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My bike is this one: https://www.cube.eu/de-en/cube-aim-race-black-n-azure/601400

Overall, I'm very happy with the bike to be honest. The tires are Schwalbe tires on the Cube Aim Race bike, which is a cyclocross (at least I think it is, could be a regular MTB) bike.

I'm asking specifically if the thickness (width) of this particular tire brand (Schwalbe) makes difference speed-wise, but I guess the brand of the tire itself doesn't make much difference in this sense.

I am talking of course about the speed of the bike on flat road.

enter image description here
from https://www.cube.eu/de-en/cube-aim-race-black-n-azure/601400

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    "It is complicated" - really the design factors, followed by quality of the tire will make a bigger difference than the width of the tire. All else equal, there is a sweat spot for width where narrow is slower.
    – mattnz
    Aug 1, 2023 at 7:23
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    Mod Note: The OP edited the question to clarify the type of bike, and the type of surfaces. I have subsequently deleted the argumentative chat messages.
    – Gary.Ray
    Aug 1, 2023 at 23:53
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    I guess it counts as "function radical structure radical cyclocross bike", but it would make the OP's life easier to accept that it's a cross country MTB and there's nothing "of course" about riding one only on flat roads
    – ojs
    Aug 2, 2023 at 6:01
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    @ojs Insisting on the classification is a bit pointless to my opinion, as there might be regional and temporal differences as well, and it's sometimes very confusing. In Europe front-suspended hybrids are sometimes called "cross bikes", with cyclocross being the rugged road/race bike — and the Aim is probably for the "cross" market, not the XC one. But I recon that the OP's instance on strictly answering the question rather than providing the best answer for their problem is a bit off-putting, because it's clear from the question that there are some concepts that are still blurry for the OP.
    – Rеnаud
    Aug 2, 2023 at 7:25
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    @Gary.Ray Unfortunately the 'clarification' is somewhat inaccurate. The question probably needs rewording to focus on the qualities of the tyre and the intended use case rather than the bike. Something like "If using a high volume XC tyre for road riding would a narrower tyre be faster". The answer is still very much "it depends" and we have some great answers to that question already. Refocussing the question on what matters would help to remove the background noise
    – Andy P
    Aug 2, 2023 at 9:18

5 Answers 5

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At same pressure, riding on hard surface like pavement, thinner narrower tires are:

  • Faster due to less air resistance than wider tires
  • Faster due to less weight, mainly on climbs, but do note that weight itself also increases rolling resistance
  • Slower due to more rolling resistance than wide tires, IF they are run at the same pressure

So it's complicated. Also, nobody runs narrow and wide tires at the same pressure. Firstly, the casing tension is proportional to tire width and tire pressure. So the wider tire you have, if you run the same pressure, the more casing tension you have. Eventually the casing tension is so high that the tire can't withstand it and explodes.

Also, at the same pressure, narrower tires have a long and narrow contact patch. Because the contact patch is long, it's deep. Wide tires have a short and wide contact patch. Because the contact patch is short, it's shallow. These two contact patches have the same surface are but different shapes. So at the same pressure, the wide tire deforms less vertically. Thus, it's less comfortable. This too explains why narrow and wide tires aren't run at the same pressure.

Also narrow tires are often run at very high pressures due to possible pinch flats. Wider tires are less susceptible to this, so they can be run at very low pressures.

So there are three factors to consider when deciding tire pressure: casing tension, how much the tire deforms vertically, and whether the tire at this pressure has enough resistance against pinch flats.

The question of whether wider tires have more rolling resistance than narrow tires is therefore very hard to answer, since you have to have some law of how to vary the tire pressure as a function of tire width.


However, all of this changes on loose surfaces. You can test this as follows: put 28mm slick tires on a road bike, pump them up to 7 bar, go riding on soft sand road that is wet (this is best done in regions that have snow because the melting water from snow will make the road deeply saturated in water). You will immediately notice that you will slow down quite a lot compared to hard pavement or even the same sand road when it is fully dry.

