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Dan Musicant
July 18th 03, 04:05 PM
Every bike I remember owning had 27 x 1.25 inch tires. When my old
Shwinn Continental frame broke almost 5 years ago I bought another used
road bike -- a Miyata, not a high end bike, but a pretty good quality
mass-production bike. It has a triple-butted frame of Chrome-Moly, fair
components but nothing special. The best thing is that it isn't
particularly thief bait and I don't have to be too nervous locking it up
outside in my town (Berkeley, CA).

Lately I've taken up daily 12 mile rides with about a 1000 foot mostly
gradual climb. The descent, however, is pretty steep. I've seen guys
blow by me at probably 35 miles/hour on the steepest part ( !! ) but it
makes me shudder to think what would happen to them if they had a flat
or a blowout. I read a story of a guy who's a quadrapalegic now who had
just such an accident in my vicinity.

Well, that story stuck with me and I don't want it happening to me. Of
course, there's just no being really safe on a bike, but I figure I can
start here by paying attention to my tires and not screaming down that
hill.

I had a blowout a couple days ago. I was at elevation and noticed some
bumping and saw a z-jag in my back tire and took it REAL slow down the
descent. I got to pretty flat elevation before the tire unexpectedly
blew out with what sounded like a gun shot. I just hopped off the bike,
locked it, and walked the rest of the way and came back and got it with
my car later.

That tire was not on that bike more than about a month. It was one of
several cheap tires I bought a few years ago and they seem to have all
gotten stiff, somewhat brittle and even crumbly just sitting around.
Does this always happen with bike tires? You can't buy them and store
them without them going bad? Is there something you can do to protect
them, like an application of Armor All? I also have many individual
packets of Turtle Wax Clear Guard protectant that I could try. I wonder
if anyone uses this stuff with either stored tires or tires that they
are riding in an effort to prolong their life.

I also have one not cheap new tire, a Michelin 27 x 1.38 inch tire, and
it too seems to have lost its suppleness and I'm afraid to try using it.
If I was just riding around the city I wouldn't be so afraid to just use
these new but apparently deteriorated tires and see what happens but
since I'm doing descents at sometimes pretty high speeds I don't want to
take unnecessary chances.

Another question I have is this: The place where I bought my used Miyata
said they could convert it to a 700cc bike to use the now common tire. I
assume that there's a whole lot more available in the 700 size, right?
I've been finding it hard to find anything in a 27 x 1.25. I bought a
couple at Orchard Supply yesterday, made in China I guess. They are
nothing special but at least the rubber seems fresh and vibrant.

Additional note: I use urethane tire liners (oversized), which I glue
into the tires with contact cement. I've been doing that for a number of
years and they seem to have reduced my flats by a factor of at least 3.

Thanks for your help, suggestions, etc.

Dan

Harris
July 18th 03, 04:29 PM
"Dan Musicant" wrote:
> Every bike I remember owning had 27 x 1.25 inch tires. When my old
> Shwinn Continental frame broke almost 5 years ago I bought another used

I thought those Continental frames were nuke proof.

> I had a blowout a couple days ago. I was at elevation and noticed some
> bumping and saw a z-jag in my back tire and took it REAL slow down the
> descent. I got to pretty flat elevation before the tire unexpectedly
> blew out with what sounded like a gun shot. I just hopped off the bike,
> locked it, and walked the rest of the way and came back and got it with
> my car later.

Was there a hole in the tire, or did it just blow off the rim? If it's the
latter, it may not have been seated properly on the rim. How much pressure
did you have in it? Do your rims have a hook bead? Also, your hard braking
on the descent could have heated the rims, causing the pressure to increase.

> That tire was not on that bike more than about a month. It was one of
> several cheap tires I bought a few years ago and they seem to have all
> gotten stiff, somewhat brittle and even crumbly just sitting around.
> Does this always happen with bike tires? You can't buy them and store
> them without them going bad? Is there something you can do to protect
> them, like an application of Armor All?

Keep the tires away from sunlight and ozone. Store them in a plastic bag in
a cool dry place and they'll last for years.

> Another question I have is this: The place where I bought my used Miyata
> said they could convert it to a 700cc bike to use the now common tire. I
> assume that there's a whole lot more available in the 700 size, right?

There are plenty of good 27 x 1-1/4" tires. Try the IRC Road Winners at
about $13.

Art Harris

Dan Musicant
July 18th 03, 08:15 PM
On Fri, 18 Jul 2003 15:29:28 GMT, "Harris" >
wrote:

:
:"Dan Musicant" wrote:
:> Every bike I remember owning had 27 x 1.25 inch tires. When my old
:> Shwinn Continental frame broke almost 5 years ago I bought another used
:
:I thought those Continental frames were nuke proof.

