Live data from Hacker News

Myths in cycling: wider tires are slower

renehersecycles.com

321–330 of 419 posts

Re: Myths in cycling: wider tires are slower

#321

Wider tires are still slower BEYOND A CERTAIN SPEED as drag increases. Furthermore tire rolling resistance test are done on a bumpy surface, and 25 mm tires > 28 mm.

>tire rolling resistance test are done on a bumpy surface

Which ones are? The ones at bicyclerollingresistance.com aren't road-like-bumpy at least, and that's the most commonly cited page I know of for rolling resistance.

Re: Myths in cycling: wider tires are slower

#322

Earlier quoted context omitted.

I've been road riding with people who switched to gravel bikes and they were suddenly noticeably slower. They also seemed to run out of gas earlier which means they were expending more energy to keep up.

interesting, maybe different frame geometry contributed as well?

I would imagine this would be considerable. Improving your aero position is the easiest way to go faster.

Re: Myths in cycling: wider tires are slower

#323

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…

And calipers on disc brakes have a lot more grip on the disc than the rubber brake shoes on rim brakes, which - especially when wet - can be quite useless.

Re: Myths in cycling: wider tires are slower

#324
post #189

Earlier quoted context omitted.

And quite a bit of the money they spend comes from companies trying to sell gear to hobbyists. It's a rather wild mix between ride what makes you fast and ride to pretend that it makes you fast.

Not sure what gear Inoes grenadiers is selling to hobbyists.

Pinarello bikes, Shimano groupsets, Fizik saddles, Kask helmets, Castelli kit, Oakley glasses, and all the other things you see surrounding the fat guy at the coffee shop on a Sunday morning ;)

Re: Myths in cycling: wider tires are slower

#325

Earlier quoted context omitted.

These are interesting articles, but in https://www.renehersecycles.com/myth-12-disc-brakes-work-bet... , it just says outright "Many rim brakes for wide tires are too weak to do this quickly, so in the rain, you end up with almost no braking power at all." It's not a myth, it's just conditionally true.

You should also keep in mind that the articles are slightly dated, so technical improvements may have changed the equation. For example in the comments thread for the disc brake article, people mention that they cannot find disc rotors with sufficient size for tandems. With the rise of cargo and electric bikes, disc brakes with pretty massive stopping power have come to market. Mine can safely stop the bike, me, plus…

On tandems the problem hasn't been stopping power for years (every since we had hydraulic brakes this has been a solved problem). The bigger issue on a tandem is that when you're going downhill you will end up overheating your brake, whatever kind of system you are using. There is just too much kinetic energy to get rid of as heat for your normal brake system to be able to deal with.

Re: Myths in cycling: wider tires are slower

#326

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…

> * 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.

Re: Myths in cycling: wider tires are slower

#327
post #231

Earlier quoted context omitted.

Surly made a couple bike you could put fat tires on - their touring bike and a cyclocross bike. I don’t know if they’re still available but they were selling them in the mid-2000s

Definitely still available. That segment of the industry has exploded. Another great manufacturer for touring/adventure bikes is Bombtrack. Many touring/adventure bikes will double as way better commuter than a road bike I feel. They are set up for comfort, long hours in the saddle, and usually have with luggage mounts.

My 15 year old Surly Crosscheck is probably my most ridden bike - it was one of the 'first' gravel bikes (they've been making them for 20 years) before they really became a thing. The cantilever brakes are rubbish but that just makes it more fun.

Re: Myths in cycling: wider tires are slower

#328

Earlier quoted context omitted.

These are interesting articles, but in https://www.renehersecycles.com/myth-12-disc-brakes-work-bet... , it just says outright "Many rim brakes for wide tires are too weak to do this quickly, so in the rain, you end up with almost no braking power at all." It's not a myth, it's just conditionally true.

> 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 that still seem to push for rimbrakes here in Europe are typically semi-pro or pro cyclists, who may or may not have valid concerns regarding injury due to the disc edges being too sharp (they are now usually chamfered to allay this).

Re: Myths in cycling: wider tires are slower

#329

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.

If you can spin out a 50x11 or similar on the flat you're in a very small minority of cyclists...

Re: Myths in cycling: wider tires are slower

#330
post #31

Earlier quoted context omitted.

Yeah, my roady friends are jealous because I get to use my gravelbike off-road, and my mountainbike friends are jealous at me for being able to keep up with roadies. And all that for the price of one bike and an extra set of wheels with slicks! Canyon Grail here, yes the one with the weird cockpit :)

How off-road do you go? I have a gravel bike too, but I much prefer the MTB for rocky descents.

Yeah some of the gravel bike stuff really amazes me these days. I can't imagine doing some descents on anything but a fireroad with a gravel bike due to the un-slack geometry, but I've seen people bomb green downhill runs at some bike parks!
Post reply on HN