Schwalbe lightweight balloon tubes

SCHWALBE SUPER LIGHTWEIGHT TYPE 19A BALLOON TUBE WITH BIG APPLE
LITESKINS
an acceleration advantage
by Andre Jute

To go with their Big Apple Liteskins, Schwalbe also makes a Super
Light tube in the correct size, type19A.

Between a pair of Liteskins and a pair of 19A tubes, the weight-
conscious cyclist can save several hundred grams. In steady state
motion the weight might not matter so much, but in acceleration its
disposition does: it is all taken from outside the rim, thus so much
less to accelerate, with the rim radius being the multiplying lever
arm.

Utility cyclists working mainly on the flat might not care; sporting
cyclists or even the putterers with hills on their rides will care
very much.

I don't have standard Big Apples and standard tubes to compare with,
but my Utopia Kranich, on which the 60mm Liteskins and lighweight
tubes are fitted is not noticeably harder to get moving or to
accelerate in the higher segments or to climb my daily hills than my
other bikes with 37mm Schwalbe Marathon Plus tyres (or Bontrager
equivalents) and standard tubes.

Nor do the lightweight tubes appear to be more puncturable than the
standard tubes though my use isn't extreme in that my roads are good
and clean; I also have only about 630km on the balloon tyres and
tubes. I would expect the Liteskin tyres to have the same puncture
protection as the standard Big Apples; my understanding is that the
difference is in the sidewall construction.

However, the lightweight tubes do definitely have a tiny downside.
Again, I'm not comparing them to the standard tubes in the Big Apple
sizes (I have some of those for spares but not used yet), I'm
comparing them to standard-weight tubes riding in Marathon Plus tyres.
The downside of the lighweight tubes is that they appear to lose air
more quickly than the standard tubes. That is probably to be expected.
How much it matters depends on how you use your bike; I don't think it
will matter much to anyone who doesn't use the bike in an absolutely
extreme manner.

Over a period of three to four weeks, which is my normal tyre-check
interval, Schwalbe's type 19A lightweight tubes, fitted to Big Apple
Liteskin tyres, inflated to 2 bar, lose almost 0.3 bar. This compares
to standard tubes (again, in a narrower size inside a a different type
and size of tyre) in the same use losing imperceptible amounts of air
over periods of 8 to 12 weeks.

In short, you can ride standard tubes unchecked in thornproof tyres
for three months without risk, on good clean roads anyhow, but the 19A
super lightweight balloon tubes need to be checked at least once a
month, probably every three weeks if you inflate them at the check
only to the ultra-low pressures that the widest balloons invite,
apparently still without danger of snakebite punctures.

Together with my bike and permanent on-bike gear I weigh quite the
quarter-ton, and I found 1.7 bar to be problem-free (I've been below
but found it unnecessary), but I would probably check that once a
week. Since I however appear to have stabilized at 2.0 bar front and
rear as comfortable enough and fast enough and very controllable
around corners, a check every three or four weeks will be good enough.

Even if you prefer the ultra-low inflation regime for your weight, a
check once a week doesn't seem too big a chore to me.

CONCLUSION: Schwalbe's super lightweight balloon tubes when teamed
with Liteskins do their business of faster acceleration without cost
in flats, maintenance or irritation.

Copyright © Andre Jute 2009
Free to use on non-profit netsites. Other use contact author. Visit
Jute on Bicycles at http://www.audio-talk.co.uk/fiultra/...20CYCLING.html