Are there reasons beyond the perception that the narrower tires are faster based on feel? A gear editor for his entire career, Matts journey to becoming a leading cycling tech journalist started in 1995, and hes been at it ever since; likely riding more cycling equipment than anyone on the planet along the way. The difference is smaller than many cyclists imagine the air inside a wide tire doesnt add weight but a wide tire has a little more rubber and casing. As long as you choose high performance ones, youll never go back. Faster than that, the aero penalty of the wider tire begins to overcome its rolling resistance advantage. On every track where Ive raced I was aware of how much better and faster a good supple tubular (eg Vittoria CX) feels compared to a cheaper vulcanized tub. The human body works similarly. Our online courses offer unprecedented opportunities for people who would otherwise have limited access to education. So 19 mm is probably the slowest you can ride. Comparing rolling resistance, a 25mm tubeless tyre at 95-100psi is the same as a 30mm tubeless tyre at 72-80psi.. And with bicycles, the tires are pretty much the only suspension one has. Highlights From the 2022 Tour de France Femmes, 7 Best Kickstands To Prop Up Any Type of Bicycle. Use wider tires because theyre faster, may be true for some riders, but definitely not all riders. Thats something, but over the course of a whole 160km ride with ups, downs, and flats, its probably not enough to make a dent in your time/speed. What if wider tires were a few percent slower, but their greater comfort reduced our fatigue? Tires are very interesting, because they influence three of the factors that most affect your speedweight, rolling resistance, and aerodynamics. Yet Froome and Co. all ride 700C wheels that are 10 cm larger than required As an extreme example, the Rawland Ulv we tested in the current Bicycle Quarterly with its 80 mm-wide tires was almost impossible to rock from side to side while climbing out of the saddle. This is because tyres dont work in isolation but need to be viewed as part of the wheel system. The trend has inexorably shifted towards wider tyres run at lower pressure. Most riders like you and me cant just focus on just one factorweight, rolling resistance, aerodynamicsand ignore practical considerations like comfort, puncture resistance, longevity, traction, and price. We ride our tires on gravel all the time. The first is friction what most people think of as rolling resistance. While the Classic 28s are wider, they also have different construction, use a different rubber compound, and have a different tread pattern. I dont even bother to un-weight the bike most of the time. That doesnt answer why riders believed that narrower tires are faster. In the 40s and 50s you can see tires getting narrower. I compared wide and narrow tires, 42 and 32 mm Clement Xplor MSO, on my cyclocross bike and found one drawback with wide tires the handling of the bike is worse, I think because contact patch of the front tire is almost square on the wide tires and more elongated in narrower tires. Even a professional bike racers power-to-weight ratio is far less than that of the slowest economy cars, and those dont exactly push you back in the seat when you floor the throttle. I think it would probably prove a big bag tyre with high TPI is the best. Additionally, Some of the bigger climbs encountered in racing are immediately followed by descents. For tire performance, the casing construction is more important than all other factors. Imagine a bean bag that drops on the ground without bouncing back all the energy is absorbed by friction between the beans. Can you tell me the total diameter of a Switchback Hill? You make a good point wide tires with excellent performance are few and far between. Talk about a win-win scenario! Best tubeless road tyres 2022: Cyclist's guide to road bike tubeless tyres (video), Which is faster: Aero vs lightweight wheels, Read our guide to how to convert and the best options here, Wider tyres and lower pressure make you faster. I have a bike with 28c wide tires, and it sure does feel different than my 23c tires since they are noir the same tire brand, its hard to say what the difference is though. Right now Im struggling with tire rolling resistance in the cold. Mine is Chuck. Overall excellent article, and I myself prefer wider tires (32mm). But what is less considered is how much actual energy that saves, and the subsequent effect that can unquestionably have on performance. We tested our tires on smooth pavement at29.5 km/h (18.3 mph), and found no speed difference between narrow and wide tires (see above). As it was, the 32 and 51 mm tires actually were fastest, while the 38 and 52 mm tires were slowest. develop their business