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Myths in cycling: wider tires are slower

renehersecycles.com

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Re: Myths in cycling: wider tires are slower

#361

Post by nikau »

jacquesm wrote: post #328
masklinn wrote: post #253

Earlier quoted context omitted.

> It's not a myth, it's just conditionally true. Sounds to me like it’s generally true, and conditionally not: in good condition with thin tires on a metal wheel good rim brakes can be better than disc. Je general case is thus that you’re better off with disc as default.

We have a pretty wide collection of bikes, and all of them are in tiptop shape. None of the bikes with rim brakes have the same kind of stopping power as the disc versions. They don't even come close. Maybe there is an ideal bike somewhere that can outperform any of the disk brake systems that we have but if it exists I haven't seen it. Ever. Of course this is still 'anecdata' but I've seen a lot of bikes. The people…

The difference is the modulation, especially with hydro discs.

Rim brakes are like drum brakes on cars, they are more binary with not enough braking power that then snap transitions to locking up.

hydro disc brakes let you brake hard and avoid lockups.

Re: Myths in cycling: wider tires are slower

#362

Post by jmilloy »

theelous3 wrote: post #317
jmilloy wrote: post #219

I think folks might be interested to consider some of the other myths and tests in the series, such as: * Titanium is ligther than steel * Fenders slow you down * Stiffer frames are faster * Disc brakes work better than rim brakes * Higher tire pressure is faster * Bigger wheels roll faster https://www.renehersecycles.com/category/myths-in-cycling/ For more nuanced tire testing and results, check out these two more r…

> Disc brakes work better than rim brakes They really do though. Hydraulic disk breaks have way more stopping power, higher resistance to wet and dirt, don't weaken with each use, and are both lower maintenance in the long and short term, and easier to service and get correct. It's not out of ignorance the bike uses who need brakes the most 100% use disks (mountain biking). The argument made is that "rim breaks are d…

I think the myth is "all disc brakes are always better than all rim brakes". There are definitely reasons it y situations to prefer disc brakes, especially hydraulic, but also reasons to prefer rim brakes.

Re: Myths in cycling: wider tires are slower

#363

Post by masklinn »

jacquesm wrote: post #328
masklinn wrote: post #253

Earlier quoted context omitted.

> It's not a myth, it's just conditionally true. Sounds to me like it’s generally true, and conditionally not: in good condition with thin tires on a metal wheel good rim brakes can be better than disc. Je general case is thus that you’re better off with disc as default.

We have a pretty wide collection of bikes, and all of them are in tiptop shape. None of the bikes with rim brakes have the same kind of stopping power as the disc versions. They don't even come close. Maybe there is an ideal bike somewhere that can outperform any of the disk brake systems that we have but if it exists I haven't seen it. Ever. Of course this is still 'anecdata' but I've seen a lot of bikes. The people…

> None of the bikes with rim brakes have the same kind of stopping power as the disc versions.

Yes I expect the people who say that rim brakes are better don’t mean "have better stopping powder" as that seems unlikely, but rather "have sufficient stopping power while being lighter / more flexible / …".

Re: Myths in cycling: wider tires are slower

#364

Post by jmilloy »

jacquesm wrote: post #328
masklinn wrote: post #253

Earlier quoted context omitted.

> It's not a myth, it's just conditionally true. Sounds to me like it’s generally true, and conditionally not: in good condition with thin tires on a metal wheel good rim brakes can be better than disc. Je general case is thus that you’re better off with disc as default.

We have a pretty wide collection of bikes, and all of them are in tiptop shape. None of the bikes with rim brakes have the same kind of stopping power as the disc versions. They don't even come close. Maybe there is an ideal bike somewhere that can outperform any of the disk brake systems that we have but if it exists I haven't seen it. Ever. Of course this is still 'anecdata' but I've seen a lot of bikes. The people…

I haven't had issues with any of my disc brakes overheating, but that sounds like one reason to prefer rim brakes, rim brakes cool better. That's not an issue for a lot of situations, though.

Re: Myths in cycling: wider tires are slower

#365

Post by unethical_ban »

rorykoehler wrote: post #250
plorkyeran wrote: post #36

Earlier quoted context omitted.

Yeah, when I first got my gravel bike I thought I'd be sacrificing some road performance for better flexibility and comfort, but that didn't happen. The actual result was that my times on smooth segments were unchanged and I've beaten many of my personal bests on rougher roads (and obviously it's much better on dirt). It's not a perfectly fair comparison because I did upgrade to a nicer bike in the process, but my pr…

Don't gravel bikes have much smaller gear ratios? There is no way a strong road cyclist would have the same times on a gravel bike as a road bike purely due to the size of the front chain ring. I run a semi-compact up front on my road bike and I can't go faster than 53kmh on the flat without my cadence getting too high to sustain for longer periods of time.

My 2019 Trek Crossrip has 48/32 and 11-32. Of course, you could switch those components up - the biggest difference between gravel and road is the clearance for wider tires, and "relaxed" or upright geometry, plus capability for more mounting.

