My own two cents:

"Optimal" tire width to rim width generalized for the "average" tire
TIRE            RIM
185mm        5.0"-5.5"
195mm        5.5"-6.0"
205mm        6.0"-6.5"
215mm        6.5"-7.0"
225mm        7.0"-7.5"

Note: running 1/2" smaller rim than the above table will work, but is less
than optimal due to the resultant sidewall curvature. Running 1" smaller rim
than the above table is darn right dangerous.

Caveat to the above rule:
"Some" tires are designed outside of the generalized rules above. Check with
the tire specifications for each different manufacturer and err on the plus
side of the rim width. Example: BFG says 27x8.5x14 TAs will work on rims
from 6.0" to 7.0". You are better off with 6.5" to 7.0" than using a 6.0"
rim on such a wheel.

Cheers, MJS

Joachim Beek wrote:

> Howdy Volks,
> with all this talk about steel and alloy rims and tire sizes, I got to
> wondering what is the relationship between rim width and what width tire
> that rim will take?
> Joachim
> 90 GL
> 78 Scirocco
> ---
> Spoonerism: Hap shittens.

--
Michael J. Sullivan
Director of Catalog Design
Open Market Inc.
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   work: http://www.openmarket.com
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