skills and accelerate their career program. This is a great time to remind you that one of Bicyclings member perks is that members are free to email me anytime with their questions and Ill do my best to answer them. If it were a steep uphill-only time trial, the extra 90 grams might show up in your time. Others comments got me thinking more, now Im curious what the fastest width tire would be for like a 40 mile ride with average (2000ft ) of climbing would be. For pro racers, it makes sense to use 25 mm tires for most races. Its important to remember: Not all wide tires are fast. And that likely means the Classic has (at the same tire width) a higher CRR (measured rolling resistance) than the Race. A stiff, heavy touring tire is much slower than a supple high-performance tire no matter how wide it is. Weve tested this dozens of times, both with roll-down tests and with power meters above the averages of test runs with four sizes and the result is always the same: On smooth pavement, theres no performance difference between tires in the commonly used sizes (25-55 mm). Air at room temperature and sea level pressure weighs about 1 g per liter. Thats a much more excruciating scenario to test, I realize. As I mentioned in an earlier comment, I think the situation is more complex: When you climb out of the saddle, the lateral acceleration of the bike is actually quite large at 90 rpm, the bike has to go from zero to maximum and back to zero three times every second! Finally, aerodynamics. Yes, air does have mass, but it is pretty negligible. With a crosswind, the wider tire was very slightly less aerodynamic. Inertia works both ways. But how the tyre performs is a huge component of speed and is an area with the potential to unlock significant power savings. Rene Herse Cycles makes high-performance tires, handlebars and other components for road, all-road and gravel bikes. Equalize the bike weight using water bottles filled with weight for the lighter wheels, empty bottles for the heavier wheels. We havent tested this, but it stands to reason that sturdy tires with more rubber suffer more from this effect than tires with supple, thin casings. A wide [internal] rim profile allows the tyre beads to sit further apart, ideally making the sidewalls more upright, like an inverted U. Its too much for a simple blog post. But in theory, a larger diameter wheel due to wider tire will make the bike ride differently. The question is, when does the increased aerodynamic drag of a wider tire swamp its lower rolling resistance? The reason appears to be that the rubber gets stiffer when its cold. I commute on 42 mm tires. All I hear is wider is faster, but when does a wider tire actually become slower? What all this means: If you run wider tires at lower pressures, you increase the flex of the tire (negative), but you reduce the suspension losses (positive): the two effects cancel each other, and your speed remains the same. Even on very smooth asphalt, you dont lose anything by going to wider tires (at least up to 54 mm). Deduct the smaller, lighter rims and shorter spokes, and the difference is even smaller. What we needed to know was how much speed we would give up by going to wider tires. This meant that we were looking at the entire system, not just the tire itself. After doing research on just Schwinn, its obvious narrow tires are a product of marketing and reducing weight. Air has mass. Its true that a higher pressure effectively reduces how much a tyre deforms and hence lowers energy loss, but thats only really of benefit if were riding on perfectly smooth surfaces, like a velodrome, Marchment says. Dont underestimate the persuasion of anecdotal evidence- the best argument you could make would be dropping them. The increased frontal area of a wider tirethe front tire is the leading edge of your entire aero profiledoes increase your aerodynamic drag. We found that they all perform the same. First we had the advent of electronic gearing and disc brakes, and now it seems the traditional 23mm tyre is about to be consigned to history. Our tests clearly show a narrow tyre and high air pressure do not provide low rolling resistance, says Wheel Energys president, Petri Hankiola. If somebody tells you otherwise, ask them why professional racers dont use the smallest (and thus lightest) wheels the rules allow. Regarding cost, the cost-per-mile of wide tires actually is far lower than that of narrow ones, because wide tires wear so much slower. And yet, when we repeated our tests with a different methodology (power meter vs. roll-down), the results remained the same. Based on this and other testing, we developed our Rene Herse tires and optimized them for performance and comfort on real roads. successful learners are eligible for higher studies and to attempt