Myths in Cycling (1): Wider Tires Are Slower (2018) | Hacker News Reader

Myths in Cycling (1): Wider Tires Are Slower (2018)

janheine.wordpress.com

50 pointstokai32 comments

> The UCI requires a minimum wheel size of 55 cm, yet racers use 700C wheels that are 10 cm larger than required. If wheel weight mattered as much as most cyclists imagine, then pros using the smallest wheels would win every race. 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. (But that is a topic for another post.)

I know this! The answer is because the neutral van only carries 700c wheels. If a rider gets a flat the wheel needs to be replaced quickly thus it's advantageous to use the most common wheel type. It is explained in this video by a professional cyclist: https://www.youtube.com/watch?v=jLnwR0ZxhcI

Wider tires are discussed in this video (also by GCN): https://www.youtube.com/watch?v=yrHxQg1OW0A They also find that wider tires are slightly faster. Although they discuss widths of 23 vs 25 or 28 mm which seem like a minor difference for most cyclists. But probably makes a world of difference for professionals.

Although I, since a couple of years, ride (and preach) 50mm tires I believe it should be mentioned that Jan Heine's writings aren't exactly independent and objective research. He makes his money selling (mostly) wide and supple tires (Rene Herse, formerly Compass). They're not always as superior[1] as he likes to point out.

If you want to try wider tires (and your frame can fit them) there are alternatives to (the expensive) Compass tires. Try Maxxis DTH for 26" wheels and Torch for 28". Panaracer makes a bunch of supple and wide models. Pacenti Pari-Moto (made by Panaracer) nice and cheap. Also have a look at Schwalbe G-One Speed (available in a wide selection of sizes). Maxxis are cheaper in the US, Schwalbe are cheaper in Europe.

[1] https://www.bicyclerollingresistance.com/tour-reviews/compas...

Since there's a placebo effect mentioned in the article, I wonder if they double-blinded the tests? They don't say if they did, and it would be hard to do.

Surprised clipless pedals aren't included in the list of myths.

These sorts of myths exist in many sports; I am fascinated by them.

What's the myth with clipless pedals?

https://bicycles.stackexchange.com/questions/14059/are-there...

https://www.youtube.com/watch?v=CNedIJBZpgM

https://www.youtube.com/watch?v=FV0Fz2i2a8s

They're universally recommended as an entry to "serious" biking even though there's no scientific evidence they improve power or speed at all (except maybe marginally in accelerating from a dead stop).

For what it's worth, I have used and continue to use on occasion flats, clips, and clipless, and I prefer some kind of securing mechanism just because it's "set it and forget it" (I prefer clips actually).

However, somewhere in that first set of links (or in a link from one of the links) there's a long essay explaining that people feel less secure on flats because they are used optimally with a different foot position. That is, on clips and clipless you push with the front of your foot, and there's an argument that flats you should push with the middle of your foot. I've been trying this lately and it seems true to me. So some complaints about foot security might have to do with that; people trying the same foot position on both might be doing the wrong thing.

Also, a lot of money has gone into improving clipless pedals, and not so much on flats or clips, so there's some unfair comparisons there too.

Does there need to be scientific evidence to convince you? Maybe you should do a time trial test up a mountain with flats vs clip less. Clip less provides the ability to apply power through the bottom of the stroke, which provides significant benefits when going uphill. Furthermore, you don’t need to worry about keeping proper position on the pedal as you do with flats, which is actually a non trivial mental burden, especially during high torque times like sprints. If you’re just cruising on a flat, flats are fine, but if you plan to be riding seriously on uphills and doing sprints, clipless is the way to go.

Clip less provides the ability to apply power through the bottom of the stroke, which provides significant benefits when going uphill.

Only if you've never learnt how to spin.

I used to think like this, but it isn't true. After riding flats, rat traps, and clipless, I can say with confidence that clipless peddles are more efficient when climbing hills. I don't think it is as much about providing power on the bottom as it is about being able to pull up while going through the top. It especially makes it easier to keep a consistent tension while doing long uphill climbs. Rat traps work too, but I found they would catch on things constantly. That said, I use a pedal which is clipless on one side, and flat on the other. Depending on the situation I might use one side or the other (i.e. I might switch to my flats if I am riding in a busy downtown area where I might have to stop unexpectedly). Good technique will of course help you whether you are using clipless or flats.

What does this mean?

Knowing how to flex your ankles and set the seatpost height and gear ratio correctly lends itself to a style known as spinning that reduces the need to have the foot completely latched into a pedal while you mash and pull.

I also prefer toe clips alone, but a big part of why is that it forces you to push from around the ball of the foot instead of the arch/middle, and there's practically nothing to think about like with clipless. I was in Amsterdam a few weeks ago and rented bikes with my family - we all had sore arches after riding around 10 miles because without thinking that's what you naturally do. I ride pretty often and since I started using toe clips for every commute and clipless for every weekend training ride I've never had any foot discomfort.

I've noticed the same thing with arch pain on flats. However, when I started pushing from the middle of the foot, rather than the ball of the foot, that arch pain went away. The problem then that is that then I don't think I was able to extend my foot all the way through the down stroke. However, all that means is that I probably should be using shorter crank length with flats (as opposed to clips or clipless).

I've sort of become convinced that with the right bike fit, crank length, foot position, and good pedals, there's probably not really any meaningful difference between the pedal options overall. I don't mean that to denigrate anything, just that they all probably will work well depending on the person, and I don't know that moving to clipless needs to be a rite of passage for anyone necessarily.