One day I was commuting in the city and around 4 miles from home and I
became aware that the down tube had cracked and really all the way
through right where it meets the bottom bracket. It was tough getting
home but I managed to do it, very slowly. It's almost 5 years so I don't
remember it well. I brought the frame to a local frame builder in the
hopes that he could save it but he told me to just get another bike, so
I accepted the death of my old Continental. It was a heavy brute,
anyway, but I was so used to it that it felt like part of my body - like
I had total control, like it was part of my nervous system. I guess you
get that way when you have one and only one bike for a long period of
time.
:
:> I had a blowout a couple days ago. I was at elevation and noticed some
:> bumping and saw a z-jag in my back tire and took it REAL slow down the
:> descent. I got to pretty flat elevation before the tire unexpectedly
:> blew out with what sounded like a gun shot. I just hopped off the bike,
:> locked it, and walked the rest of the way and came back and got it with
:> my car later.
:
:Was there a hole in the tire, or did it just blow off the rim? If it's the
:latter, it may not have been seated properly on the rim. How much pressure
:did you have in it? Do your rims have a hook bead? Also, your hard braking
:on the descent could have heated the rims, causing the pressure to increase.

It was really odd, actually. I saw an abrasion on the side of the tire
before it blew. The abrasion didn't go all the way through and I have no
idea how it got there. After it blew I saw what looked like a 2 inch
gash in the center of the tire (where it meets the pavement), and
longitudinal. There was a tire liner just inside that gash and the liner
looked fine - no hole or cut. The tube did not protrude through the
gash, as least not after the blowout. Inspecting the tube, I saw a hole
it in at least 1/4 inch in diameter and it was slightly town around that
hole. It was about the weirdest flat I've ever had because I couldn't
figure out exactly what went on, what went wrong.

I had inflated the tire to 75 lb (the recommended inflation) a few days
before, so it was probably around 70 - 75 lb. when I noticed the bumps,
and at that point I let a little air out to decrease the possibility of
a blowout, but probably not enough (that was my thought at the time,
that I should maybe let a little more out). I didn't have a guage with
me, although I did have a pump. I didn't want to have to pump more air
into it and just let it be. It was probably around 65 - 68 lb. when it
blew.

It didn't blow off the rim. True, the braking on the descent probably
increased the pressure. I wouldn't have thought of that.
:
:> That tire was not on that bike more than about a month. It was one of
:> several cheap tires I bought a few years ago and they seem to have all
:> gotten stiff, somewhat brittle and even crumbly just sitting around.
:> Does this always happen with bike tires? You can't buy them and store
:> them without them going bad? Is there something you can do to protect
:> them, like an application of Armor All?
:
:Keep the tires away from sunlight and ozone. Store them in a plastic bag in
:a cool dry place and they'll last for years.

I guess I'd need pretty big bags to store bike tires in or do you fold
the tires?

I don't know why, but all my old tires seem to get stiff and crumbly
after not too long.
:
:> Another question I have is this: The place where I bought my used Miyata
:> said they could convert it to a 700cc bike to use the now common tire. I
:> assume that there's a whole lot more available in the 700 size, right?
:
:There are plenty of good 27 x 1-1/4" tires. Try the IRC Road Winners at
:about $13.
:
:Art Harris

Thanks for the suggestion. I'll see if I can find them. Can I get them
online? There are a number of bike shops around here and maybe I'll be
able to find them there.

I'm way more concerned about having good tires now that I make that
descent every day. Normally I'm very secure on a bike even in the city
since I have a whole lot of city biking experience and I've learned to
stay out of trouble. But I can't think of any way to go down that road
without being nervous unless I go 4 miles/hour. The more I do it, the
more secure I feel going 20+ mph even in the steepest parts (I've seen
guys going 10-15 mph faster than me!), but I figure I could get messed
up royally if one of my tires blows, especially the front one.

Thanks for the ideas.

Dan

Rick Onanian
July 18th 03, 09:29 PM
I have similar concerns. I'm a little more reckless, and do go to 35 mph
and beyond, but I notice that my Hutchinson Carbon Comp 700c X 23 tires,
from 2001, have some cracking where the sidewall meets the tread. They hold
125psi (their rated max, and the pressure I run) fine, and the only issue
I've had is a flat from going up a sharp curb too hard (the presta valve
stopped holding air). I've been trusting that the belt will hold them
together, as well as the interior rubber and anything else that's not
cracked (just that exterior layer of rubber).

Should I replace these tires? If so, how can I maintain their condition
better? I suspect a standard commercially available rubber treatment for
automotive tires should suffice.

On Fri, 18 Jul 2003 15:05:38 GMT, Dan Musicant
> wrote:

> blow by me at probably 35 miles/hour on the steepest part ( !! ) but it
> makes me shudder to think what would happen to them if they had a flat
> or a blowout. I read a story of a guy who's a quadrapalegic now who had
> just such an accident in my vicinity.
>
> That tire was not on that bike more than about a month. It was one of
> several cheap tires I bought a few years ago and they seem to have all
> gotten stiff, somewhat brittle and even crumbly just sitting around.

--
Rick Onanian

Eric Murray
July 18th 03, 11:38 PM
In article >,
Dan Musicant > wrote:
>them without them going bad? Is there something you can do to protect
>them, like an application of Armor All? I also have many individual
>packets of Turtle Wax Clear Guard protectant that I could try. I wonder
>if anyone uses this stuff with either stored tires or tires that they
>are riding in an effort to prolong their life.