competitive All rights reserved. Getting bicycle riders to accept this concept was like yelling into a hurricane for years, but thanks to you and Josh of Zipp/Silca its finally being accepted. I get a lot of general questions about whats better or faster. We know the benefits weve discussed so far to be true and quantifiable, Marchment says, but there is a third level that is far less understood, and it could prove to be the biggest benefit of all. I think youll find that a wider tire not only wont get pinch flats, but itll also roll over those jolts much better. >Thus, every climb is a long series of small accelerations, resulting in what I believe would be a more significant cumulative effect of the otherwise insignificant weight difference felt in a single acceleration. Excellent question Geoff. Wider tyres run at lower pressures dont only make your ride more comfortable they can make you faster too. I get that. If the wider ones were slower, wed expect to see a general trend in our data. For the answer well pass the baton back to Marchment. Keep the test double-blind and use several testers Similar to our tests of frame stiffness, but actually less involved no need to build four identical frames and get identical parts kits to build them up. Ive been riding wider tires (28c) on my road bike for years now because of some of your testing, and have enjoyed the comfort advantage. And on rough roads, wider tires are definitely faster. Would you recommend a set of your tires for the trip? If you flat in every 10th race, but win half of the other 9 due to the better-accelerating wheels, you are way ahead of the odds! And then there is the added clothing that constricts your movements. co2 weighs 1.52 times as much as air, so that correlates to air weights of 7.9 and 10.5 grams. so unlike on the road, the perfect tire width shouldnt take long to establish. I guess it depends on the terrain and everything. Weve put my Firefly through our back-to-back hillclimb tests, and its performance matches that of the best bikes weve tested. I think the myth is mostly due to the difficulty (and expense) of finding high quality wide tires. For the rest of us, those five seconds arent that important compared to improved comfort and better grip, plus the ability to go on rough roads. It seems to go against common sense. or do you think Id be better going with a stiff touring tires to avoid flats, sidewall tears etc. For me, at this moment, anything smaller than a 28mm tyre doesnt make any sense. Specifically, Wont this make the wider tires harder to accelerate? Road cycling purists are tearing out the last of their hair. I have a feeling youd make a good one. What this means for us riders is that we can choose wide or narrow tires, based on what we like, without having to worry about performance. We may earn commission if you buy from a link. I get there are a lot of variables at play here such as aerodynamics, casing, tread, weight, etc so lets use the bon jon tread/ casing as an example. (Running the first tire again makes sure that conditions havent changed during our test runs.) Even then, the wider tires required only 5 watt more on real roads, the reduced suspension losses probably make up for that. I raced against him many times. the 10/12 Board And with all tires, there are variations in rubber coating of the sidewalls, etc. What would be the fastest width of this tire all the way from 19mm to 50+ mm, what is the fastest width given all the variables? And of course, since the supple casing absorbs vibrations better, a high-performance tires is more comfortable, too. I averaged about 7 MPH on a recent ride, which would be fine if it was due to snow, but even on the cleared road sections I could only cruise at 9 MPH on the fatbike, where I know Ive done 12-14 MPH in the summer with the same bike and tires. Lighter wheels/tires decelerate faster too. With the right support from the rim shape, tyres become like a suspension system and really filter out the vibrations. https://bikehistory.org/catalogs/1964.html. Just read the request for real names. in KSA, UAE, Qatar, Kuwait, Oman and Bahrain. Our Degree programs are offered by UGC approved Indian universities and recognized by competent authorities, thus successful learners are eligible for higher studies in regular mode and attempting PSC/UPSC exams. You also have to remember that while we use tires that in theory use the same casing, tread thickness, etc. Like you say, other aspects of the bike do seem to make noticeable differences in climbing. Thanks, this is interesting, and it takes a while to understand what the results mean in practice. I recently got a question from a reader (see below) that illustrates why Im careful to dole out generalist answers and why you often cant focus on just one