I suspect OP is referring to the idea that you can get significant power returns on the upstroke with clipless pedals. This is definitely questionable. However clipless pedals are still a good idea because your feet don't slide off the pedals. Especially in wet weather they are dramatically safer than flat pedals.

What about the flat pedals with metal nubs standing out? I've tried those and sliding on these pedals was pretty much impossible, at least with the shoes I used.

I think I know what you are talking about. Basically it depends on the situation. With clipless pedals, your feet are pretty much locked in place without having to think about it. With flat pedals, they are only really in contact with the pedal when you are pushing down.

If you are riding a bike leisurely at say 12 kph down the street, clipless pedals aren't going to be useful and might even get in your way. If you are riding in traffic at 30-40 kph, then they can literally be a life saver. Over 90 RPM it's hard to keep your feet on the pedals. So if you need a sudden burst of speed when in a low gear, then this will make sure your feet on on the pedals. Also if it's raining and you hit a pot hole, for instance, your feet will be on the pedals. This really helps in keeping control.

If you've never tried them before, I highly recommend it. I never once fell off my bike due to clipless pedals, although some people do. Even though some people fall off when they first start, I've never met anyone who preferred flat pedals after trying clipless for a while.

The one place I would not use clipless pedals is if I was doing a lot of off-road stuff. I know some people use them anyway, but if you need to put your foot down regularly, it's pretty difficult IMHO.

It depends what kind of off-road you mean, but for downhill MTB clipless use has overtook flat pedals. There has been a bit of a resurgence in the use of flat pedals though with Sam Hill's recent wins on flats. I am still a fan of flats for downhill, but I learned riding on flats.

I'm not sure how it's questionable, you can definitely put much more torque on the pedals when you can push down with one foot and pull on the other, for sprinting in a big gear or climbing.

The questionable part is, do people apply pressure on anything but the down pedal stroke when they're seated, and riding normally. At least for me, the answer is no.

But they're still nice to have, especially on a single speed or fixed gear. And for fixed gear, flat pedals are unsafe. They give you a lot more control.

I like clipless because they enforce better form and don't stray into the chain.

Safer until you forget to unclip at a stop.

After the second time you forget, you'll never forget again.

It's like picking the soldering iron up by the wrong end, I watched both of my kids do that. Once.

I think the 'myth' is that you can use the entire pedal stroke, rather than only pedaling on the down stroke.

Obviously, it's not really a myth, you can definitely do it. But I don't think most people actually do.

Compared to cages where you're so tightened in you lose feeling in your feet?

Triathletes would have switched to cages years ago if this was a myth.

I think the most common myth is that you should get an athletic bike if you want to get into bicycling.

This is not a new theoretical result, but it is a new practical reality. Tires are built differently today due to better materials like multi-layer puncture-resistant weaves. It used to be a thick layer of rubber in the middle and relatively weak sidewalls, so the contact profile would be nearly cylindrical. Lower pressures were awful, and the sidewalls would blow out on a bigger tire above 60psi.

There are a few other differences that matter a lot in the peloton. Power transfer is important for holding a tight draft. A pro on 28s will definitely notice a delayed/muted impulse response over 23s. I believe this also affects pedaling efficiency, as any MTB racer on a soft tail will attest. Narrow tires also give much better handling/braking and therefore much faster descents. Fat tires braking gives this weird kick-back that feels like it’s tossing you over.

Still, I ride fatties. I love the way they smooth out the road. But they’re not necessarily faster.

contact profile would be nearly cylindrical

How would a 2-dimensional contact profile be describable with a 3-dimensional object?

A pro on 28s will definitely notice a delayed/muted impulse response over 23s.

Really? Is this a measured, observable fact or another piece of woo that cyclists have believed for donkeys' years?

I believe this also affects pedaling efficiency, as any MTB racer on a soft tail will attest.

Are you seriously claiming that bouncing up and down on a rear-suspended MTB is comparable to riding on a 622-28 inflated to 620kPa ?

Narrow tires also give much better handling/braking and therefore much faster descents. Fat tires braking gives this weird kick-back that feels like it’s tossing you over.

Again, I have to ask for specifics and measurements.

I will counter-claim that that the inferior response of over-inflated narrow tires to road imperfections leads to much more jittery descents and inferior handling on most surfaces, ths leading to slower descents (that's what all the Bicycle Quarterly tests of roll-downs are about).

The width is crawling upwards for the pro riders. No sub 25mm tire was used in the Tour de France the last two years, iirc.

I can't see them going over 30mm though. The article underplays aerodynamics in my opinion.

Any idea if pro riders increasing their tire size is associated with them also transitioning to disk brakes? Disks solve at least half the problem - braking. (Narrow tires may still handle better in other ways though).

Yeah, disk breaks are definitely helping the trend. From the head mechanic of EF Education last year:

«The disc-brake thing has gained real momentum, so on those frames you can certainly run wider tires because there's the clearance for it. I could see it evolving to 26mm or 27 mm as the standard road-racing tire, sure. Why not.»

https://www.businessinsider.com/tour-de-france-wider-tires-l...

As a competitive cyclist and someone who spends far too much time thinking and talking about bikes, I've never heard any of these claims, and in fact most of them are the opposite of the common consensus among cyclists.

Makes gravel bikes even more attractive.

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