I wouldn't do that. Those "protectants" make rubber
(or vinyl) very slick. Not good for traction!

If you store tires in a dark cool place and away from ozone
(i.e. electric motors) they last for a while.

>I also have one not cheap new tire, a Michelin 27 x 1.38 inch tire, and
>it too seems to have lost its suppleness and I'm afraid to try using it.

I would be too.

>If I was just riding around the city I wouldn't be so afraid to just use
>these new but apparently deteriorated tires and see what happens but
>since I'm doing descents at sometimes pretty high speeds I don't want to
>take unnecessary chances.

Speaking of chances, do you have reasonably fresh brake pads?


Eric

Harris
July 19th 03, 02:56 AM
"Dan Musicant" wrote:
> I guess I'd need pretty big bags to store bike tires in or do you fold
> the tires?

Even wire bead tires can be coiled in a way that makes them easy to store.

See: http://draco.acs.uci.edu/rbfaq/FAQ/8b.23.html


> :There are plenty of good 27 x 1-1/4" tires. Try the IRC Road Winners at
> :about $13.
> :
> :Art Harris
>
> Thanks for the suggestion. I'll see if I can find them. Can I get them
> online?

Yes, Nashbar has them on sale. I just bought some today in 700 x 28, but
they also have them in 27 x 1-1/8" and 27 x 1-1/4".

See: http://www.nashbar.com The stock number is IR-RWD.

Art Harris

Dan Musicant
July 19th 03, 03:20 AM
On Fri, 18 Jul 2003 22:38:43 GMT, (Eric Murray) wrote:

:In article >,
:Dan Musicant > wrote:
:>them without them going bad? Is there something you can do to protect
:>them, like an application of Armor All? I also have many individual
:>packets of Turtle Wax Clear Guard protectant that I could try. I wonder
:>if anyone uses this stuff with either stored tires or tires that they
:>are riding in an effort to prolong their life.
:
:I wouldn't do that. Those "protectants" make rubber
:(or vinyl) very slick. Not good for traction!
:
:If you store tires in a dark cool place and away from ozone
:(i.e. electric motors) they last for a while.
:
:>I also have one not cheap new tire, a Michelin 27 x 1.38 inch tire, and
:>it too seems to have lost its suppleness and I'm afraid to try using it.
:
:I would be too.
:
:>If I was just riding around the city I wouldn't be so afraid to just use
:>these new but apparently deteriorated tires and see what happens but
:>since I'm doing descents at sometimes pretty high speeds I don't want to
:>take unnecessary chances.
:
:Speaking of chances, do you have reasonably fresh brake pads?

Probably not fresh enough, now that you mention it. There's one part of
the descent where there's a traffic signal. It's usually green, but when
it's not I have trouble stopping in time. Cars have no problem. I think
I better switch out my brake pads. Thanks.

Dan
:
:Eric
:

Phil, Squid-in-Training
July 19th 03, 03:25 AM
> Probably not fresh enough, now that you mention it. There's one part of
> the descent where there's a traffic signal. It's usually green, but when
> it's not I have trouble stopping in time. Cars have no problem. I think
> I better switch out my brake pads. Thanks.

Oh come on! Have a little excitement in your life! Be a little
dangerous... chicks dig that.

--
Phil, Squid-in-Training

John Albergo
July 19th 03, 05:16 PM
Dan Musicant wrote:

>
>I don't know why, but all my old tires seem to get stiff and crumbly
>after not too long.
>
>
Ozone.

>
>

Dan Musicant
July 19th 03, 08:31 PM
On Sat, 19 Jul 2003 02:25:33 GMT, "Phil, Squid-in-Training" >
wrote:

:> Probably not fresh enough, now that you mention it. There's one part of
:> the descent where there's a traffic signal. It's usually green, but when
:> it's not I have trouble stopping in time. Cars have no problem. I think
:> I better switch out my brake pads. Thanks.
:
:Oh come on! Have a little excitement in your life! Be a little
:dangerous... chicks dig that.

No doubt about it. In fact I met one the other day by virtue of telling
her about my blowout adventure.

mark freedman
July 20th 03, 01:35 AM
Dan Musicant > wrote in message >...

>>
> Lately I've taken up daily 12 mile rides with about a 1000 foot mostly
> gradual climb. The descent, however, is pretty steep. I've seen guys
> blow by me at probably 35 miles/hour on the steepest part ( !! ) but it

You may want to read the section on descending in the rec.bicycles
faq.
Tips on techniques etc.

The following clip discusses heating and clincher tires lifting off
the rims. It doesn't sound like that was your problem, but the
implications of increased tire pressure are interesting. Also, if you
use tires intended for hooked rims on older smooth rims, they may be
more prone to lifting off.
================================================== ======================

This is a serious problem both for tubulars and clinchers because most
clincher tires, given enough time on a hot rim will blow off if
inflated to recommended pressure. Pressure that gives good rolling
performance (hard) while tubulars roll off from lack of adhesion to
the rim. The faster the travel, the more descending power goes into
wind drag and the better the rims are cooled. Going slowly does not
help, unless speed is reduced below walking pace.