area of equipment performance and ignore the rest of the picture. Weve identified greater benefits to speed by taking a more holistic approach to how rims and tyres interact. I realise your article is about tyre width specifically but dont you think TPI (threads per inch) is also very important in handling and speed of a tyre. There are two reasons why cyclists used to believe that narrow tires were faster: 1. Thanks for the interesting article. Cycling equipment is often confounding. Thats whats tricky about tires; you need to balance a lot of factors. If you wanted to go fast, you chose narrow tires. The reduced sensation of fatigue allows the rider to focus more exclusively on smooth power input through the pedals. But all this was forgotten in later decades, as racers went to narrower and narrower tires. Above is just one of many test sessions, with Rene Herse Extralight tires. It is harder to maintain the same speed as someone on a 700c wheeled bike. This wasnt what we expected! MBA is a two year master degree program for students who want to gain the confidence to lead boldly and challenge conventional thinking in the global marketplace. As to climbing and descending, David Levy of Ti Cycles used to race a 650C bike in the hilly road races of the Pacific Northwest. Its half gravel road (with a reputation for wrecking car tires) and half rough paved road, about 1400 km in total. The thinking probably was that as a sprinter, Saronni would benefit from the smaller and lighter wheels. This equates to less deformation of the tyre carcass overall as it rolls and less deformation is less wasted energy. After all, you rock the bike to get more power, and you need something to push against. Tempted to convert to tubeless? What about the aerodynamics of wider tires? You went from Cadexs Race 25 to the Cadex Classics 28, so lets talk about the differences. If you like the buzzy, connected-to-the-road feel of a racing bike, choose narrower tires. If you climb out of the saddle, then you rock the bike from side to side, and there, the weight and rotational inertia suddenly become important. A transition from a special climbing bike to a dangerous downhill on unfamiliar equipment could spell disaster. Inflating your tires harder is a simple way of tricking your brain into feeling that you are going faster, but if you have a bike computer, itll tell you that you havent actually increased your speed. The 53s are probably overkill (I only weigh 140lbs) but theyre my favorite. Ive long forgotten the gas equations, but a skinny high pressure tire and a fat low pressure tire may have the same mass of air within, but that air absolutely has mass. Perhaps I have misunderstood your statement, but air doesnt weigh anything is incorrect. I thanks for the reply. But now weve stepped away from looking at just that alone. The difference in wheel diameter due to larger tires is relatively small. We can say that even on smooth roads a 44 mm tire rolls as fast as a 28 mm tire. As usual, thanks for pointing this out. They did their own testing that confirmed our results, and soon pro racers moved from 23 to 25 mm tires. But the thinking was thatin practice, the lower pressure at which wider tires must run limited their performance. Clearly, the smaller wheels didnt offer a worth-while advantage as a high-level racer in a field of similar strength, you know that you win only if all the stars align. This is especially evident in mud, rough surface, and for a light cyclist (60 kg). We often hear reducing tyre pressure referred to in discussions around improving comfort, which stands to reason, and thats a benefit not to be undervalued. Probably Michelin or some other tire company decided to make tires narrower to conserve resources or to make more money per tire sale. Please excuse the tangential question, but what bar tape is pictured at the top of this post? For the actual data, please check the back issues of Bicycle Quarterly. If youre getting pinch flats and bending rims thats a sure sign your tires are way too narrow. Tests for rolling resistance are unequivocal, and it is now widely understood that wider tyres actually have lower friction at an equal pressure, he adds. And last one that comes to my mind, what about say 24 tires on mountain bikes. This is a regular part of racer conversation at a velodrome, how the surface is, where the rougher and less rough parts are. Do you think the result generalizes well to other kind of tires that are identical except for the width, whatever that means, or are there certain kind of tires where things would likely be different? Third is the energy expended by the rider as a result of the physical work muscles have to do to absorb road shocks and vibration. In other words, a bike with narrow tires feels faster even