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tyre size
needforspeed - 1/11/11 at 09:55 PM

whats the best size tyres for 7x13 and 8.5x13s? have sizes for slicks/wets but dont know how to convert them to conventional sizeing!


britishtrident - 1/11/11 at 10:22 PM

Unless things have changed radially since my racing days.
Normally racing tyre tread widths are 0.5" to 1.5" narrower than the rim width ----


for example 9.2-22 x 13 x-ply or 230/550 R13 radial would be used on a 10" wide rim.

9.2" or 230mm is the tread width
22" or 550mm is the nominal (outer) rolling diameter of the tyre carcass

[Edited on 1/11/11 by britishtrident]


paublo999 - 1/11/11 at 10:33 PM

I would agree. I am running 10" rears now for a 9.2 tyre. 9.2" Avon A15 hillclimb soft's are great for off the line grip as I am now down to 2.00 for 64ft


phelpsa - 1/11/11 at 10:35 PM

They sound prime for 7.2 fronts and 8.2 rears. Slightly narrow wheels but should work fine.

EDIT: or are you saying that you're after road tyres but know slick sizes that fit?

[Edited on 1-11-11 by phelpsa]


needforspeed - 1/11/11 at 10:42 PM

quote:
Originally posted by phelpsa
They sound prime for 7.2 fronts and 8.2 rears. Slightly narrow wheels but should work fine.

EDIT: or are you saying that you're after road tyres but know slick sizes that fit?

[Edited on 1-11-11 by phelpsa]
correct


phelpsa - 1/11/11 at 10:54 PM

Replied to your U2U, but just to stick it out in the open, I would recommend a call to BMTR. They can supply both hillclimb compound slicks and Avon ZZRs for the road, and advise on sizes and a geometry compromise that might work for both.