On steep descents, where rims stay too hot to touch for more than a
minute, reducing tire inflation pressure is a sure remedy. However,
tires should be re-inflated once the rims cool to normal. The
blow-off pressure is the same for small and large tires on the same
rim, it being dependent only on the opening of the rim width. Also,
tires with a smaller air volume become hot faster than larger ones.

There is no way of descending continuously and steeply without
reducing inflation pressure, unless there is an insulator between the
tube and rim of a clincher. Insulating rim strips are no longer
offered because they were an artifact of dirt roads that often
required riders to descend so slowly that all potential energy went
into the brakes and almost none into wind drag. These rim strips were
cloth tubes filled with kapok, their insulating purpose being unknown
to most people when they were last offered.
================================================== =====================

> makes me shudder to think what would happen to them if they had a flat

You need the new Voler par la Nuit airbag helmet. If an impact is
severe enough to cause serious injury, the airbags detonate and crush
your skull so that some misguided paramedic won't have anything to
revive.

For some reason, we're having toruble getting it approved for sale.


>>
>> Does this always happen with bike tires? You can't buy them and
store

Chemicals such as ozone, probably UV exposure would affect rubber.
I believe storing in a basement where furnace or water heater fumes
are present would reduce the shelf life. Probably discussed elsewhere.



> >
> said they could convert it to a 700cc bike to use the now common tire. I

Discussed at www.sheldonbrown.com as well as here (google groups
search).
Your brakes may not have enough reach for the smaller rims. You may do
this to upgrade from freewheel to freehub/cassette, or just better
quality wheels.

I recall some 27" tires at harris cyclery (sheldonbrown). Locally,
I can buy a $5 tire rated at 90 psi, or a $30 kevlar-belted tire, or
several in between. There are a lot of cheap / heavy 27" tires as
well, sold by Canadian Tire, Wal-Mart, aned other retailers of "top
quality" cycling products :-)

> assume that there's a whole lot more available in the 700 size, right?

More choices. I don't consider the cost of upgrading justified only
to have more choice in tires. It is an opportunity to get better
wheels and freehub/cassette, etc.


>> years and they seem to have reduced my flats by a factor of at
least 3.
>
I liked the Hutchinson Globetrotter 700*28's for ride and
(relative) durability. Vredstein Perfect 700*28's were more puncture
resistant (special non-Kevlar belt). Vredstein Perfect 700*32's are
"designed" in Holland, probably made in China, and are not as
enjoyable a ride. Fairly bulletproof, though. Some of the puncture
resistance (glass, road debris) is due to the tread, some due to the
special belt.

I've considered Panaracer Pasela Tourguard with the Kevlart belt,
but some people have posted here that they had lots of flats when they
tried them.

No idea about "high performance" tires, i.e. narrower, lighter,
smoother or no tread.

ymmv

David L. Johnson
July 20th 03, 03:19 AM
On Fri, 18 Jul 2003 15:05:38 +0000, Dan Musicant wrote:

> Lately I've taken up daily 12 mile rides with about a 1000 foot mostly
> gradual climb. The descent, however, is pretty steep. I've seen guys blow
> by me at probably 35 miles/hour on the steepest part ( !! ) but it makes
> me shudder to think what would happen to them if they had a flat or a
> blowout. I read a story of a guy who's a quadrapalegic now who had just
> such an accident in my vicinity.

35mph is not that fast. Anything can happen in any accident, of course,
but usually a fall at that speed will only scrape off a lot of skin, maybe
break a collar bone. There may have been other circumstances with the guy
who is now a quadraplegic, or it may have been a tragically bad landing.
>
> Well, that story stuck with me and I don't want it happening to me. Of
> course, there's just no being really safe on a bike,

On balance, cycling is very safe. There is no being "really safe"
driving, either, or walking across the street. You have to decide what
level of risk life is worth, and live your life accordingly.

> I had a blowout a couple days ago. I was at elevation and noticed some
> bumping and saw a z-jag in my back tire and took it REAL slow down the
> descent. I got to pretty flat elevation before the tire unexpectedly
blew

unexpectedly? It's got this big bulge pushing it sideways and a blowout
is unexpected? Next time, when you see a seriously deformed tire, stop
right away and fix it. It is stupid to try to downhill with a tire like
that.

There are things you can do to repair such a tire. The casing broke, for
some reason. Could be a cut, or maybe it was installed incorrectly, or
perhaps it was defective. Carry with you some material to "boot" the
tire, which means to place a layer of strong material between the tire and
the tube, to shore up the damaged casing. A part of the casing of an old
tire is best (with the rubber tread removed), but there are some
commercial boot material packages that are quite good. In an emergency,
paper money, power-bar wrappers, and all sorts of similar material can be
used. Find a soda bottle by the side of the road, or cut a square out of
a water bottle. It will get you home.

> Another question I have is this: The place where I bought my used Miyata
> said they could convert it to a 700cc bike to use the now common tire. I
> assume that there's a whole lot more available in the 700 size, right?

True

> I've been finding it hard to find anything in a 27 x 1.25. I bought a
> couple at Orchard Supply yesterday, made in China I guess. They are
> nothing special but at least the rubber seems fresh and vibrant.

