The wheels on this new, very high-performance touring bicycle are fairly typical of relatively lightweight wheels built for someone that weighs 135 pounds and is touring on pavement. The wheels have 32- and 28-hole (rear, front) rims that weigh 405 grams and are 19mm wide. The 700c tires are 25mm wide and weigh 215 grams. They are matched with 65-gram tubes. Spokes are 14/16 gauge, stainless double-butted. The wheels on this bike are exactly like the ones that were built for the old Trek 720.
Changing tubes and tires is simple, but changing rims and spokes
requires that new wheels be built, however it is something that I highly
recommend when much lighter wheels are consistent with rider weight and
riding conditions. In setting up used bicycles as great touring bikes,
having wheels built is by far the most expensive aspect of altering the
bike, but if it is possible financially, I'd highly encourage it. I thought that my friend could benefit significantly from much lighter-weight wheels and I
had new wheels built. I chose to reduce spokes from 36
in the front and rear wheels to 28 and 32, respectively, and the rims
were reduced from 510 grams to 405. Reducing the rapidly rotating
weight of wheel components has a great impact on increasing performance,
which contrasts widely with the reduction of very small amounts of
static weight, such as in reducing the weight of a derailleur or brake
levers, or by insignificantly lowering the weight of other components,
through replacement, which will not be noticed. Large changes in key
wheel components are revealed quite astoundingly.
The performance of wheels can be improved in all bikes. If I for
instance, at 190 pounds, were setting the Trek bike up for myself as an
expedition bicycle, I would still make alterations in the wheels and I
would very carefully select wheel components. I'd follow the Advanced
Touring Method in setting up the bicycle as an expedition bike. Knowing
that almost all of the time I would have little or no extra weight over
the front end of the bike, I'd reduce the number of spokes to 28 or 32
and I would also use a lighter and stronger rim. I know that all of the time I'd
have at least 20 pounds of gear over the rear wheel, so one thing that
I'd do in preparation for a long expedition would be to try to trim some
of my body weight to offset some or all of the additional weight that touring
gear, mounted over the rear wheel, adds. Therefore, I could easily use the existing rear
wheel with 36 spokes. To save some dollars I might avoid purchasing a new
rim, and the expense of having a wheel built (although I could easily do it myself).
I know from extensive experimentation that I could not ride widely on
dirt with narrow, very lightweight tires. 32mm tires are as narrow as I've gone in the past, but I would never, ever use
fat, knobby tires on an expedition bicycle as permanent tires either.
The 1.75” or 2” tires that weigh 500 to 800 grams, which I often see
cyclists using, would be ridiculously overweight on a finely tuned
expedition bicycle. A more appropriate choice would be to use a
lightweight knobby tire with a smooth, or slightly textured center tread
of a narrow, but not too narrow width. Such tires, with a width of
1.25” or 1.375”(32mm or 35mm) and weighing 320 to 375 grams is a much
more reasonable option. There are extraordinarily rare conditions
(surfaces too rocky, or soils too loose or sandy to allow proper wheel
flotation) in which wider tires are absolutely necessary for expedition
use. I'd research my trip before hand and if such conditions were to
exist, I'd plan my trip in accordance and most likely I'd start from
scratch using a bike, like a used mountain bike, with wider clearances
for tires. I would use wider tires if necessary, but I would always try
to use tires that are as lightweight as is practical. Finding a good
balance in tire design between between those that reduce effort, provide comfortable riding and that develop practical durability is desirable.
Whatever the options, and choices that are made, wheel performance is
a very important consideration in touring, even when setting bicycles up on a
short budget.