though it may actually be slower. have discontinued my MBA as I got a sudden job opportunity after Tire width influences the feel of the bike, but not its speed. It's important to note that the change to the Classics tire with increased puncture resistance, a different compound, and a tread pattern designed for wetter and rougher roads played a large part in this. And yet, even though many have tried smaller wheels, all have returned to 700C wheels probably because the larger wheels handle better due to their optimized rotational inertia. In ideal circumstances and lighting, avoiding those sharp jolts is the best option, but in practice, thats not always an option. Cheers, Would be true of bikes made in Europe too except for different wheel sizes. Read our guide to how to convert and the best options here. Conversely, wide tires vibrate less, and thus feel slow to many cyclists. My long-term average speed on my Surly Pugsley, with knobby 3.8 (96 mm) tires is 10 MPH. So for almost a century, narrow tires felt faster and tested faster in the laboratory. Had you swapped a Race 25 for a Race 28, I think you wouldve been hard-pressed to feel a differenceat a 32kph average pace, the wider tires just might have even been faster. Theres no situation where I want to ride any tire as narrow as 25mm, especially not commuting. The shape of a tyre once mounted and inflated is the most critical factor in determining how it performs, both individually and as part of that system with the wheel rim. When you say that performance was constant between 2554mm, what is the measurement error at that interval? I often hear the big negative tire/speed/aero comments when riders look at my wheels but lately I ask if they have documented evidence to support their claim. Its Hankiolas final statement that really opens up the wider tyre discussion the opportunity to use a larger volume tyre at lower pressure for the same rolling resistance. Some people realized thatin theory, wider tires are faster due to their shorter contact patch, which deforms less as they roll. If a wide tyre is fitted on a narrow rim it will have mostly negative effects on performance, says Bastien Donz, wheel product manager at American brand Zipp. Now, with my 42s, 5000 miles is normal, and often, they last even longer. Good question! The fastest tires are also the least durable. Weve tested on rougher surfaces in the past, and there, wider tires are significantly faster. Developing a conducive digital environment where students can pursue their 10/12 level, degree and post graduate programs from the comfort of their homes even if they are attending a regular course at college/school or working. The tyre will be pinched at its base, creating a lightbulb shape, so the tyre isnt well supported and can feel unstable as it can roll left and right. All the time were experiencing vibration transmitted through the bike to our bodies, our muscles are having to do physical work to absorb this, Marchment adds. Narrower is lighter for racing in hills but you also can make more tires with given material quantity. Generally the larger tired wheel will accelerate slower, but will maintain a higher speed at the same power output. 2. I for one can definitely notice when im climbing with my racing wheels and racing tires vs heavier wheels and tires, but I dont think the weight difference between a 25mm and 54mm tire would be inconsequential. Really! One issue I face is pinch flats on rough spots if my tire pressure is lower than 80psi or so (in 20 years of commuting, Ive bent 3 rims irreparably on road imperfectionsI love Denver, but our pavement sucks). Hi, Jan Looking at the claimed weights, the Race 25s weigh 270g per tire and the Classic 28s are 315g per tire. Its conceivable that your bike will climb slightly slower (or faster) if you go to wider tires. Why did it take almost a century to rediscover this? Plus, speed is just one factor to consider when considering whether or not to use a wider, or any, tire. test, which makes it an ideal choice for Indians residing As a Post Script Andy Stow asked above about fat bike tires and his feeling of riding on molasses. There was no doubt that the narrowest tires were slower than slightly wider ones. A wider tires wont be much slower, but itll be a little heavier, and even if the difference is mostly psychologic, it can make a difference. Gear-obsessed editors choose every product we review. And its not a passive process. However, narrow tires also increase the frequency of the vibrations they transmit, creating the same effect without going any faster. A 32mm tire will give a wheel a larger diameter than a 20mm tire. But bikes arent simple. And the results were surprising. I dont know of any fat-bike tires that have a high-performance casing, so at least for