But they are junk, and will slow you down.
>
> Additional note: I use urethane tire liners (oversized), which I glue into
> the tires with contact cement. I've been doing that for a number of years
> and they seem to have reduced my flats by a factor of at least 3.

All these miracle treatments to stop flats are compromises. That stuff,
again, slows you down. It makes it harder to ride. And, no matter what,
you will still have flats. Some hazards can get by anything.

There are a few simple riding techniques that cut down the flats without
slowing you down. Obviously, the first is to watch out carefully for
hazards, potholes, glass, etc., and avoid them. When a rough road is
unavoidable, get out of the saddle to lessen the impact on the tires.
Learn how to jump over obstacles.

--

David L. Johnson

__o | We have a record of conquest, colonization and expansion
_`\(,_ | unequalled by any people in the Nineteenth Century. We are not
(_)/ (_) | to be curbed now. --Henry Cabot Lodge, 1895

A Muzi
July 20th 03, 02:19 PM
"Dan Musicant" > wrote in message
...
> Every bike I remember owning had 27 x 1.25 inch tires. When my old
> Shwinn Continental frame broke almost 5 years ago I bought another used
> road bike -- a Miyata, not a high end bike, but a pretty good quality
> mass-production bike. It has a triple-butted frame of Chrome-Moly, fair
> components but nothing special. The best thing is that it isn't
> particularly thief bait and I don't have to be too nervous locking it up
> outside in my town (Berkeley, CA).
>
> Lately I've taken up daily 12 mile rides with about a 1000 foot mostly
> gradual climb. The descent, however, is pretty steep. I've seen guys
> blow by me at probably 35 miles/hour on the steepest part ( !! ) but it
> makes me shudder to think what would happen to them if they had a flat
> or a blowout. I read a story of a guy who's a quadrapalegic now who had
> just such an accident in my vicinity.
>
> Well, that story stuck with me and I don't want it happening to me. Of
> course, there's just no being really safe on a bike, but I figure I can
> start here by paying attention to my tires and not screaming down that
> hill.
>
> I had a blowout a couple days ago. I was at elevation and noticed some
> bumping and saw a z-jag in my back tire and took it REAL slow down the
> descent. I got to pretty flat elevation before the tire unexpectedly
> blew out with what sounded like a gun shot. I just hopped off the bike,
> locked it, and walked the rest of the way and came back and got it with
> my car later.
>
> That tire was not on that bike more than about a month. It was one of
> several cheap tires I bought a few years ago and they seem to have all
> gotten stiff, somewhat brittle and even crumbly just sitting around.
> Does this always happen with bike tires? You can't buy them and store
> them without them going bad? Is there something you can do to protect
> them, like an application of Armor All? I also have many individual
> packets of Turtle Wax Clear Guard protectant that I could try. I wonder
> if anyone uses this stuff with either stored tires or tires that they
> are riding in an effort to prolong their life.
>
> I also have one not cheap new tire, a Michelin 27 x 1.38 inch tire, and
> it too seems to have lost its suppleness and I'm afraid to try using it.
> If I was just riding around the city I wouldn't be so afraid to just use
> these new but apparently deteriorated tires and see what happens but
> since I'm doing descents at sometimes pretty high speeds I don't want to
> take unnecessary chances.
>
> Another question I have is this: The place where I bought my used Miyata
> said they could convert it to a 700cc bike to use the now common tire. I
> assume that there's a whole lot more available in the 700 size, right?
> I've been finding it hard to find anything in a 27 x 1.25. I bought a
> couple at Orchard Supply yesterday, made in China I guess. They are
> nothing special but at least the rubber seems fresh and vibrant.
>
> Additional note: I use urethane tire liners (oversized), which I glue
> into the tires with contact cement. I've been doing that for a number of
> years and they seem to have reduced my flats by a factor of at least 3.

There are plenty of 27" tires available from Kenda gumwalls ( under $10) to
the very nice Panaracer and Inoue-IRC tires in 27x1, 27x1-1/8, 27x1-1/4
(both offer kevlar under the tread if you are so inclined), the Michelin
World Tour you noted that's quite an ample version of 27x1-1/4 and then all
the knobby 27x1-1/3 tires. There are several other brands available as well
.. On an older bike the expense of new wheels is not always appropriate where
the existing equipment is in good condition.

(BTW fractions and decimals are used to denote different series of rims in
our industry - you shouldn't mix them)

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

Dan Musicant
July 20th 03, 04:41 PM
On Sat, 19 Jul 2003 22:19:22 -0400, "David L. Johnson"
> wrote:

:On Fri, 18 Jul 2003 15:05:38 +0000, Dan Musicant wrote:
:
:> Lately I've taken up daily 12 mile rides with about a 1000 foot mostly
:> gradual climb. The descent, however, is pretty steep. I've seen guys blow
:> by me at probably 35 miles/hour on the steepest part ( !! ) but it makes
:> me shudder to think what would happen to them if they had a flat or a
:> blowout. I read a story of a guy who's a quadrapalegic now who had just
:> such an accident in my vicinity.
:
:35mph is not that fast. Anything can happen in any accident, of course,
:but usually a fall at that speed will only scrape off a lot of skin, maybe
:break a collar bone. There may have been other circumstances with the guy
:who is now a quadraplegic, or it may have been a tragically bad landing.

