Tire liner penalty?
Bob
use Mr. Tuffy's since I commute on the bike (Contis on a 700X25c)and
I've had very few flats. Will taking out the tire liners make much of a
difference in rolling resistance or acceleration? The bike (Trek 2120)
will be loaded for light touring on a 285-mile timed ride with plenty
of hills.
Thanks,
Bob
--
www.homestead.com/greenstlouis
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
Paul Kopit
significant difference when they are removed. The same hold true for
riders that use belted tires.
In both cases, the tires do have higher rolling resistance but it's
not until you get into accellerating the bicycle or thundering through
corners that you'll know the difference.
Flatting is part of riding and changing out a flat is not something to
be feared.
Bob
liners. (Broken glass as a road surface: Who'd a thunk?) And on the
cross-state ride, I really would rather not have to change a flat at
three in the morning 10 miles outside Cowsquat, Missouri. So, I'm
trying to weigh the increased convenience of tire liners against trying
to optimize the bike's (and my) performance. I was surprised to see
there wasn't any discussion of this in the FAQ or any threads.
Bob
In article <37bbab3c....@netnews.att.net>,
paul-...@att.net wrote:
> Most riders that regularly use Mr. Tuffy's will not notice a
> significant difference when they are removed. The same hold true for
> riders that use belted tires.
>
> In both cases, the tires do have higher rolling resistance but it's
> not until you get into accellerating the bicycle or thundering through
> corners that you'll know the difference.
>
> Flatting is part of riding and changing out a flat is not something to
> be feared.
>
--
David T. Blake
> Most riders that regularly use Mr. Tuffy's will not notice a
> significant difference when they are removed. The same hold true
> for riders that use belted tires.
I've always noticed a fairly large difference. Mr Tuffy tire
liners suck energy big time, even compared to kevlar belts.
--
Dave Blake
dbl...@phy.ucsf.edu
Mark Atanovich
paul-...@att.net (Paul Kopit) writes:
> Flatting is part of riding and changing out a flat is not something to
> be feared.
It is when you're late for work and get a flat in 75 degree dew point
weather.
Mark Atanovich
"Good judgement comes from experience. Experience comes from bad
judgement."
Ray Bowman
dbl...@phy.ucsf.edu
wrote:
>I've always noticed a fairly large difference. Mr Tuffy tire
>liners suck energy big time, even compared to kevlar belts.
Some years back Dr. Kyle made rolling resistance measurements for quite a few
tires -- and also a few tires with and without tire liners. His measurements
have been published (including in Bicycling Mag, I think) as he has a generally
good rep as a scientist. He found that tire liners installed in narrow tires
(typical road bike tires) essentially doubled their rolling resistance.
Ray
Also, the University of Michigan, back 1993, tested tire liners on their
SunRaycer (Solar powered cars using bike wheels) and could see substantial
increases in the rolling resistance of their vehicle. They used sealant filled
tubes instead (made by me for them) and were very pleased with the result:
negigible increase in rolling resistance and better flat protection.
Paul Kopit
that using a wider tire, i.e., 700x28 reduced flats. A big help is
also using a bigger tube. Most 27" tubes are for 700x20-18 tires.
The next size up is for 700x28 and higher. If you stuff the larger
tube into your tire, you will get fewer flats. The tube gets less
stretched and theres just more rubber between the road and airspace.
Change your tires when they are 75% worn out. Most flats seem to
occur in the latter part of a tires life.
James Connell
rolling resistance, but it's acceleration that suffers most.
Bob wrote:
>
> Well on my commute, flats *are* something to be feared, hence the tire
> liners. (Broken glass as a road surface: Who'd a thunk?) And on the
> cross-state ride, I really would rather not have to change a flat at
> three in the morning 10 miles outside Cowsquat, Missouri. So, I'm
> trying to weigh the increased convenience of tire liners against trying
> to optimize the bike's (and my) performance. I was surprised to see
> there wasn't any discussion of this in the FAQ or any threads.
>
> Bob
>
> In article <37bbab3c....@netnews.att.net>,
> paul-...@att.net wrote:
> > Most riders that regularly use Mr. Tuffy's will not notice a
> > significant difference when they are removed. The same hold true for
> > riders that use belted tires.
> >
> > In both cases, the tires do have higher rolling resistance but it's
> > not until you get into accellerating the bicycle or thundering through
> > corners that you'll know the difference.
> >
> > Flatting is part of riding and changing out a flat is not something to
> > be feared.
> >
>
> --
> www.homestead.com/greenstlouis
>
> Sent via Deja.com http://www.deja.com/
> Share what you know. Learn what you don't.