now, we can say that fat-bike tires will be slower if not due to their width, then due to their construction. I suspect it was indeed the placebo effect of the increased vibrations. Long ago, cyclists used to know this. The same gear rolls further with wider tires, making it harder to pedal, which may contribute to the perception that wider tires are slower. If you can get a 5% advantage due to smaller wheels, youll take the risk that your race is over if you have a flat and cant get a wheel in your size. Since overall bike weight affects climbing speed, the small extra weight of a wider tire will cost a little speed. Im a firm believer in your approach to dispel these myths and appreciate the time and effort that you have taken to do this in a careful empirical manner. Thanks. Is it a question of familiarity? While fat tires are heavy and stiff, Cardiovascular and metabolic inefficiencies are an important consideration for riding in cold weather. However, we now offer Mawares leather tape that is also relatively thin, in addition to the thicker Gilles Berthoud handlebar tape. Regarding tire weight, consider that you need a smaller wheel with the wider tire to keep the handling the same (and to fit it into a frame). Matches my own impression I cant find any evidence that wider tires climb slower (comparing Compass EL to Compass EL). Quite a few pros tried smaller wheels. And the worst argument would be getting dropped, evidence be damned. As to the actual on-the-road speed of your bike, there are many factors see also the previous comment about climbing speed. Weve found in this example a 28mm tyre to be optimal, with pressures in the range of 79-84psi at the rear and 75-79psi at the front. Thanks. Basically, a lot more going on than a myth or belief. Peter Marchment, co-founder of Hunt Wheels, highlights three. Add a fourth win: lower cost, because you get more miles out of them. On my steel touring bike with 38 mm and 32 mm Compass tires, its 12 MPH. Its seems that the time has come to exile skinny rubber and those outmoded high pressures and accept that the research all points to one thing: go wide or go home. Every motor sport that races on rubber tires uses the biggest ones the rules allow and puts in as little air pressure as they can get away with. But obviously, most of us dont ride bikes on velodromes. Give wider tires a try. Its really interesting what weve found in researching the evolution of our rim shapes actually, we have been blown away by what weve found. You may be able to find more information about this and similar content at piano.io, Patagonias Fall 2022 Collection Lauches Today, The Best Brake Cable Kits for DIY Maintenance, The 7 Best Bottom Brackets for Upgrading Your Ride, Best Bike Fenders to Keep You and Your Ride Clean, 8 Best Bike Stems for Upgrading Your Ride, Save Big on Rainy-Day Cycling Gear at Amazon Now. This will affect performance perception and ride quality. Then we tested wider tires, and realized that the performance of tires doesnt change as they get wider than 25 mm: A 32 mm tire rolls as fast as a 28 mm, which performs the same as a 25 mm tire. It takes eight times more power to ride 64kph (40 mph) than it does 32 kph (20 mph) because of the increased air resistance. So the supple casing uses less energy on both counts. Your planned ride sounds like a lot of fun, and a perfect place for our tires: a mix of pavement and grael. On rough roads, they are faster, on a super-smooth wooden track, they may be a bit slower It was relatively thin leather tape, which many riders liked. Dead: Aluminum Frames, Analog Shifting, Rim Brakes, Easy Tips to Help Find Your Ideal Tire Pressure, This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. On my training wheels, I had stiff, kevlar-belted tires. At some point tires have diminishing returns based on how wide they are, otherwise we would be all racing on fat bike tires on the road. The rim is so important in making this possible. Even though some weighed over 40 pounds. And a 32mm tyre is only about 2 watts slower than an equivalent 28mm tyre. Wont this make the wider tires harder to accelerate? So tire performance is also affected by the fact that wider tires are also taller tires. Wide tires are just as fast and the reduced mental (and physical) effort spent on avoiding bumps is such a relief. Aero is still a big deal, obviously, as is weight, but these are gains that have already been mostly exploited. I wouldnt be surprised if they soon would ride 28 or even 30 mm tires, especially if their sponsors are starting to push wider tires on road bikes. For the same reason, tires have less grip in cold weather. The professional preference for 700c wheels might well be related to the logistics of running different sized wheels, it would seem prohibitive.