Re: Nomenclature for tyres
 January 06, 2013 03:57AM James Jessiman Memorial Award Recipient LDraw Part Author/Reviewer Registered: 4 years agoPosts: 428
Which "width" is used to measure tyres?
Quote
Chris Dee
The "width" should be the maximum outer width.
Of what? The tyre or the rim?

The rim to be used here is 22969.dat, "Wheel 56 x 46 Technic Racing".
Maximum width: 116ldu x 0.4 = 46.4mm
Maximum visible diameter: 2 x 68ldu x 0.4 = 54.4mm
A new name for this rim could be: "Wheel Rim 46 x 54 Technic Racing"

The dimensions of this tyre, 32998 is:
Maximum outer diameter: 2 x 131ldu = 104.8mm
Profile height is: 131 - 68 = 63ldu x 0.4 = 25.2mm
Maximum width of rim (same as above) = 46.4mm
Maximum width of tyre: 76ldu x 2 x 0.4 = 60.8mm

A new name for this tyre would be...
if we use "max rim width": "Tyre 46.6/ 60 x 54 Off Road"
or, if we use "max tyre width": "Tyre 60.8/ 50 x 54 Off Road"

My opinion is like this:
Wheel:
(width_(mm) x rim_diameter_(mm) [optional qualifier])
"width" means "maximum rim width" in mm (without decimals)
"diameter" should be without decimals, unless it is below 10mm, then one decimal

Tyre:
(width_(mm) / profile_as_%age_of_width x rim_diameter_(mm) [optional qualifier])
"width" means "maximum tyre width" in mm (with one decimal)
"profile" should be rounded up to the nearest ten
"diameter" should be without decimals

Should both tyre and wheel use the same definition of "width", or should they have different definitions?
SubjectAuthorViewsPosted
Max Martin Richter977December 24, 2012 06:20AM
Philippe Hurbain320December 24, 2012 06:58AM
Chris Dee338December 24, 2012 08:25AM
Magnus Forsberg387January 06, 2013 03:57AM
Chris Dee282January 06, 2013 01:49PM
Magnus Forsberg395January 07, 2013 10:22AM
Magnus Forsberg332December 24, 2012 03:21PM

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