--
James Connell
Do not Fold, Spindle, or Mutilate.
The opinions expressed herein do not necessarily
reflect those of the author.
Mike Jacoubowsky
it's made of concrete...much less supple, more road noise, generally harsh
ride. I've noticed this pretty much across the board, although the effect
is far more obnoxious on a narrower road tire.
--Mike--
Chain Reaction Bicycles
http://www.ChainReactionBicycles.com
Ray Bowman <rayb...@aol.com> wrote in message
news:19990814182512...@ng-bh1.aol.com...
Damon Rinard
> I'm getting ready to put on new tires for some long rides. Currently
> I use Mr. Tuffy's since I commute on the bike (Contis on a 700X25c)
> and I've had very few flats. Will taking out the tire liners make much
> of a difference in rolling resistance or acceleration? The bike (Trek
> 2120) will be loaded for light touring on a 285-mile timed ride with
> plenty of hills.
>
> Thanks,
> Bob
Ray Bowman gave Chester Kyle's Rolling Resistance measurements in a post
to Hardcore Bicycle Science ( http://sheldonbrown.com/hbs.html ). I
typed the numbers into Excel and charted them at
http://damonrinard.com/images/rr_kyle.gif. The PU liner listed at the
bottom is a polyurethane tire liner (perhaps a Mr. Tuffy brand). It
approximately doubled the rolling resistance. Here's the text of Ray's
post:
================
Subj: Re: HBS: Rolling Resistance
Date: 97-03-14 13:27:31 EST
From: RayB...@aol.com
Sender: owner-hardcore-...@cyclery.com
Reply-to: hardcore-bic...@cyclery.com
To: hardcore-bic...@cyclery.com
john...@magna.com.au (John Stevenson) asked:
>Anyone have figures for RR versus other losses to hand?
And others have requested RR data also.
Dr. Chester Kyle has made measurements of Crr (Coefficient of rolling
resistance). These were measured at low speed based on the "roll-down"
method. He used a weighted cart with bike wheels. Because Crr does not
vary
much with weight or rolling speed, his measurements are useful despite
the
low speeds involved in his tests. I have copied some of his results
below.
The Crr values I copied are for a smooth surface, linoleum. He also
made
some measurements on an asphalt surface, which gave Crr values typically
1.1
to 1.2 times larger.
###Moderator: I'm trying to remember, did he actually vary the weight to
show
that the ratio is constant? Also, how did he know his wheels were
aligned.....?###
Note the large increase in rolling resistance caused by the PU tire
liner.
The stiff liner probably involves considerable scrubbing. Many people
have
reported flats caused by the ends and edges of PU tire liners, which
supports
the scrubbing speculation. Recently, stiff Kevlar tire liners have been
introduced. Almost no reliable data exists yet for these, but several
people
have reported weird, loud, howling noises from their tires when using
these.
This noise is fairly certain evidence of large RR losses, and chafing
damage
to tubes also seems likely.
Ray Bowman
ROLLING RESISTANCE MEASUREMENTS
made by Dr. Chester Kyle in the mid-1980s and reported in the June 1988
Issue
of Bicycling
Rightmost column gives the Crr in %. To obtain rolling resistance
(drag),
multiply weight of rider plus bike by Crr and divide by 100.
Except as noted, wired-on tires were fitted with butyl ultralight tubes;
tubulars with latex.
Actual tire widths, and the marked widths for the 700C rims, were not
given.
TUBULAR
Continental Olympic 18 mm 133 gm 0.19 %
(Fine File) 120 psi
Vittoria Cronometro 18 mm 189 gm 0.20 %
(Fine File) 120 psi
Clement (track silk) 18 mm 107 gm 0.16 %
(Smooth) 120 psi
Continental Sonderklasse 25 mm 165 gm 0.30 %
(?) 100 psi
Clement Criterium 25 mm 250 gm 0.32 %
(?) 100 psi
Clement Nuovo Seta Extra 25 mm ? 0.26 %
(?) 100 psi
WIRED-ON
Moulton-Wolber 17x1.25 in 254 gm 0.30 %
(Narrow Rib) 100 psi
Avocet FasGrip 30 700C 203 gm 0.29 %
(Smooth) 100 psi
Michelin Hi-Lite Comp 700C 213 gm 0.29 %
(Smooth) 100 psi
Specialized Turbo/R 700C 219 gm 0.26 %
(Smooth) 100 psi
Speciaized Turbo/SK4 700C ? 0.23 %
(Smooth) 100 psi
Specialized Turbo/S 700C 195 gm 0.258 %
(Fine File) 100 psi
(latex Tube)
0.252 %
(polyurethane tube) 0.288
%
(polyurethane tire liner) 0.540
%
--
Damon Rinard
Damon Rinard's Bicycle Tech Site:
http://www.damonrinard.com/
Andrew Duncan
> Some years back Dr. Kyle made rolling resistance measurements
> for quite a few tires
...