And Cannondale even has a carbon frame with a front suspension and rear flex on the frame for a near-full-suspension behavior.

Re: Myths in cycling: wider tires are slower

#366

Post by jmilloy »

laputan_machine wrote: post #333
consp wrote: post #326

Earlier quoted context omitted.

> * Higher tire pressure is faster For semi-professionals sure this is a myth for normal road surfaces, but for every day use by normal people with no knowledge whatsoever putting just over 2 bar in their wheels since that is what their cars use you definitely win efficiency, al lot.

If I used 32psi in my bicycle tyres I'd be getting pinch flats all the time! I run 35x700c marathon plus', which requires a minimum of 65psi [4 bar] ( https://www.schwalbe.com/en/tour-reader/marathon-plus ) Maybe for mountain bike tyres that advice works well.

I use 30psi on my 35mm and 44mm tires on paved and unpaved surfaces all the time. Have you tried, with a good supple tire? Mine have a max of 65psi!

Re: Myths in cycling: wider tires are slower

#367

Post by jmilloy »

pharmakom wrote: post #277
jmilloy wrote: post #194

Earlier quoted context omitted.

Another big difference is simply the quality of the tire. A supple 48mm knobby could be faster than a stiff slick (and we know the width doesn't matter). The Rene Herse Oracle Ridge knobbies are 48mm, quite supple and corner well on the road, plus they are noise cancelling!

Width matters for air resistance. I can hear the air coming off my 2.1 inch tyres. Rene Herse knob bikes are still pretty loud in my experience!

Yeah, in the mid 40mm range I don't think the air resistance matters, but up above 50, you're starting to make tradeoffs.

Re: Myths in cycling: wider tires are slower

#368

Post by auxym »

stinos wrote: post #299
Swizec wrote: post #201

Earlier quoted context omitted.

In my neck of Europe those bikes reached peak popularity in the 90's and early 00's. We called them "city mountain bikes". Their distinguishing feature was that a "mountain bike" comes with gears (normal bikes don't), which was very popular. The city edition came with fenders, luggage racks, a nice bell, stand, etc. Big fat tyres, comfy geometry. The tires usually had a slick strip in the middle and grooves on the si…

These aren't the types of bikes meant by the one you're replying to, I think: these are basically mountain bikes with modifications for day to day road use. The other are gravel bikes (which is what I assume means the ones used in cyclocross i.e. a sturdier version of a road bike) modified for day to day road use. But yes these citybikes were very popular in Europe.

Indeed, for anyone curious, have a look at the 1985 Raleigh (a notable UK company at the time) catalog, and compare the "Road Sport" category with "Sport Touring": https://www.sheldonbrown.com/retroraleighs/catalogs/1985/ind...

Re: Myths in cycling: wider tires are slower

#369

Post by unethical_ban »

jiscariot wrote: post #137
haswell wrote: post #12

This is one of the reasons I love the emergence of the "Gravel" category of bikes. They look and have geometry similar to a road bike, but they have enough clearance for nice fat gravel tires. I ride in Chicago (shitty roads, potholes & construction are everywhere), and love that I can put nice 38mm+ GravelKing Slick tires on the bike, and still have no problem keeping up with most road bikes. I've gotten funny looks…

My only complaint about the gravel trend is that at the entry (and mid) level they are often using pretty crappy disc brakes when rim brakes would have been a better choice in 90% of cases. When they are hydraulic, they are a dream to use, but with a cable you really lose the brake feel.

Yeah, my gravel bike was $1000 new three years ago, and comes with "Spyre 2.0" cable disc brakes. Hydraulic brakes feel 1000% better, but I'd still rather have disc than rim. And mine are double caliper.

One thing I love about my brakes is having a second set of brake levers inline on the top of the bar - I believe the Shimano GX (gravel) series has that now for hydraulic. If I ever have to buy another gravel bike, it will have this feature.

Re: Myths in cycling: wider tires are slower

#370

Post by stinos »

mymythisisthis wrote: post #345
stinos wrote: post #299

Earlier quoted context omitted.

These aren't the types of bikes meant by the one you're replying to, I think: these are basically mountain bikes with modifications for day to day road use. The other are gravel bikes (which is what I assume means the ones used in cyclocross i.e. a sturdier version of a road bike) modified for day to day road use. But yes these citybikes were very popular in Europe.

Touring bike is my favourite. https://en.wikipedia.org/wiki/Touring_bicycle#/media/File:Lo... Very similar to cycle cross (a wide range of gears) https://upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Fo... The hybrid has straight handlebars https://upload.wikimedia.org/wikipedia/commons/thumb/2/22/AE... Mountain bikes, gravel bikes, are slow. Gearing is for climbing a mountain. https://upload.wikimedia.org/wikipe…

Mountain bikes, gravel bikes, are slow

Given the huge difference between the 2 I'm not sure what you mean? Also because these days 'mountain bike' is an umbrella term, whereas gravel bike is still rather specific. E.g. that last link shows already a rather specific segment of maountain bikes: dual suspension, quite a lot of travel on the front suspension, totally suited for going down the hill fast as well.

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