Tyres for tired randonneurs
Size matters
I'm going to start this by telling you what I'm not going
to talk about - tubulars. They have their advantages and advocates.
However, if you don't already have several pairs of tubular wheels and
aren't fully versed in their care and feeding, I would not recommend
using them in unsupported ultra rides. Your time and money would be
better spent experimenting with standard wire-on or clincher tyres.
Desirable Qualities
Let's look at what qualities a randonneur might want from their tyres.
Randonneurs ride long distances, so comfort should be a top priority.
Unnecessary inefficiencies should also be avoided as they will add up
over long distances, so efficiency is also of importance. No one enjoys
getting punctures, so we would like to minimise those too. Tyres that
are easy to get on and off can be a godsend at 3 A.M.
How can we achieve these goals? Size matters! Changing to fatter tyres
is one of the most cost effective changes you can make to improve the
comfort of your ride. The bigger air volume helps the ride, even when
pumped to the same pressure as a narrower tyre. The wider tyre also
decreases your chances of snakebite or pinch flats (and consequently,
the possibility of damaging your rims on rocks or potholes) and thus
gives you the option of lowering the air pressure and getting a more
comfortable ride yet.
Regarding punctures from sharp objects, there's not much that you can
except practising your road litter avoidance skills. Kevlar belted tyres,
i.e. those with a puncture resistant (not puncture proof!) layer of
kevlar under the tread, only help avoid slash type punctures, like from
glass, and do not help with punctures from sharp pointed objects like
thorns and flint. They also add significantly to rolling resistance
and, in my experience, lead to long-term reliability problems with the
tyre casing.
Don't fatter tyres add significantly to rolling resistance too? Haven't
we all been told that if we want to go really fast, that we should use
the skinniest possible tyres inflated to 150 psi? In the world of randonneuring,
where you are going to be carrying some amount of baggage and travelling
at an average speed well below that of the world hour record, the heavier
weight and rolling resistance are of negligible importance. For two
otherwise identical tyres inflated to the same pressure, the smaller
cross section (i.e. skinnier) one will actually deform more than the
larger cross section (i.e. fatter) one and have greater rolling resistance!
That's an oversimplification, but don't lose sleep over rolling resistance!
A few years ago, Pamela and I, on our tandem with 32 mm wide tyres,
joined forces with a cyclist on a 300 km brevet. Our new friend was
very proud of his new titanium bike with go-faster 19 mm tyres. However,
he was also more at the Bubba end of the cyclist scale than the Pantani
end, and after getting his fourth pinch flat of the day, we came to
the realisation we would get to our destination sooner if we kept moving
rather than stopping repeatedly to fix punctures.
There is one other contributing aspect to rolling resistance and that
is the type of tyre tread. Tyres with a patterned tread (i.e. most available
tyres) have measurably higher rolling resistance than smooth treaded
or slick ones (e.g. Avocets and Michelin Hi-Lites).
Easily fitting or removing a tyre depends on several variables. One
is whether the tyre has a traditional wire bead or a flexible kevlar
bead. The former tends to be easier to mount and dismount. The latter
are initially tighter and can stretch with time. Another factor in the
mounting/dismounting equation is the type of rim you use, with tyres
being easier to mount on rims that have a deeper well between the sidewalls,
allowing you more slack to lever over the sidewall. Yet another variable
is the type of rim tape that you use, with thinner ones allowing yet
more slack.
I've tried to avoid mentioning specific tyres until this point. They
are another one of these items where one person's pleasure is another's
poison. Biting the bullet, I've had really good luck with Avocet
smooth treaded tyres (I don't like referring to them as 'slick' tyres
because they grip very well) on both solo and tandem bikes. They are
almost identical across the range, from skinny to fat, in terms of casing
construction and tread thickness, therefore allowing you compare narrow
and wide tyres without other factors coming into play. They roll and
wear well and have durable sidewalls and, best of all, do not come in
fashionable colours, unlike most other tyres at the moment!
Tubes, Pumps and Accessories
There are several accessories that are worth carrying with you at
all times. Most crucial are spare inner tubes. Keep valve caps on them
when they are stored away in your saddlebag so that the valve end can't
puncture the tube - you do not want to find that your spare tube is
punctured at 3 A.M. in the pouring rain! Make sure that all your spare
tubes have long stem valves if you use deep section aero rims, or carry
a valve extender. Latex tubes are lighter than butyl, but tend to be
on the fragile side.
Those spare tubes won't be of much use to you if you don't have some
means of inflating them. CO2 cartridges have their advocates, but I
prefer pumps from an ecological and practical viewpoint. Size matters
here -bigger pumps really are better! A frame pump like a Zefal hpX
or that very impressive floor pump imitator, the Topeak
Morph, make inflating tyres to high pressures very easy compared to
their illegitimate mini-pump cousins. Don't forget to give them some
occasional attention and lubrication, making sure that the piston can
move easily.
Tyre boots are another useful item. These allow you to continue using
a tyre after it has sustained some damage, say a long cut, by going
between the tube and hole and thus protecting the tube. Useful materials
for doing this are Tyvek (the material used in Federal Express envelopes,
amongst many other applications), a small piece of an old tubular with
feathered edges or the old standby, a dollar bill.
A kevlar beaded, foldable spare tyre can take over where the tyre boot
ends, for example, if a tyre fails at the bead, a place that is difficult
to boot. If the tyres that you normally use are wire beaded, make sure
to practice mounting your spare somewhere nice and warm and when you're
not in a hurry. Then, just in case your neighbours don't already think
that you're completely crazy, you could practice changing it outside
in your driveway some night when it's cold and raining to replicate
'real' conditions!
Riders don't think a whole lot about rim tape until their existing
tape gives problems. Velox has given me trouble free service over the
years. It's very tough but also on the thick side, so could give tyre
mounting problems. It comes in several different widths, so make sure
to get the appropriate one for your rims. It also resists heat better
than any other rim tape that I am aware of, making it very suitable
for riding in mountainous terrain where heavy braking is required, resulting
in hot rims (especially the case on tandems).
Puncture repair kits come in basically two varieties, the traditional
vulcanising type typified by Rema and the newer adhesive patches, such
as made by Park. The latter are great for a quick roadside repair, but
aren't to be relied on permanently in my experience. If you rely on
the former, make sure that you have a new tube of glue before starting
on a long ride!
I hope that was more about tyres than you ever wanted to know. One
final piece of advice though: keep the rubber side down.
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