One thing you would have to consider but haven't is where is the drop center
of the wheel. All wheels, outside of some implement wheels, have a short
side and a deep side. Tires must be mounted on the "short" side of the
wheel. Next time you have a bare wheel, look at how one side drops off
quicker to the inside, that is the side that you mount a tire from.
Michael
(a former tire jockey, not due any respect)
----- Original Message -----
From: "Michael D. Porter" <mporter@zianet.com>
To: "Don Marshall" <marshall@nefcom.net>
Cc: "suhring" <suhring@lancnews.infi.net>; "Rob C Swift"
<RSwift@AVMTOnline.com>; "Triumph List" <triumphs@autox.team.net>
Sent: Friday, September 22, 2000 7:47 AM
Subject: Re: Tire Mounting
>
>
>
> Don Marshall wrote:
>
> > I've never had a problem getting tires mounted, but I've had two
occasions
> > where the installer has cut the bead on a tire going onto a TR6 wheel.
>
> This was not because of the below, but rather because the installer was
> careless.
>
> > Recently, someone explained that the TR6 wheels are "sided", meaning
that
> > the tires have to go on from one side only. Apparently, if the
installer
> > tries to put them on from the "big" side, the tire will bind and the
> > machine can cut the bead getting it back off. It may be that modern
wheels
> > don't have this and some younger installers aren't aware of it.
>
> With all due respect (very little necessary) to tire installers, the
> above is absolute horse hockey. Next time anyone has a bare rim to
> examine, measure the circumference and/or diameter of both sides of the
> rim, measure the angle of the bead-retaining flanges of the rim, and one
> will discover they are the same.
>
> The reason why this is so is very simple. If one flange diameter were
> smaller than the other, and the beads were able to be seated equally on
> each flange, the tire itself would be distorted after mounting and
> proper inflation, which would cause it to fail prematurely and would
> also cause tread wear problems. But, such a tire/rim combination can't
> be seated properly.
>
> Quite simply, _all_ tires have two sides, both of equal diameter and
> cross-sectional profile. An asymmetrical rim would create an improper
> fit of bead flange to tire bead on one side, because the diameter of the
> rim at the bead retention area and the diameter of the tire bead itself
> would be mismatched.
>
> Whoever told you this tale deserves a dopeslap.
>
> Cheers.
>
> --
>
> Michael D. Porter
> Roswell, NM
> [mailto: mporter@zianet.com]
>
> `70 GT6+ (being refurbished, slowly)
> `71 GT6 Mk. III (organ donor)
> `72 GT6 Mk. III (daily driver)
> `64 TR4 (awaiting intensive care)
> `80 TR7 (3.8 liter Buick-powered)
>
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