x 13.

when they are done I want Toyo r888's

These come in 185 x 60 x 13's.

Whats the differance in radius as I want to make the wing brakets up and dont want huge gaps when it comes to changing tyres ?

I dont want to change them yet as they are A) New and B) Free-ish proper locost like

cheers

[Edited on 5/7/09 by big_wasa]

eccsmk - 5/7/09 at 12:55 PM

-37mm
calculator

[Edited on 5/7/09 by eccsmk]

big_wasa - 5/7/09 at 12:59 PM

That was quick and just what I wanted

On the down side thats huge thats 18.5mm more gap between arch and tyre

eccsmk - 5/7/09 at 01:03 PM

its the distance in the circumference not in height mate

big_wasa - 5/7/09 at 01:05 PM

ok I will do some sums

edit

It says Diameter not circumference ?

[Edited on 5/7/09 by big_wasa]

eccsmk - 5/7/09 at 01:13 PM

actually it'll be the length of the rolling radius
mark the tyre where it meets the floor
roll it forward until mark is at the bottom measure how far it rolled.

PAUL FISHER - 5/7/09 at 01:17 PM

Best option might be to go up to a 205 60 13 all round,or I would at least put 205's on the rear,and the 185's on the front.

speedyxjs - 5/7/09 at 01:26 PM

quote:
Originally posted by big_wasa
I have tyres on my rims.


Well thats a bold move

big_wasa - 5/7/09 at 01:29 PM

quote:
Originally posted by speedyxjs
quote:
Originally posted by big_wasa
I have tyres on my rims.


Well thats a bold move


Well they have been in the bedroom for the last four years

SteveWalker - 5/7/09 at 02:24 PM

quote:
Originally posted by big_wasa
The tyres on my rims are 185 x 70 x 13.

when they are done I want Toyo r888's

These come in 185 x 60 x 13's.

Whats the differance in radius as I want to make the wing brakets up and dont want huge gaps when it comes to changing tyres ?


The 70 or 60 figure is the tyre wall height as a percentage of the width in mm, so a change from 70 to 60 is a reduction from 70% to 60% of 185mm, giving 18.5 mm, as your wheel size remains 13", you are reducing the radius of the tyre by that 18.5mm (tyres with no second figure are by default 80%).

gingerprince - 5/7/09 at 03:03 PM

Don't forget about the fact (or rumour?) that R888's and other road legal track tyres are due to become illegal in the next few years. So if you're not planning on buying for a while, just be sure you've still got time to destroy them before the law changes!