I do reach 35 mph on a lower portion of the descent, but at that point
that's the maximum speed I can achieve and it doesn't worry me as much.
However I've seen guys achieve a similar speed earlier in the descent
where it's far steeper (probably twice as steep), where it's impossible
to not use the brakes, and with that steepness, a crash at 35 mph would
be a worse matter since you would be rolling and tumbling down a steep
incline and have gravity to fight at a whole different level in trying
to come to a halt and stop the damage. It's hard for me to imagine
escaping such an event without catastrophic injuries, is what I'm
saying. Maybe where it's not so steep, surviving a 35 mph crash is not
such a problem.

The guy who is a quadrapalegic now is Ralph Parker, and his wife Susie
wrote the cover story in an edition of the East Bay Express (and it must
be about 2 - 3 years ago now) about the aftermath of the crash. He was
coming off Skyline Blvd. and made a left turn onto Claremont Ave., which
abruptly makes a descent there, and at that point he had his blowout. He
was unable to control the bike and ran onto the shoulder and the bike
flipped and he landed on his head. He was wearing a helmet. He's
practically if not absolutely helpless without human aid.
:>
:> Well, that story stuck with me and I don't want it happening to me. Of
:> course, there's just no being really safe on a bike,
:
:On balance, cycling is very safe. There is no being "really safe"
:driving, either, or walking across the street. You have to decide what
:level of risk life is worth, and live your life accordingly.

I think what bothers me is that there doesn't seem to be anything I can
do if that blowout happens at the wrong time. I try to leave a safety
zone when I drive or walk or rollerskate or bike in the city, so that I
can react if a dangerous situation arises. A steep bike descent doesn't
seem to have anything like that. No time to react and protect yourself,
or practically none. I always wear full leather gloves so that at least
I wouldn't scrape the skin off my hands if I had to break fall, and it's
helped a couple times.
:
:> I had a blowout a couple days ago. I was at elevation and noticed some
:> bumping and saw a z-jag in my back tire and took it REAL slow down the
:> descent. I got to pretty flat elevation before the tire unexpectedly
:blew
:
:unexpectedly? It's got this big bulge pushing it sideways and a blowout
:is unexpected? Next time, when you see a seriously deformed tire, stop
:right away and fix it. It is stupid to try to downhill with a tire like
:that.

The only way I could have fixed it was to leave the bike up there and
hitch a ride down the hill. Doable, but I figured I'd chance a VERY SLOW
descent. On balance, considering what happened, I think even that was
probably foolhardy. I didn't go over around 4 or 5 mph on the steep
part, though. I've had similar deformed tires that didn't blow, so I
figured I was probably OK to get home. I was wrong, at least this time.
:
:There are things you can do to repair such a tire. The casing broke, for
:some reason. Could be a cut, or maybe it was installed incorrectly, or
:perhaps it was defective. Carry with you some material to "boot" the
:tire, which means to place a layer of strong material between the tire and
:the tube, to shore up the damaged casing. A part of the casing of an old
:tire is best (with the rubber tread removed), but there are some
:commercial boot material packages that are quite good.

I carry a kit with me, actually a couple these days. One is attached to
the underside of me seat and it has a piece of plastic, about 3/4 inch
by 2 inches, to bridge a cut in the tire.

: In an emergency,
:paper money, power-bar wrappers, and all sorts of similar material can be
:used. Find a soda bottle by the side of the road, or cut a square out of
:a water bottle. It will get you home.

Good ideas!
:
:> Another question I have is this: The place where I bought my used Miyata
:> said they could convert it to a 700cc bike to use the now common tire. I
:> assume that there's a whole lot more available in the 700 size, right?
:
:True
:
:> I've been finding it hard to find anything in a 27 x 1.25. I bought a
:> couple at Orchard Supply yesterday, made in China I guess. They are
:> nothing special but at least the rubber seems fresh and vibrant.
:
:But they are junk, and will slow you down.

Honestly, I don't care about the slow down. I only care about being
safe. I've never raced a bike and don't expect to. I race myself, use a
bike computer to note how fast I'm doing, time elapsed at different
milestones in my ride, but it's all relative, and if a tire is slowing
me down 5%, I don't care. But an injurious accident does concern me. The
only time I was hurt on a bike that I can remember was when I was about
12 - 13 years old. I was going down a hill and somehow, unexpectedly and
without warning, the fork began to oscillate from side to side, The
oscillation amplified until the bike went down. I was unaware of having
done anything dangerous or out of the ordinary. It happened in a second
and the next thing I knew I was on someone's couch. It was a block from
my home and I had a cut on my lip with a few stiches. Nobody at school
would believe I wasn't in a fight!

