Going Tubeless -- What's the deal?
You've heard the hype about tubeless tires, and you're wondering if they're
really worth while. Well, for most riders, the answer is probably
"no." So, who SHOULD go tubeless?
||Tubeless is an advantage to hard-core riders who want
maximal responsiveness and control, while avoiding pinch-flats in
difficult terrain. "Going tubeless" is not worthwhile if you're basically a
gutter-bunny who occasionally ventures onto smooth dirt trails.
An example of terrain that screams
"Tubeless." Rough, demanding, and tricky, with sharp edges that
are ready to pinch-flat your tube.
Tubeless riding has a good side, and a bad side. If you're going
from standard rims to a genuine UST tubeless system, it's a big step, and a huge
cost. For your style of biking, consider carefully whether it's right for you
before taking the leap. You can go tubeless two ways: (1) with an official UST rim and
UST tire, or (2) with a conversion kit that lets you use your current rims and a
standard tire. Each has its own set of hassles. Here are some quick headlines about the good and bad of tubeless:
- Lower inflation pressures
- Better bump absorption
- Better control
- Reduced rotating weight
- No pinch-flats
- Costs more
- Messy sealant
- Backup tube required
- Power inflator required
||Good: No pinch-flats.
Pinch-flats occur when your rim pinches the inner tube against an edge,
such as a rocky ledge or root. If there's no inner tube, you can't get a
pinch flat! You can, however, cut a hole in the tire. (You're more likely to cut a hole through the tire
casing while tubeless than you are with a tubed system, because you don't
have an inner tube to add cushion between the rim and tire. Use a big tire,
such as a 2.1, and keep your pressure above 30 psi.)
|Good: Better bump absorption and
better control. When there's no inner tube pushing
against the tire casing, it will deform more easily when it rolls over a
rock. That means sharp bumps become softer bumps. Tiny bumps such as small
rocks don't cause as much vibration and shaking. The end result: a
smoother ride, better response, better control.
||Good: Reduced rotating weight.
A standard UST tubeless tire is heavier than the corresponding
non-tubeless version. But once you allow for the heft of the inner tube, the
weight is usually a bit less. (If you add sealant, your weight is about
the same, or even slightly more.)
Many tubeless riders actually use a standard tire on UST rims with tire sealant. This can shed
grams per wheel. This reduction of "rotating weight" makes the
bike "zippier." It accelerates better, corners faster, brakes
If you're converting a standard rim to tubeless, using rim liner, sealant,
and a standard tire, the wheel's rotating weight is less than with a standard
inner tube by about 50 grams.
|Good: Lower inflation pressures
possible. In many circumstances (rough rock, snow, mud,
slippery or rough roots) a lower inflation pressure gives you better
control and a smoother ride. With a tube, pinch-flats occur as you try to
find that ideal low-pressure ride. When you're tubeless, you can drop the
pressure lower than you'd dare with a tubed system.
But on the other hand...
Initial cost: To go traditional tubeless, you need to buy
special UST rims, which aren't cheap. You'll spend
between $400 and $1000 to upgrade both wheels, depending on the quality of
the rims you buy. A UST tubeless tire costs about
twice as much as the same model in the standard variety.
|The cheapest way to go tubeless is with a conversion kit. You add a rim
liner to your standard rims, fill a standard tire with sealant, and you're
there. A kit from Stan's No-Tubes will cost you about $55 after shipping.
Sealant: You'll have to buy sealant periodically. But on the other hand, you won't
be buying as many inner tubes.
Tires: If you're using tire sealant, your tires won't last as
long -- especially true if you're using standard tires with sealant. The
sealant eventually softens the rubber. After several months, you may get a
puncture or cut that won't seal. And when you try to patch it, the rubber
rubs right off the cords inside of the tire, so the patch won't hold. You
may also have sudden sidewall blowout as the tire ages. Add this problem
to the increased likelihood of cutting your tire on a root or rock
(because there's no tube to offer shock absorption between tire and rim),
and you're going to be buying more tires.
CO2: To these expenses, add cartridges for your power
inflator. If you buy an inflator that uses cartridges with non-threaded
necks (standard BB-gun CO2 cartridges), it's cheaper, but still a couple
of bucks each time.
|Bad: Messy sealant.
While you can run a UST tubeless without sealant, almost everybody uses
sealer. The No-Tubes conversion requires it. The sealant makes
changing a tire relatively painful. And where does that sealant go when
you DO cut your tire on that broken glass bottle? It sprays on your
expensive bike jersey,
into your derailleur, all over your cables. When sealant gets into critical
parts, you have a difficult cleanup problem -- when it's dry, it won't
||Bad: Backup required.
You can repair small punctures in a dry tubeless tire with superglue. You
can repair sealant-filled tires on the trail by patching it internally.
But tubeless riders who don't pack a emergency inner tube (or two!) will, sooner or
later, face a long hike. On the trail, you'll need a patch kit, spare
tube, and maybe even a little bottle of sealant.
|Bad: Power inflator required.
To seal a tubeless tire against the rim, you need a sudden burst of air pressure.
Your mini-pump just can't do that. Most tubeless owners find they can't do
it with their floor pump, either. That means
a compressed-air source. So you need a compressed-air cylinder in your
garage, or a gas station with real compressed air -- not just an
insert-a-quarter type electric pump -- or, you burn up a CO2 cartridge
every time you mount a tire. (That's why a higher percentage of guys at
bike shops ride tubeless. They have a compressed-air hose ready and
|If you stick a rim liner in your UST rim, you may be able
to get the tire to seal with a standard floor pump. It will NEVER work
with a mini-pump. But whether you use a tire liner or not, for on-trail
inflation, you'll need a CO2-powered
inflator. Power-inflators are great little gadgets. But many riders don't
want to spend a few bucks on a CO2 cartridge every time they get a flat
tire. (Yes, that's right. You can spend up to $4 for a CO2 cartridge
that's good for ONE tire inflation.)
How does a "conversion kit" work?
||You can convert a standard rim to run tubeless by adding a
rubber rim liner. The rim liner has a valve that sticks out through your
valve hole just like an inner tube. The rubber strip provides an airtight
(hopefully) seal against the rim, and against the bead of the tire. (You
could experiment with making your own rim strip by cutting up a small --
child's size, 20 or 24-inch -- inner tube. This won't work on many deeper
rims, and it's harder to cut a straight strip of tube than you might
|You can use regular, non-tubeless tires with the conversion
kit. (You can also use the tire liner in the conversion kit on a UST tubeless rim, which
makes it easier to seal a lightweight standard tire on your tubeless rim.) Not all
tires, and not all rims, will hold in place when inflated without a tube.
At higher pressures (40 to 50 psi) the tire may blow off the rim. If you
have a chain-store bike with $4 tires, don't plan on converting those
wheels to tubeless.
||To provide a seal between the rubber rim liner and the
tire's bead, a sealant is required. Although it looks like it adds lots of
weight, it's only about 60 grams -- about 1/3 the weight of a lightweight
inner tube. A removable valve core lets you squirt sealant directly
through the valve stem without removing the tire.
For more information on installing and repairing
tubeless systems, go to: