News for hackers. Stuff that matters.
Re:Myths in cycling: wider tires are slower by jmilloy on Monday June 14, 2021 @08:57PM (#27510207)
Indeed! In the same series: Myth: disc brakes work better than rim brakes[0]. The rim is the rotor of a bit disc brake rotor that cools better and doesn't add any weight. But the wider tires make disc brakes a necessary choice.

[0] https://www.renehersecycles.com/myth-12-disc-brakes-work-bet...

Re:Myths in cycling: wider tires are slower by sliken on Tuesday June 15, 2021 @02:41AM (#27512052)
Heh, rene makes a business out of being different, and has some good ideas, but they do push it to far sometimes.

Sure I get it, a stoppie shows that the brakes are not a bottleneck, it's the traction. So sure, sometimes, on some bikes, with some riders, under some conditions you get perfect braking.

However in the real world there's various rim surfaces (aluminum, steel, carbon fiber), with a variation of water, grit, sand, snow, ice to complicate things. Cable have friction and slack. Rims sometimes are not perfectly round/true in both horizontal and vertical directions. Brake pads are rarely perfectly aligned (the alignment changes as the pads wear), rarely nice soft rubber (they glaze over with heat and/or age), and are rarely braking on perfectly clean rims.

So yes, I've done a stoppie with rim brakes, but the average performance of average hydraulic disc brakes greatly exceeds the average performance of rim brakes. Their other complaint about being grabby is highly brand specific, plenty offer great modulation. Not only to discs brake better, modulate better, and tolerate temp changes better better, but they also tend to apply more even pressure. Even small differences in trueness tend to create spots on the wheel that brake less or brake more.

I didn't realize how big the difference was, or the habits I had with rim brakes. Took me awhile to unlearn dragging my brakes when ever I hit a puddle, waiting for them to catch again.

Sure if you have a pro mechanic realign your pads before every ride you'll rarely run into an issue that rim brakes handle well. However if you spend more time riding than maintenance discs will serve you well.

There's a reason even the road racers, the most conservative of the bicyclist, are switching to discs.

Re:Myths in cycling: wider tires are slower by discreteevent on Tuesday June 15, 2021 @05:11AM (#27512872)
Agreed on everything except the road racers. Maybe some want discs but the pros don't. Discs are more likely to rub for them because pro cyclists generate enough power to twist the wheel. If you are trying to gain seconds over a few hours then the sound of rubbing must be torture. Chris Froome spoke out about it recently. Team Ineos just won the Giro and they don't use rim brakes because their sponsor does not oblige them to. It looks like the reason pro racers have discs is because the bike industry makes them. This is so that they can sell new bikes to people who already have a perfectly good one. It makes no sense for pro riders to have disc brakes. Their high end rim brakes are looked after by mechanics, they are lighter, they don't rub, wheel changes are easier and pros don't do a lot of braking anyway.
Re:Myths in cycling: wider tires are slower by jmilloy on Tuesday June 15, 2021 @09:24AM (#27515080)
This is something that I think a lot of people at overlooking even they reference pro racing: they ride the bikes their sponsors make them ride. And the sponsors have incentives that are not strictly limited to winning.
Re:Myths in cycling: wider tires are slower by mariusor on Tuesday June 15, 2021 @08:44AM (#27514453)
> and pros don't do a lot of braking anyway.

That's just not true, there's plenty of braking in the mountain stages. I sincerely doubt that going 90-100Km/h into a hairpin is easier with rim brakes.

Ineos had two accidents this season on descents, first with Moscon in the Giro and then with Thomas in Criterium du Dauphine and even if they might have been just flukes, I'm sure the team is asking themselves questions.

Re:Myths in cycling: wider tires are slower by petre on Tuesday June 15, 2021 @09:46AM (#27515456)
The industry can sell MTBs and gravel bikes where disc brakes have benefits. And now e-bikes, that's a huge market.
Re:Myths in cycling: wider tires are slower by darkwater on Tuesday June 15, 2021 @02:48AM (#27512122)
When I was a city rider to commute, pads alignment was a real PITA and the main reason that made me switch to disc brakes. I was always feeling braked and spending more effort than really needed because one pad was touching the rim. With disc brakes that feeling disappeared and never came back, although you still need to do some maintenance from time to time.
Re:Myths in cycling: wider tires are slower by sliken on Tuesday June 15, 2021 @03:06AM (#27512220)
Heh, yes, less maintenance, but also less finicky.

