Vittoria Air-Liner Road Test
Contents
The Vittoria Air-Liner Road is an extremely light, re-usable, run-flat tire insert that solves some of the shortcomings of tubeless tires at no additional performance cost. Of course, we're always skeptical of products that solve many problems as there must be a trade-off somewhere. This time it seems different, as except for the 24 grams (size S) weight increase, most of the claims appear to be true.
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The first problem the Air-Liner Road solves is inflating tubeless tires, which can be a real problem with some tires and rim combinations. The Air-Liner solves this problem by making sure the beads are pre-seated and inflating the tire becomes extremely easy.
In case of a puncture, the Air-Liner keeps the beads locked into place and even allows you to run on a flat tire in emergency conditions. Although run-flat riding isn't recommended (and rolling resistance will sky-rocket), it'll give you the ability to let the tire sealant do its job and re-inflate the tire easily. If the puncture is too big for the sealant to work, you'll at least be able to get home at a modest speed.
The special thing about the Air-Liner Road is that when the tire is inflated, the Air-Liner shrinks, and it isn't in contact with the tire anymore. There should be no adverse effect on rolling resistance when there is no contact between the tire and Air-Liner. See the animation below, which we found on Vittoria's website, clearly showing how it works. For more information about the Air-Liner Road we suggest to visit Vittoria's Air-Liner Road page that contains a lot more pictures, videos, and recommendations.
This test was requested, supported, and voted for by our Pro Members. We've tested the Air-Liner Road with 3 road bike tires: Vittoria Corsa Speed G+ 2.0 TLR, Vittoria Corsa G+ 2.0 TLR, and the Continental Grand Prix 5000 S TR. We've averaged the data from those 3 tires and made that available for free for anyone. There were some slight differences between the individual tires but nothing that could affect the outcome of this test.
Pro Members can open the individual tire data and dig into the results further.
Installation and Removal
The Air-Liner Road comes in a nice bag together with a special tubeless valve and a short manual. The special tubeless valve should be used as it has some extra holes that make sure you can easily add sealant.
Vittoria recommends using their sealant or any other sealant that does not contain ammonia, which might damage the Air-Liner.
The Air-Liner Road currently is available in 3 sizes: S, M, and L. See below for Vittoria's chart with their recommendations on which size to use based on tire size and rim width.
Installation and removal of the Air-Liner Road can be quite difficult but can vary greatly depending on the exact rim width and tire size combination. Installation of the Air-Liner is easier than removing it, but we've found a trick that makes it a bit easier and isn't found in the Vittoria manual (see below).
Vittoria also offers a toolkit with some special tools that make removing the tire a bit easier. This toolkit helps make your life easier, but whether you need it depends on your exact tire and rim combination. Below is the size chart found on Vittoria's website with their recommendations based on tire size and rim width.
We've tried both an 18 mm and 22 mm rim with 25 mm tires, and our recommendation on whether you need the toolkit is:
When you're in the higher end of the size chart (size S, 25 or 26 mm tire, 20 or 21 mm rim), you probably don't need the toolkit. When you're in the middle (size S, 25 or 26 mm tire, 18-19 mm rim), you probably need the toolkit. When you're at the lower end of the chart (size S, 23 or 24 mm tire, 15 - 17 mm rim), we're quite sure you also don't need the toolkit as it won't help to get the tire off; it can only be removed by cutting the tire off with wire cutters.
The advantage of a tighter fit will be more pressure on the beads when run flat, which is better, but the right size is a trade-off between functionality and ease of installation/removal. If you don't mind cutting the tire off, get it as tight as you can.
Our tip for easier installation and removal is to pre-seat the beads when installing and keep one bead seated for removal (more below). This gives you about 3 mm of extra room within the rim and will help significantly as more room = easier installation.
Installation tip: This one isn't as important as the removal tip, but when you have a hard time getting it on, it definitely helps. Before mounting the Air-Liner, install the tire without the Air-Liner and inflate it so both beads get seated. Then release the air and gently unseat one bead, and make sure the other bead stays seated. Now get some tire levers and get the bead off the rim and install the Air-Liner.
Removal tip: ALWAYS use this one as it always helps to make removal easier. When you've deflated the tire, do not unseat both beads but make sure 1 bead stays seated. When you only unseat 1 bead, there will be more room left over for the Air-Liner and getting the other bead over the rim edge will be much easier.
Test Set Up and Conditions
All rolling resistance tests were performed with our standard test protocol. This is the same protocol used for nearly all of the rolling resistance data found on this website.
