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TIRES! |
Our "Tires!" page has been and is being edited to
reflect the fewer choices and changes in availability.
The article reflects my personal experience and that of
other teams having a variety of needs. Expect to learn about ride quality,
sidewall durability, tread life, handling, ability to withstand heavy loads,
and the negative effects of gravel and or rough pavement. Discussions about
tread compounds, threads per inch and the like will be reserved for the bicycle
science type lists.
Several factors should be considered when selecting a tire
for your tandem. Since no one tire will "DO ALL" and
"BE ALL", sacrifice is often there to a degree. For example one cannot expect to ride on a
narrow light fast road tire with a team weight of 450 - 500 pounds, at least not
very far. Other considerations in tire selection include rough pavement or the
need to load the bike for touring. Using the wrong tire for the job will result
in great frustration and it won't be a fun nor safe day.
The general consensus is that tread on bicycle road tires
has absolutely no useful purpose on wet or dry pavement as it is impossible to
hydroplane a bicycle tire unless you exceed 120 mph. The more rubber you have
in contact with the road the greater the traction. Tread is useful when on a
loose or soft surface, conditions generally not encountered on the road. Tread
on road tires decreases traction, increases rolling resistance, adds vibration,
and creates noise. People are so ingrained to tires having tread from their
automobile knowledge that its existence on bicycle road tires seems to
be deeply rooted in marketing efforts.
My experience includes the use of several tires from various
manufacturers, some currently in production and others that are now history.
The tire recommendations and thoughts are based on current availability and
first hand knowledge and should not be considered to be all inclusive as other
options may exist to which I am not privy nor knowledgeable.
Tire Width, The
Great Dilemma
Most of us want to go fast and do so efficiently making it
natural to contemplate narrow, light and expensive tires. Selecting the proper
tire width for the weight and task is probably the most misunderstood element
in the determination process. I made a posting to the T@H list back in May of
2000 where I alluded to common misconceptions about running narrow
"fast" tires as you will read below.
Original Post: Time to put another set of tires on the tandem ('98 C'Dale RT1000). Been running Conti. GP 3000 700 x 28's. Switching to same tire but in a 25c width.Input from others running 25c tires? too narrow? wear characteristics?Been getting 1000-1500 miles from 28c, rotating every 500 miles, frontTo rear and changing direction of rotation. Subject: Re: [T@H] Tire sizeDate: Thu, 11 May 2000 15:15:27 -0500 Robert, We have gone through a couple sets of Conti GP 3000 with the first pairinstalled for the 750 mile Paris Brest Paris event last August.Fortunately, these tires improved the comfort of the ride as compared tothe old Super Sport 100's, something we strongly desired for an eventthis long and the French road texture. We have a couple of stories about PBP '95 and '99 posted on our website.
We barely made it to 2000 mi on the rear tire before hitting the cordsand 3000 miles on the front. They seem to wear about 30% faster thanthe regular Grand Prix model. 25mm tires can be a bit narrow and likely have a higher rollingresistance than the 28mm width unless one is able to run them atextremely high pressure. It seems I recall an optimal tire pressureinflation chart that showed I would need to run something like 145 psiwith 25mm tires versus 120 psi with the 28mm width. The narrow tires may look fast, feel fast, sound fast, but I am not sosure they are. Mark and Sue Johnson~~~~Precision Tandems~~~~
The Continental Grand Prix 3000 tire referenced above is no longer
available.
Below is the chart referred to in the above post. You can see that
extrapolation is necessary for all but the lightest teams. The chart refers to
total weight of the ready to ride team and loaded bicycle. Before you look at the chart, be aware that
there are weight differentials in many cases with different tandem teams as
outlined in the following examples and formula applications.
To calculate the weight for a given tire or wheel on a multi seat
bicycle, consider the following formula with its basics taken from a post on
T&H by Mike Breaux on 04/01/04:
Front weight = [(captain weight x (rear
compartment + chainstay)) + (stoker weight x chainstay)] / wheelbase or more
simply total weight - rear weight
Condition one
Captain 150#'s & Stoker 150#'s
Rear Weight = [(150 x 24) + (150 x (24+27))] / 69 = 163#'s
Front Weight = [(150 x (27+18)) + (150 x 18)] / 69 = 137#'s
So on an evenly weighed team, the rear wheel holds more weight / more pressure.
