Tuesday, November 2, 2010

Tubeless: an update

Since the beginning of this year I have been riding tubeless tires on my road bike. I was very enthusiastic about these as I had a wonderful experience on my mountain bike, so I fully expected my road experience to match that. To a large extent it did. Here are my findings.

All tubeless tires on the US market are made by Hutchinson. I have tested both the Fusion and the Atom. I also tested the Specialized S Works Turbo, which are made by Hutchison as well.

Here is the good: I stick to my original point that tubeless ride as well as any other tire. I have since had ample opportunity to test this concept on others and I am convinced riders can't tell the difference. What I do know is that people are very good at detecting small differences in tire pressure and even inexperienced cyclists can detect a 5 psi difference. If riders do sense a difference in how tubeless handle it is usually due to pressure differences. Also make sure to do a blinded test.

This situation reminds me of a rigorous review of hifi speakers I once saw. It turns out nearly all the perceived differences between high end speakers were due to differences in loudness. Once researchers corrected for loudness, none of the experienced judges could tell the difference between the sets in a blinded study.

I also know tubeless prevent flats due to potholes. Many times I have hit a pothole without any problem. Most of these hits would have resulted in snakebites using clinchers. Once on a fast group ride, I hit a pothole so hard that it dented the rim but I did not notice until afterwards: no flats!
It damaged the rim, but no flat!

You don't need sealant. I never use sealant and I have never had a problem. You also don't need a special pump. You can pump tubeless tires with a handheld pump, provided you have a large volume pump (the little carbon pumps don't work) and provided you pump fast initially. The key is to pump 10-15 strokes really fast until the tire seals. The air will leak out and you may be tempted to stop, but do not, keep pumping and the tire will seal.

The not-so good: Tubeless tires are harder to mount, especially the first time around. Road tires are not much better than mountain bike tires in this respect. Good technique -using the palm of your hands instead of your fingers- helps but it is still a whole lot harder than mounting a clincher.

Tubeless do not prevent all flats. You can still get flats due to piercing (California has some roadside plants that have very sharp long needles) and cuts. With my mountain bike I very rarely get flats, but that is not true on the road.

When you do get a flat, tubeless are more of a hassle (but see below for my new fix). There are some products available to help you but all have drawbacks.
To fix a flat use one of these.
Vittoria Pit Stop (and similar products) is the easiest to use, but my experience so far has been less favorable. Although it is a pressurized can and it will fix a flat and pump the tire at the same time (without the need to remove the wheel), I found it only works for the tiniest of holes and then again only temporarily. But it will get you home even when home is a few hours away. Unfortunately, it is expensive and it can only be used once. I would keep it for a road race or the bike leg of an ironman. Fixing a flat this way is very fast: just remove the offending object, apply the bottle to the valve and off you go. It is fast enough for you to be able to catch back on in a race. But be aware that it may not last.

Stan's sealant comes in a small container that is easy to carry, but you need to put it inside the tire and you  need a pump afterwards. Many people use it as a preventive sealant before they mount the tire and that is its recommended use, but I found that to be unnecessary. Furthermore, if you do fill the tire with preventive liquid of any kind, it will affect your handling and people will notice the difference compared to a clincher or tubular.

Slime comes in larger packages and it is more viscous than Stan's sealant. The main advantage of Slime is that it can fix larger holes and cuts. Both Slime and Stan's are good for many applications and both can seal a tire more or less permanently (or at least until it needs to be replaced for other reasons).

For a really large cut you will need a tire boot (or dollar bill;) and a tube, although I have witnessed cases that were beyond repair from the get-go.

I recommend taking Stan's or a small bottle of Slime on training rides. There is a very easy permanent fix that I have not seen advertised anywhere. You don't even need to remove the wheel from the bike or the tire from the rim!  But you do need a large volume pump and bike gloves. Here is how it works:

Just locate the hole or cut and remove any offending material. Rotate the tire so the hole is on the bottom. Using one tire lever lift the tire away from the rim. You can do this higher up on the wheel. Depending on how skillful you are you may or may not have to remove a short section of the tire from the rim. If you are careful all you have to do is move the tire away from the rim in one area.

Now pour in some Slime or Stan's. Just a little bit. Make sure the hole is on the bottom so the sealant runs down and covers it. Now remove the lever(s) or reposition the tire (here is where the bike gloves come in handy-they protect your palms). Pump the tire. This should seal the hole and pretty much use up all the sealant you poured in too -so there is no liquid sloshing around afterwards. Done!  

I have used this method several times now and it works like a charm.

Tomorrow more on Belgium. Stay tuned.


Brendon G said...

Great info, I've been thinking of using tubeless for racing in Belgium, how do you think it would work on the cobbles?

I've always thought that some Stans in a road tire would mean a nearly invincible tire, but you say that the liquid sloshing around is noticeable?

Frank Eeckman said...

I think it would work great on cobbles but I haven't tried. I rented a bike when I went to Belgium last summer.

When you put in a lot of liquid in, the tire does feel different -maybe I shouldn't have said "sloshing around" but it does feel different in my opinion (maybe I need to do a blind test??)

I am not sure about invincible because when you do get a sharp deep puncture (like a plant needle or a staple), the thing often stays in the tire and you have to stop to remove it or it won't seal well.

What I also noticed is that sometimes what appears to be a good seal can come loose a few days later. I had this happen once. Then I had to reapply slime but after that it was fine.