We've used the Air-Liner Road in the "S" size and a 22 mm rim for this test's final data, which technically is 1 mm larger than Vittoria's recommendation.
We also did some tests with an 18 mm rim, and the only difference can be found in the 0 psi / 0 bar test results where the 18 mm rim rolls a bit faster because it fills the tire/rim better when run flat.
If you don't mind the extremely hard removal, a tighter fitting Air-Liner always seems better.
Rolling Resistance Test Conditions
- Speed of 8 m/s - 28.8 km/h - 18 mph
- Total wheel load of 42.5 kg / 94 lbs
- 21.8 mm internal width rim
- 20 ml sealant
- Temperature between 21.5-22.5 °C / 71-72 °F
- Diamond plate drum surface
- 77 cm drum diameter
Test Results - Air-Liner Road Average of 3 Tires
We've tested the Vittoria Air-Liner Road S with the following tires
- Vittoria Corsa Speed G+ 2.0 25-622
- Vittoria Corsa G+ 2.0 TLR 25-622
- Continental Grand Prix 5000 S TR
To keep the test results easy to understand, we've averaged the test results of the 3 different tires:
| No Air-Liner | Air-Liner Road S | |
|---|---|---|
| Air Pressure | Watts | Watts |
| 100 psi / 6.9 bars | 9.8 | 9.9 |
| 80 psi / 5.5 bars | 10.9 | 10.9 |
| 60 psi / 4.1 bars | 12.6 | 12.6 |
| 40 psi / 2.8 bars | 16.6 | 16.6 |
| 20 psi / 1.4 bars | Fail | 28.1 |
| 0 psi / 0 bars | Fail | 84.4 |
| Average of 3 road bike tires (Speed: 29 kmh / 18 mph, Load: 42.5 kg / 417 N) | ||
The averaged test results clearly show there is no rolling resistance penalty when using the Air-Liner Road. We tried to run the tests down to 20 psi / 1.4 bars without the Air-Liner, but all tires failed because air was lost through the beads. With the Air-Liner, there was still 20 psi / 1.4 bars of pressure after completing the tests.
Rolling resistance at 20 psi / 1.4 bars still looks quite good, although it looked like the wheel was already running on the rim edges. It definitely was running on the rim edges at zero pressure as the Air-Liner isn't stiff enough to support the load. At zero air pressure, rolling resistance sky-rockets to about 85 watts for a single tire.
Although we did test at zero air pressure, we're not sure if tubeless road bike tires filled with sealant will ever drop to zero. Of course, it will if the cut is big enough, but it might very well stop somewhere between 20 and 60 psi for many other punctures as the sealing capability of tubeless sealant depends a lot on the air pressure.
Test Results - Individual Rolling Resistance Data (Pro Members)
The next section is only accessible by our highly valued Pro Members. This section includes all test data of the individual tires used for the Air-Liner Road tests: Vittoria Corsa Speed G+ 2.0 TLR, Vittoria Corsa G+ 2.0 TLR, and the Continental Grand Prix 5000 S TR.
Conclusion
Our main conclusion is that using the Vittoria Air-Liner Road does not harm rolling resistance. Rolling resistance is exactly the same at all air pressures, even down to 40 psi / 2.8 bars which is a pressure that's already way too low for a 25 mm road bike tire.
With the Air-Liner Road, we could complete the tests at 20 psi / 1.4 bars with full pressure remaining after the tests. Without the Air-Liner, all tires failed the 20 psi / 1.4 bars tests as there was air loss through the beads. Even though the tire only runs forward on the rolling resistance machine, this indicates the Air-Liner helps keep the beads seated, which is a considerable performance and safety advantage.
We do see a potential issue when the air pressure is between 40 psi / 2.8 bars and 60 psi / 4.1 bars. At those air pressures, the Air-Liner will have shrunk to quite a small size, and we're unsure if it can support the bead when going through turns at high loads. Just be careful and know the Air-Liner can't protect you under all circumstances.
Although you can technically run on flat tires with the Air-Liner, be aware that you'll be running on the rim edges as the Air-Liner foam isn't stiff enough to support the load. It might become costly if you have some nice expensive wheels as we're not sure the rim edges of expensive wheels can survive that.
The ability to always reinflate your tires is probably the strongest point of the Air-Liner Road. If you have enough sealant in your tires, you probably can recover from quite big punctures as long as you can reinflate the tire and slowly build up the pressure. Carrying a spare tube will be useless as we're quite sure you can't remove the Air-Liner at the side of the road.
We're curious about real-life experiences with the Air-Liner Road. Have you used these? Feel free to leave a comment.