:>
:> Additional note: I use urethane tire liners (oversized), which I glue into
:> the tires with contact cement. I've been doing that for a number of years
:> and they seem to have reduced my flats by a factor of at least 3.
:
:All these miracle treatments to stop flats are compromises. That stuff,
:again, slows you down. It makes it harder to ride. And, no matter what,
:you will still have flats. Some hazards can get by anything.

There's no way to objectively evaluate the advantages or disadvantages
of my using urethane tire liners glued into my tires but my sense of it
is that I've been getting 30% or less flats than I was getting before I
started using them.

:
:There are a few simple riding techniques that cut down the flats without
:slowing you down. Obviously, the first is to watch out carefully for
:hazards, potholes, glass, etc., and avoid them. When a rough road is
:unavoidable, get out of the saddle to lessen the impact on the tires.
:Learn how to jump over obstacles.

Sometimes, when I've found riding over glass shards unavoidable, I place
my gloved hand on the tires (while riding!) to dislodge shards that
might not yet have worked into the tires. It's just such shards, BTW,
that the urethane liners are so good at protecting the tubes from. But
even liners are not 100% effective at protecting from glass.

I think the quality of the tube is important, too. I've been finding it
hard to find quality 27 x 1.25 tubes - another reason to convert to
700's.

Tom Sherman
July 20th 03, 06:47 PM
Dan Musicant wrote:
> ...
> I think what bothers me is that there doesn't seem to be anything I can
> do if that blowout happens at the wrong time. I try to leave a safety
> zone when I drive or walk or rollerskate or bike in the city, so that I
> can react if a dangerous situation arises. A steep bike descent doesn't
> seem to have anything like that. No time to react and protect yourself,
> or practically none. I always wear full leather gloves so that at least
> I wouldn't scrape the skin off my hands if I had to break fall, and it's
> helped a couple times....

If you are really worried about falling due to tire failure, the
solution is to add a third wheel. Of course, there is a whole set of
trade-offs that you may or may not find acceptable.

Tom Sherman - Quad Cities USA (Illinois side)

Dan Musicant
July 21st 03, 04:42 PM
On Sat, 19 Jul 2003 01:56:20 GMT, "Harris" >
wrote:

:
:"Dan Musicant" wrote:
:> I guess I'd need pretty big bags to store bike tires in or do you fold
:> the tires?
:
:Even wire bead tires can be coiled in a way that makes them easy to store.
:
:See: http://draco.acs.uci.edu/rbfaq/FAQ/8b.23.html
:
:
:> :There are plenty of good 27 x 1-1/4" tires. Try the IRC Road Winners at
:> :about $13.
:> :
:> :Art Harris
:>
:> Thanks for the suggestion. I'll see if I can find them. Can I get them
:> online?
:
:Yes, Nashbar has them on sale. I just bought some today in 700 x 28, but
:they also have them in 27 x 1-1/8" and 27 x 1-1/4".
:
:See: http://www.nashbar.com The stock number is IR-RWD.
:
:Art Harris

What kind of tires are IRC Road Winners? Are they especially safe? Looks
like in 27 x 1.25 they are 95 lb. inflation. What I want most in a tire
is dependability, reliability, resistance to blowouts and longevity. It
would be nice to have some way of guaging when it's time to replace
them, but I guess that's a judgment call I'm just going to have to make
myself.

Dan

Precious Pup
July 21st 03, 08:13 PM
Dan Musicant wrote:
>

> I think what bothers me is that there doesn't seem to be anything I can
> do if that blowout happens at the wrong time.

It is true, there isn't much you can do. It is however, quite rare. If you want, you can stop and inspect
your wheels before each significant descent. That isn't even a bad idea if you have _decent_ reason to
believe your sidewalls may have been cut, or similar. Also, one must take care that the tubes are installed
properly. I suspect more blowouts are due to faulty tube installation than any other reason. As a matter of
practice, inspect tires before each ride (or essentially after the previous ride) for large cuts and/or
deformation.

> :unexpectedly? It's got this big bulge pushing it sideways and a blowout
> :is unexpected? Next time, when you see a seriously deformed tire, stop
> :right away and fix it. It is stupid to try to downhill with a tire like
> :that.

Exactly. I saw a bulge in one of my tires (a Michelin AxPro) after a recent inspection. There was no
external cut. Removing and inspecting it from the inside revealed a casing tear. I threw it away. This is
the first time in 25+ years of "serious riding" I've seen a tear of this nature. I'm standardizing on Conti
Grand Sport and Avocet Carbon 12 tires for racing/training. I've tried so many different kinds -- these seem
to have the right balance of durability and performance. In fact they don't seem to sacrifice much in any
department unless extreme light weight is the prime concern. There are some bigger tires that seem cool too
-- like the Roly Poly and Pasela with Kevlar. I haven't used the Pasela; I mean to try them on my
touring/commuter bike.

> The only way I could have fixed it was to leave the bike up there and
> hitch a ride down the hill.

No real excuse. You could have:

1. Booted with old casing taken along just for that purpose.
2. Ride very slowly. (Which you chose.)


> I carry a kit with me, actually a couple these days. One is attached to
> the underside of me seat and it has a piece of plastic, about 3/4 inch
> by 2 inches, to bridge a cut in the tire.

