Re: [CR]Tire Direction --> ???

(Example: Production Builders:Teledyne)

Date: Mon, 31 Mar 2008 17:21:10 -0700
From: "mike scammon" <mike@scammoncycles.com>
To: "John Barry" <usazorro@yahoo.com>
Subject: Re: [CR]Tire Direction --> ???
In-Reply-To: <18995.45437.qm@web50212.mail.re2.yahoo.com>
References: <d51ac5a60803311447o69cc6f4bj468f155ce2f14fec@mail.gmail.com>
cc: classicrendezvous@bikelist.org

On Mon, Mar 31, 2008 at 5:00 PM, John Barry <usazorro@yahoo.com> wrote:
> Sounds like another shot-from-the-hip Jobst theory.


>
> Anyone who has driven on good tires on a wet road, and
> then driven on bald ones on a wet road and not noticed
> a difference, would have to be either very distracted,
> or borderline comatose.

Sounds like you're comparing bicycle tires to car tires? Car tires are affected differently due to their rectangular footprint, which reduces their ability to purge water. I have raced for years in wet and dry (not while comatose or distracted). *Any* difference in cornering traction in wet weather (where the tire is the cause) is from the casing deflection or rider skill etc... and *not* from the fact that it was treadless.
>
>
> Hydroplaning is a very real phenomenon,

t's not really a phenomenon. It's more basic physics and again, your comparing a car vs a bicycle. The round shape of the bicycle tire prevents hydro planing much better than a car would. that should be pretty simple to understand.

and to suggest that tread pattern could not have some bearing on how
> severely hydroplaning affected a tire just doesn't have their facts
> straight.

It does have bearing. Just the kind you don't want from a road tire. Please tell me how having treaded road tires helps you fend off hydro-planing? Or aids in cornering? This argument is old and has been disproven many times over.


> I'll leave the posting of
> citations on the topic to the engineers here.
>
> John Barry
> Mechanicsburg (where bald tires wouldn't be a good
> idea tonight), PA, USA
>
>
>
> >
> > Anyway, here's Jobst on the subject (found on line).
> >
> > *snip from Jobst*
> >
> > * Tread patterns have no effect on surfaces in which
> > they leave no
> > impression. That is to say, if the road is harder
> > than the tire, a tread
> > pattern does not improve traction. That smooth tires
> > have better dry
> > traction is probably accepted by most bicyclists,
> > but wet pavement still
> > appears to raise doubts even though motorcycles have
> > shown that tread
> > patterns do not improve wet traction.*
> >
> > */snip Jobst*
>
>
>
>
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>

--
Mike Scammon
Menlo Park, Ca.