Condition two
Captain 170#'s & Stoker 120#'s
Rear Weight = [(170 x 24) + (120 x (24+27))] / 69 = 143#'s
Front Weight = [(170 x (27+18)) + (120 x 18)] / 69 = 147#'s
In the above example, the same pressure would be used.
Condition three
Captain 170#'s & Stoker 50#'s
Rear Weight = [(170 x 24) + (50 x (24+27))] / 69 = 96#'s
Front Weight = [(170 x (27+18)) + (50 x 18)] / 69 = 124#'s
So with a lightweight stokid, the front holds more weight than the rear and it
makes sense to adjust the tire pressure accordingly.
Condition four
Triplet Weights 170#'s, 45#'s, 50#'s & front 24", middle
27", rear 27" and chain stay 18"
Rear = [(170 x 24) + (45 x (24+27)) + (50 x (24+27+27)] / 96 = 107#'s
Front = [(170 x (27+27+18)) + (45 x (27+18)) + (50 x 18)] / 96 = 158#'s

Click on the image to enlarge
Questions to ask yourself when selecting a tire
A person's mindset is also a factor in deciding what tire is best suited
for the team. The questions below should help sort through your concerns.
1) Are you into fast sport or competitive riding?
2) What is your team weight? ..under 275? ..over 350?
3) Would you prefer durability (longer wear) at the expense of
added weight and increased rolling resistance? Gram counters and competitive or
fast sport riders will invariably say no.
4) Are your roads excellent, good (occasional problem but can
avoid the bad spots), or poor (unexpected hits, too many to miss)?
5) Are you a careful captain and take it easy over railroad tracks
and rough spots or do you hammer through everything to prevent loss of speed?
For simplicity, please allow me to make some generalizations for
the purpose of categorizing teams and tire recommendations. Categorizations
will not fit all teams across the board but at least some thought should be
stimulated!
A Team = Go fast hammerhead racer types and wannabes that count
grams, willing to spend money to save weight, interested in greatest efficiency
and not concerned about shortened tread life as a result. These teams are
usually very fit, ride a large number of miles, participate in competition or
do fast sport riding. Team weight is often near 300 pounds or less.
B Team = Possibly new to tandems, getting in better shape, weight
is dropping, not competitive all the time but may be with the right crowd but
does not necessarily seek it out in order to have a "good" ride. These teams will sometimes stop and smell
the roses. Longevity and durability and
reasonable performance from a tire is expected by this team and they do not
mind spending a little extra for a quality tire. These teams often enjoy and ride fine equipment. Team weight varies greatly but is often
between 300 and 350 pounds.
C Team = Into smelling the roses, prefer longevity and durability.
Not interested in average speed or saving a few grams. Does not mind being
passed. May prefer a more expensive quality tire or something quite basic. Working on long term goals of exercise,
possibly weight loss but not always, and improved health.
TIRE RECOMMENDATIONS
Please note that all tires discussed are assumed to be 700C unless
otherwise noted.
"A" TEAMS under 300 Pounds:
Consider a 25 or 28 mm width tire with either a Kevlar or wire
bead. Both widths are available in the
tires discussed below. The Kevlar bead
permits folding for ease of carrying a spare and it also saves weight. The steel bead may be a better choice for
those that ride in conditions where long term braking generates rim heat.
Folding Tires:
Our favorite folders are produced by Continental. The Grand Prix 4-Season comes in 25mm and 28mm widths, is
reasonably light, corners well, has excellent tread life, and a comfortable
ride.
Light teams that count grams seeking the winning edge should
consider the very fast Grand Prix 4000.
Expect to shave 70 grams by comparison with a 25mm set, the maximum
width available in this model.
Wire Bead Tires:
Our absolute favorite is the time tested Continental GatorSkin. Having personally ridden these tires for
nearly a decade, I can report zero sidewall failures nor S-bends in the
casing. Longevity, handling
characteristics and ride comfort are good with this tire but reliability is the
main feature that causes me to continue to use these particularly on our
triplet and quad given the very precious cargo! These tires are full size meaning the width numbers are accurate
and sometimes conservative. A 28mm tire
may measure 29mm once inflated a number of times which may lead to clearance
problems with older pre 2006 Alpha Q carbon forks. Lightweight teams would likely opt for the 25mm width if the
GatorSkin is the tire of choice since they are 'full' size.