> He found that tire liners installed in narrow tires
> (typical road bike tires) essentially doubled their rolling
> resistance.
Which begs the question: how much will that affect, for example, a 40k
ride?
Andrew Duncan
adu...@cs.ucsb.edu
http://www.cs.ucsb.edu/~aduncan
Tom Compton
Run the numbers yourself using the calculator at
http://www.analyticcycling.com/DiffEqMotionFunctions_Page.html
using the average power input form.
Use a Time at End of something like 4000 seconds and a
Distance of 40000 meters. Double the rolling resistance from
one case to the next.
Tom Compton
www.analyticcycling.com
Andrew Duncan <adu...@cs.ucsb.edu> wrote in message
news:37B86280...@cs.ucsb.edu...
Mark Atanovich
James Connell <jc...@ipns.com> writes:
> bob, i use a tuffy in the back only on my commuter. it does increase
> rolling resistance, but it's acceleration that suffers most.
I have Mr. Tuffy's on both my commuter's wheels and acceleration
*really* suffers. Then again, it could have something to do with the
15 pounds of gear on my rack...
Steve Sloan
commuting I gave him the boot. He was causing more flats than he was
preventing. Most of them happen right where the tongues overlap. When I
hit something at a glancing blow, like when you swerve to avoid an
obsticle at night at almost the last minute, and it impacts the sidewall
of the tire I often got a pinch flat caused by the edge of the liner.
I am riding Conti (old style) Top Tourings 700x32. I have ridden them on
tours and commuted on them and after thousands of miles haven't gotten a
flat. (Knock on electrons.) On one tour I passed the same people fixing
flats on Michelin Axial Pros over and over. By the time you averaged out
the time they spent fixing flats on their skinny tired racing bikes we
averaged about the same time and I was in the saddle! I have great photos
of riding buddies fixing flats!
I love the Conti (old style) Top Tourings and since I dumped Tuffy I am
happier and wiser.
Steve Sloan
sl...@jmc.sjsu.edu
fr...@easyaces.com
liners seem much lighter and more supple than Mr Tuffy.
John F. Henderson on is3
> I used to think Mr. Tuffy was my friend. But after a couple of years of
> commuting I gave him the boot. He was causing more flats than he was
> preventing. Most of them happen right where the tongues overlap. When I
> hit something at a glancing blow, like when you swerve to avoid an
> obsticle at night at almost the last minute, and it impacts the sidewall
> of the tire I often got a pinch flat caused by the edge of the liner.
Hold the flame of a lighted match to one end of the Mr. Tuffy. The
plastic will begin to melt and smoke. Blow out the match, let the plastic
cool for a while, then blunt/soften the edges. Repeat with the other end.
When completely cooled, install. No flats caused by Mr. Tuffy in 3 years
of this treatment.
-John Henderson
Charles P. S. Gianotti
>Does anybody have any experience with Spin Skins? These kevlar-based
>liners seem much lighter and more supple than Mr Tuffy.
... until they dry out & the kevlar fibers cause punctures ... at least that's
what I've heard/read.
Clownie
far, no flats after a couple hundred miles, will probably switch to loaded
tubes when i change this rear tire (didn't bother with liner in front as I
almost never get flats there.
Brian
Steve Sloan
> plastic will begin to melt and smoke. Blow out the match, let the plastic
> cool for a while, then blunt/soften the edges. Repeat with the other end.
> When completely cooled, install. No flats caused by Mr. Tuffy in 3 years
> of this treatment.
>
Good idea! I never thought of this. But, since my Top Tourings have been
so flat resistant, since I have been recklessly enjoying the pleasures of
unprotected riding, since I've getting away with it, I think I'll continue
to leave my liners at home when I go out on the town.
Maybe I have just been lucky. But, I just think it feels better without
protection. Yes, that could all be in my head. I know that there is
probably so little nasty out there waiting to get me. Probably some
lonely night it will be my turn. There I will be, me and Blackburn stuck
pumping in the dark. Maybe it will even be raining.
Maybe then I will be wiser and start using protection again. Mister Tuffy
will again guard me from the evils of the road. If that happens I will at
least have my memories of these wild times, these days of living
dangerously.
Steve Sloan
sl...@jmc.sjsu.edu