On loose surfaces, it is heavily beneficial to have a wide tire at low pressure instead of a narrow tire at high pressure. This is so beneficial that on loose surfaces, it almost always overcomes any air resistance drawback from the wide tires. If you can't ride more than 20 km/h due to rolling resistance slowing you down, air resistance is anyway so small that it doesn't matter. Reducing that rolling resistance matters a lot.


Because rolling resistance is a constant force and linear power, and wind resistance is a square force and cubic power, whether or not air resistance or rolling resistance matters more depends on the speed. On hard surfaces, it's hard to answer. On loose surfaces, the drawback from high rolling resistance of narrow high-pressure tires is so great that less rolling resistance almost always wins.

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As this is a mountain bike, the fastest tyres are probably those most appropriate for the surface you're riding on.

On dirt trails, you need grip to accelerate, turn, and brake. This is often best served by wider tyres with tread, which are slow on paved surfaces.

Riding even well-finished trails on slick touring tyres, which are far quicker on roads than MTB tyres, is slow going. I've done it. The lack of grip means slowing down more and earlier, and sometimes some wheelspin when you pedal hard.

Fairly smooth gravel is somewhere in between, as are gravel tyres.

If you've got a mountain bike and you're using it on the road - perhaps for commuting - your biggest benefit will come from using smoother tyres, though most of them are also thinner. Go too thin and the tyres won't fit the rim well. For typical hardtail stock wheels, slick tyres in the 35-45mm range will make a big difference, 50mm if you also want to handle rough but grippy surfaces.

Rather than concentrating on the brand, the specific model of tyre is more important. All the major manufacturers make knobbly tyres, road racing slicks, and endurance slicks. I have Schwalbe Nobby Nic on my MTB, and Schwalbe Marathon Supreme on my endurance road bike, sticking to examples from the brand you have.

Pressure is also crucial. Silca have a pressure calculator which is worth a look. Note their disclaimer - if the calculator produces a result outside the manufacturer's specified pressures, limit yourself to what that manufacturer says. This will still tell you which end of the range to inflate to.

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    Comments have been moved to chat; please do not continue the discussion here. Before posting a comment below this one, please review the purposes of comments. Comments that do not request clarification or suggest improvements usually belong as an answer, on Bicycles Meta, or in Bicycles Chat. Comments continuing discussion may be removed.
    – jimchristie
    Aug 3, 2023 at 16:15
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First, what do you mean by thickness? (Note, I wrote this before the OP clarified that they're on an MTB) Time trial tires have very thin casings. Performance road tires usually have two or three plies of casing material; the higher performance ones probably forego a puncture strip, but many others have that. The strip adds rolling resistance. For example, on bicyclerollingresistance.com, compare the Continental Grand Prix 5000 S TR to the 5000 AS TR - the latter is the endurance version of the tire, and I believe it has a puncture strip. Within a manufacturer, their TT tire, if they make one, will be the thinnest and the fastest. If they make an endurance road tire and a performance road tire, the latter will probably have a thinner casing, may forego the puncture strip, and will be faster.

To some extent, a thinner casing probably means less hysteresis loss when riding. When you go over a bump, the casing compresses, and then it rebounds. Some energy is lost as heat. The same is true for things like the kevlar (or whatever material) puncture strip.

However, note that tires also have friction between the tread and the road. I forget the technical term for this. In any case, tire makers will work with the chemical formulation of the tread to optimize between rolling resistance and grip (and whatever other characteristics). And some manufacturers, like Continental, Vittoria, and Schwalbe, are known to have good compounds, while others, like Maxxis and formerly Tufo, are behind the best in class. Again, you can verify this on the site mentioned above. So, the differences between manufactures for the same class of tire (e.g. comparing among endurance road tires) can be substantial.

Alternatively, by thinner, did you mean narrower? Here, wider tires can definitely have similar rolling resistance than narrower ones, and potentially less rolling resistance given that you selected an optimal pressure. Aerodynamically, all else equal, thinner should be faster, but you can design the wheel such that the wheel + tire system is fast with wider tires, e.g. many modern road wheels are converging on 28mm tires.