NEW for 2011 is the Continental Gator Hardshell, a beefed up and
70g heavier version of the Gatorskin.
For a slight decrease in ride quality, longer tread life, and maximum
durability, you may find this to be your most practical and favorite training
tire. It would also be a good choice
for the rear tire given the rapid wear that takes place on a tandem.
A narrow rim is preferred for 25 mm tires such as the Shimano
Sweet 16, Spinergy, Topolino, Rolf Prima Vigor, and Bontrager Tandem
Wheels. Other narrow rims would be the
Velocity Deep V, Velocity Fusion, or the Velocity Aerohead rims. Use of a narrow 25 mm tire on a fairly wide
rim, common to many modern tandems such as the Velocity Dyad or Chukker models,
will unnecessarily expose the sidewall to road debris and the lowered profile
increases the propensity for pinch flats.
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"A" TEAMS Up To 350 Pounds:
A 28 mm width tire is recommended with either a Kevlar or wire
bead.
The foldable Continental tire to consider in a 28mm width is the Grand
Prix 4-Season with its Dura Skin sidewall protection.
The wire bead Continental tire to consider is the GatorSkin. The GatorSkin provides extra sidewall
protection and for a longer wearing tread go with the heavier less performance
oriented Hardshell model.
A Team summary: Use the folding Continental Grand Prix 4-Season if you
have the extra money and don't mind the cost, want the ultimate in performance,
and increased ride quality or comfort.
I have personally ridden the GatorSkins for nearly a decade and
have been very pleased with them. We usually get 2000-2400 miles out of a rear
tire before cords are exposed while running 120 psi with a team weight of 295
pounds. Teams that climb a great deal
or those with greater weight should expect fewer miles. Ride quality of the
GatorSkin is excellent and tread wear good with excellent sidewall life as I
have had zero failures to date. New
for 2011 is the Gator Hardshell model.
It is a heavier tire with thicker rubber, will be slower and ride
slightly harsher than its cousin, the Gatorskin. That said to help balance the wear between the front and rear,
the Hardshell would be a good choice for the rear tire.
The Continental tires discussed here are basically slick (as
desired) as they have very little tread with some siping as shown in the pics
above.
"B" TEAMS 300-350
Pounds:
Consider either the Continental GatorSkin or Gator Hardshell 28 mm
width tires for low rolling resistance and good performance. You will feel
confident running these tires if you sometimes enjoy good solid or somewhat
aggressive cornering. The characteristics and expected life of the Continental
tires are discussed under A Teams above.
The Continental 28mm width GatorSkin or the Gator Hardshell are
our favorites for this team weight. We
have personally used the Gator Hardshell on our quad at 140 psi, not to be
construed as a recommendation. Our quad and its riders recently tipped
the truck scale at 640 pounds!
"C" TEAMS Over 350 Pounds:
Jumbo teams and those on triplets or quads are advised to remove
their tires every 700 miles and check the bead tape since with heavier loads
the rim can actually wear through it causing a cut to form that will lead to a sidewall failure and
blowout. I personally replace both
tires after 700 miles regardless when used on our triplet or quad.
That said, my favorite tire for teams in this weight range is the
28mm Continental Gator Hardshell. We
have used these tires on triplets, quads and quints at 140 psi (not to be
construed as a recommended pressure) and find the sidewall wear at the rim
junction is far less than that of other tires.
The 32mm width GatorSkin tire would be my first choice for this team
weight should there be sufficient frame and fork clearance for the tire.
For 26" wheels, often used with Jumbo teams, triplets, quads
and even longer bikes, consider the 1.5" Kenda Tandem Tire. It features a generous width capable of
gravel stints, displays excellent wear properties, and has a high pressure
rating of up to 100 psi, something fairly unusual for a nice wide tire!
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Kenda Tandem Tire 26",
1.5" @ 100 psi! |
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Continental GatorSkin |
[
Home ] [ 1st Visit ] [ Tandem Display ]
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