So???? Why didn't you use it at the bulge?

> Honestly, I don't care about the slow down. I only care about being
> safe. I've never raced a bike and don't expect to. I race myself, use a
> bike computer to note how fast I'm doing, time elapsed at different
> milestones in my ride, but it's all relative, and if a tire is slowing
> me down 5%, I don't care. But an injurious accident does concern me.

That's fine. But you can get better tires (lower rolling resistance and weight) that will likely have just as
much (or more) resistance to similar problems. Remember, those are the cheapest tires you purchased. "Good
deals" can surely be had, but there might be something to that old aphorism "you get what you pay for" from
time to time.

> There's no way to objectively evaluate the advantages or disadvantages
> of my using urethane tire liners glued into my tires but my sense of it
> is that I've been getting 30% or less flats than I was getting before I
> started using them.

Punctures, per se, aren't a severe danger, because almost without exception punctures allow you time, and
simply looking down at your tires and "feeling" them can easily reveal a deflating tire. Just stop and fix
them. The only severe danger is rapid deflation that essentially allows no time to react (a "blowout").

> Sometimes, when I've found riding over glass shards unavoidable, I place
> my gloved hand on the tires (while riding!) to dislodge shards that
> might not yet have worked into the tires.

I doubt this is helpful. If it gets lodged in, it will do so before you have a chance to wipe it off. Stop
and inspect if you hear clicking or the like. Or stop and inspect if it simply makes you feel better. Gain
confidence by following your own instincts and responding to your own comfort level. You can and should
listen to the experience of others, and that is well and good, but ultimately you must satisfy yourself.

> It's just such shards, BTW,
> that the urethane liners are so good at protecting the tubes from. But
> even liners are not 100% effective at protecting from glass.

If you want them, that is fine with me. I don't use them, nor do "most" experienced riders if that tells you
anything.

> I think the quality of the tube is important, too. I've been finding it
> hard to find quality 27 x 1.25 tubes - another reason to convert to
> 700's.

Agreed. There is probably little point in swimming against the tide for this particular component. In fact,
one should have very compelling reasons for any "oddball" decisions.

Douglas Landau
July 23rd 03, 02:05 AM
> > I think what bothers me is that there doesn't seem to be anything I can
> > do if that blowout happens at the wrong time.
>
> It is true, there isn't much you can do. It is however, quite rare. If you want, you can stop and inspect
> your wheels before each significant descent.


Ahhh - Finally!!! I've been wondering if I am the only one who approaches
the problem this way.

I am terrified of wiping out at speed but still I descend my local mountain
at 44-46 regularly and don't worry about blowouts. Or rather, I DO worry
about them, depending on how you look at it. I go through this routine
every day (ok, every ride) before descending:

- Hold rear brake and lift front wheel up to eye level. Spin tire slowly
and inspect at every inch. Does anything about it look different in
any way than yesterday?
- spin front wheel and bang each spoke with fingernail. Any coming loose?
- Check front quick release - has come open?
- Grab front wheel and shake it. Is it really on tight?
- Squeeze front brakes. Working well?
- Put front wheel between feet and lift rear wheel/hold at eye level.
- Spin rear wheel slowly and inspect every inch. Any new cuts? Any small
cracks getting big? Any sidewall damage? Any cuts or cracks allowing
any of the material under the rubber to contact the road? Any thorns
or bits of glass? most importantly, IS THERE ANY CONDITION WHICH IS
CHANGING RAPIDLY?
- spin rear wheel and bang spokes with fingernail. Any coming looose?
- check rear quick-release - has come open? Grab rear wheel and shake it.
- Squeeze rear brakes: working well?

I'll crawl home and then replace the tire immediately if I see any:
- bulges
- sidewall damage
- cuts or cracks which will allow any part of the tire which is not rubber
to contact the road
- cuts or cracks which are changing rapidly.

The only time I ever have to crawl home is when I get a new glass cut on
the way up the hill. Anything else, you can watch develop.


Doug

Precious Pup
July 24th 03, 01:45 AM
Douglas Landau wrote:
>
> > > I think what bothers me is that there doesn't seem to be anything I can
> > > do if that blowout happens at the wrong time.
> >
> > It is true, there isn't much you can do. It is however, quite rare. If you want, you can stop and inspect
> > your wheels before each significant descent.
>
> Ahhh - Finally!!! I've been wondering if I am the only one who approaches
> the problem this way.


Wait a minute. I didn't quite say "that is what I do." I've done it a *few* times in 25+ years of riding.

Art Harris
July 24th 03, 09:56 PM
Dan Musicant wrote:
> I think the quality of the tube is important, too. I've been finding it
> hard to find quality 27 x 1.25 tubes - another reason to convert to
> 700's.

No! 700c tubes can be used in 27" tires without a problem. Look for a
700 x 32 tubes for your 27 x 1-1/4" tires. If you can get thorn
resistant tubes, you will get excellent flat protection. Thorn
resistant tubes are very heavy, but I think you're more concerned with
durability than weight.

See: http://www.performancebike.com/shop/Profile.cfm?SKU=1869&Store=Bike

Art Harris

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