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  • Yes I mean the widthness of the tire. The amount of width of the tire, when you are looking the tire from the front of the bike face on - with the steering wheel being 90 degrees to the frame. So yes, the tire can in this sense be narrow or wide. Mine is quite wide, so I am thinking of swapping it for a narrower one, being under impressions that it would be faster then. Jul 31, 2023 at 22:12
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    @VladimirDespotovic I would not swap to a narrower tire. If we are talking a road bike with wide aero rims, the rims are designed to be aero at their current width. If your tires are a lot wider than the rim, there will be an aero penalty, but it’s probably small. However, I just realized, the Cube Aim is a mountain bike?
    – Weiwen Ng
    Aug 1, 2023 at 1:38
  • @WeiwenNg the name of the model (and the case in the question) is a bit confusing: "Cube Aim" is the model and is a entry-level MTB, "Race" is the variant.
    – Rеnаud
    Aug 1, 2023 at 5:34
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As a very, very general rule skinnier tyres are faster rolling, but there is really a whole heap more variables to consider than just the width of the tyre. Things like weight, tread patterns, tyre pressure all play a significant part in the equation, not a comprehensive list of factors of course. It's more than possible some wider tyre combos will roll faster than skinner tyres because of other factors such as construction.

Also, worth considering when evaluating tyre width choices is the rim internal width. Some rims will just plain work better on different rim.

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    One potentially major factor in that heap: wider tires will have less drop for a given pressure as the contact patch is wider. Less drop means less rolling resistance from hysteresis losses. Aug 1, 2023 at 0:17
  • @AndrewHenle I asked only about the tire width, not about other factors from the heap....but ok, worth noting. Aug 1, 2023 at 1:00
  • @AndrewHenle because of the contact patch curvature, a wider tire at the same pressure will also be harder than a narrow one. If you trust the bicyclerollingresistance.com measurements, the tire width doesn't make much difference if you inflate to recommended pressure. Until you start bottoming out the narrow tire, of course.
    – ojs
    Aug 1, 2023 at 7:36
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    Isn’t it unfair to compare different widths at the same pressure?
    – Michael
    Aug 1, 2023 at 10:18
  • @Michael no, if you don't get the result you want otherwise
    – ojs
    Aug 1, 2023 at 19:13
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It depends on the use of the mountain bike. Do you use it as a mountain bike? Or do you just use it on paved roads and cycling paths?

The MTB world is shifting towards wider and wider tyres to be faster. Even in cross-country where the world cup riders now regularly use 2.3" wide tyres. Such wide tyres are faster in a real MTB terrain, even if just cross-country and not enduro or downhill.

For cyclocross racing, the tyre size is kept at 33 mm by the rules, but most often the riders would happily go for wider ones, if they were allowed to do so. It would make them faster on the cyclocross course.

After the question edit:

If you just wast to be fast "of course" on a flat road than you mainly chose the wrong type of bike. It will never be as fast as a road bike but it can be made faster by dedicated for road use. These will be more narrow and have little tread (perhaps even slicks). The width will depend what your rims allow but remember that even in road racing the tyres get wider, 28 mm is now the norm. Do not become obsessed with as narrow as possible. The design of the tyre specifically for roads is more important.

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    Interestingly, narrow tires work better in very sloppy conditions (cyclocross and MTB). When world cup DH racers are riding the mud (not just wet dirt, but mud), they'll opt for something like the Maxxis Wet Scream (2.1" wide) and cut down the spikes to the estimated depth at which they'll slice through the slop down to firmer dirt. In muddy cyclocross courses, the 33 mm tires excel compared to what you'd normally "want" under other (drier) circumstances.
    – Paul H
    Aug 1, 2023 at 16:01
  • @PaulH Yes, if you have something hard that you can cut to, it will work. One needs quite significant tread for that. On rock gardens on an XC track gardens they would be lost with narrow tyres (but 2.1 is not that narrow, at least for XC). Aug 1, 2023 at 16:09

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