Re: Run Flat tires

[Werehatrack]

On Mon, 13 Dec 2004 12:39:48 -0500, Lee Lindquist <[email protected]> wrote:

>
>I'd like to set up a bike for commuting.
>
>Is there such a thing as run flat tires for bicycles?

Not exactly, "Airless" tires and tire conversions exist, but they are
widely disparaged as being too stiff, too heavy, often too expensive,
and usually too difficult to install.

>Alternatively, is there something I can fill the tires with
>that will turn into foam, or something, and achieve the
>same effect?

Technically, yes, a bike tire could be foam-filled. The equipment to
do this is not found in the bike market, however; visit an industrial
lift truck[1] tire specialist to see if it's possible in your area.
bear in mind that you will end up riding tires that are literally
about as hard as rocks; if you run over a cigarette butt, you'll be
able to tell if it was plain or filtered. As an alternative, I would
point you in the direction of the recent (and numerous) discussions
here over the merits of Slime, thorn-resistant tubes, and tire liners.
Each of those offer some protection against flats, and even if used
together, all three at the same time would still not make the ride as
harsh as an airless or foam-filled tire.



[1] "Industrial lift truck" is the fancy, five-dollar mouthful of
words used for what most folks call "forklifts". You might find
either classification in your local Yellow Pages.



--
Typoes are a feature, not a bug.
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Words processed in a facility that contains nuts.

 

[[email protected]]

>>>>
Not exactly, "Airless" tires and tire conversions exist, but they are
widely disparaged as being too stiff, too heavy, often too expensive,
and usually too difficult to install.
<<<<

Unfortunately this _is_ what a lot of people say but the truth is that
most people _only_ say it _because_ they have read it in news groups
like this. In truth, most people do not have first hand knowledge of
Airless tires.

I, however, do and have found them to be super. When I'm riding to
work in the dark, in the rain, I want to be 100% sure that I don't get
a flat.

The fact that they weigh more and have about 1% more rolling
resistance, is of absolutely no consequence to me. I just want to get
to where I'm going and arrive on time.
Lewis.

***************************

 

[Terry Morse]

[email protected] wrote:

> The fact that they weigh more and have about 1% more rolling
> resistance, is of absolutely no consequence to me.

You dropped off a couple of zeros above. Not that it's of any
consequence.
--
terry morse Palo Alto, CA http://bike.terrymorse.com/

 

[[email protected]]

Can you elaborate on your Airless tire setup?

Tom

 

[David]

<[email protected]> wrote in message news:[email protected]...
>
> I, however, do and have found them to be super. When I'm riding to
> work in the dark, in the rain, I want to be 100% sure that I don't get
> a flat.
>
> The fact that they weigh more and have about 1% more rolling
> resistance, is of absolutely no consequence to me. I just want to get
> to where I'm going and arrive on time.

If it's only 1% more rolling resistance, I think they would beat Slime or tire liners.
Probably even beat the relatively puncture resistant kevlar-belted tires on my road bike.
I'm skeptical. I don't think it's impossible for there to be a good airless tire, but this
is the first glowing report I've read.

 

[Werehatrack]

On 13 Dec 2004 17:09:15 -0800, [email protected] wrote:

>>>>>
>Not exactly, "Airless" tires and tire conversions exist, but they are
>widely disparaged as being too stiff, too heavy, often too expensive,
>and usually too difficult to install.
><<<<
>
>Unfortunately this _is_ what a lot of people say but the truth is that
>most people _only_ say it _because_ they have read it in news groups
>like this. In truth, most people do not have first hand knowledge of
>Airless tires.
>
>I, however, do and have found them to be super. When I'm riding to
>work in the dark, in the rain, I want to be 100% sure that I don't get
>a flat.
>
>The fact that they weigh more and have about 1% more rolling
>resistance, is of absolutely no consequence to me. I just want to get
>to where I'm going and arrive on time.

The only adult-sized bike I've ridden which was equipped with airless
tires was an absolute slug, and having ridden an otherwise identical
bike that had conventional equipment, the tires had to be the reason.
I'll take the small risk of a flat on rare occasions in order to have
the intervening miles be significantly more pleasant to traverse.
Each of us has his own priorities; for those who have no problem with
(or don't perceive) the drawbacks of a product, there's nothing to be
gained by avoiding it. For others, there very well may be.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

 

[[email protected]]

>>
The only adult-sized bike I've ridden which was equipped with airless
tires was an absolute slug,
>>

I'll certainly admit that I have had this experience with 'some'
Airless tires but there are several different brands out there and they
are of varying quality.

It took some testing and experimenting but the ones I have used the
most are 27". This presents a problem for many people and I can
understand why.

Lewis.

********************

 

[Paul Kopit]

On 13 Dec 2004 17:09:15 -0800, [email protected] wrote:

>Unfortunately this _is_ what a lot of people say but the truth is that
>most people _only_ say it _because_ they have read it in news groups
>like this. In tru

I rode a set of Airless tires on a ride that used to be run here in
CA, The Great California Land Rush, in 1992. It went from San
Fransicso to Los Angeles in 2 days. That is over 200 mi/day.

I tested the tires before my outing by riding down a hill that I know
gave me 45-50 mi/hr with regular tires and the same speed was achieved
with the Airless tires and I assumed that the rolling resistance was
the same. They were some sort of foam with air cells. Also, the
tires wobbled and needed balancing like a car tires. I used lead
strips but never got it right. The mold for the tire must not have
been perfectly round. The tires were most difficult to mount. I
resorted to soaking them in very hot water before rolling the tire on.
I had to cut the tire to get it off.

I immediately lost the pack and suffered for 2 days. The tires were
both uncomfortable and didn't roll on the flat. I also attribute a
couple of broken spokes to the unyielding tire. The tire size was
700x20. The manufacturer, whose name I don't recall, made them in
Ontario, CA. The took them back and refunded $.

I don't mind flats that much. It only takes a few minutes to change
out a puncture. Should I want to sacrifice a lot, I'd use a 700x35 on
a commuter in the city. I believe that they sell many of these type
tires for wheel chairs.

 

[dkahn400]

Paul Kopit wrote:

> I tested the tires before my outing by riding down a hill that I know
> gave me 45-50 mi/hr with regular tires and the same speed was
achieved
> with the Airless tires and I assumed that the rolling resistance was
> the same. They were some sort of foam with air cells.

At that speed the effects of rolling resistance are completely swamped
by aerodynamic drag, which is why your results were misleading. It
might be interesting to try that hill again with your current favourite
tyres, first with them pumped up hard and then with them at half
pressure. I predict your terminal speed on the hill will be about the
same, but pedalling at around 10 mph on the flat the difference in drag
should be easily noticeable.

--
Dave...