Brake pads on rim brakes are a nightmare. They follow a 3-d arc as they approach the rim, which is itself a very complicated 3d surface. Ideally the front edge of the brake pad hits slightly before the rear edge, to avoid squeal... but not too much or it will engage too softly. Even minor wear changes the engagement point. Cables need maintenance, they wear, get kinked, require lubrication, and it's easy to get the tension wrong.

It's all a mess, and even when perfect, and it's dry, not too cool, not to hot, not dusty... they still get worse with every use.

On discs it's more like replace the pads when worn (no adjustments, just remove the pin, pull the old pads, push the cyclinders in, put in the new pads, and put the pin back in). Sure there's occasionally a need for replacing brake fluid and/or bleeding. But generally way less maintenance, and you get like 90% of perfect braking all the time instead of 10-90% depending on temp, wetness, ice, grit, state of tune, etc.

Re:Myths in cycling: wider tires are slower by mymythisisthis on Tuesday June 15, 2021 @07:07AM (#27513582)
What about cable over fluid disc brakes for a commute bicycle?
Re:Myths in cycling: wider tires are slower by sliken on Tuesday June 15, 2021 @10:58AM (#27516444)
I personally think that mountain bikes with slicks make for a great commuting bike. Fast, stable, low maintenance, and shrug off curbs, steps, and potholes. They also tend to be (on average) more upright for better visibility of the road. Also the brakes are available in the up right position, unlike some road bikes. Never know when a car is going to want the piece of road you are on, it's nice to be able to hop onto a curb.

Also MTB's generally accommodate the widest tires, except for fat tire bikes and generally wider tires can be very helpful when commuting for comfort and making things like a random rock or walnut much less exciting when you hit them.

Commuting with rim brakes inevitably destroys the rims, try commuting for 3-5 years then closely inspect your rims, little micro cracks are not uncommon, and will get worse right up until you have a rim failure.

It's also really nice if you do hit something hard enough to knock a wheel out of true, that you still have two working brakes.

Re:Myths in cycling: wider tires are slower by rleigh on Tuesday June 15, 2021 @07:49AM (#27513921)
Once you've used hydraulics, you never want to go back to cable. They are so much better on all counts that the tiny weight gain pales into insignificance.
Re:Myths in cycling: wider tires are slower by analog31 on Monday June 14, 2021 @10:29PM (#27510635)
While I don't dispute this, and I have both kinds of bikes, when I talk to "casual" cyclists who have tried disc brakes, they almost unanimously describe the difference as being like night and day. Perhaps the issue is that they are comparing new disc brakes on good bikes, to old crappy neglected rim brakes on cheap bikes. Still, the difference in popularity is unmistakable.

Myself, I'm not getting rid of my rim brake bikes any time soon, but it's interesting to observe how different people experience cycling.

Re:Myths in cycling: wider tires are slower by sliken on Tuesday June 15, 2021 @02:43AM (#27512079)
I've had top of the line campy brakes, top of the line shimano (dura-ace), and quite a few of the other options.

Do yourself a favor and try out some decent hydraulic brakes. Now only are they pretty amazing, but amazingly consistent. Even in rain, heat, cold, etc. Also it's MUCH rarer to have to undo a brake, just because your wheel went out of true.

Try to track your use, going downhill and hit a puddle, do you drag your brakes? Why? Wait till they grip again? I had no idea I had such habits.

Re:Myths in cycling: wider tires are slower by analog31 on Tuesday June 15, 2021 @02:06PM (#27519195)
Yup, definitely. Agreed about wet riding. The weirdest one was coming out of my cold garage into a hot humid day, and the water condensing on my rims. That's why I say I wouldn't get rid of the rim brakes, but appreciate why they might be in decline.

I've tried hydraulics on friends bikes, definitely nicer, but again not enough to motivate me to switch.

That's how it is with all of these improvements. Someone will always have newer, slicker gear than me, but I keep riding. ;-)

Re:Myths in cycling: wider tires are slower by jmilloy on Monday June 14, 2021 @10:50PM (#27510747)
Yeah, I guess component quality matters, the condiditions matter, rider style and goals matter. It seems like there are plenty of reasons to prefer disc brakes (especially hydraulic), but plenty of others to prefer rim brakes, depending on all of these factors.
Re:Myths in cycling: wider tires are slower by kohlerm on Tuesday June 15, 2021 @01:48AM (#27511752)
For pure road bikes rim brakes are ok IMHO only under certain conditions.e.g. no carbon rims and not much dirt and try conditions. These are not the conditions you will find off-road. Also the difference in wet conditions is IMHo still night and day.
Re:Myths in cycling: wider tires are slower by sliken on Tuesday June 15, 2021 @02:45AM (#27512094)
Heh, have you ridden on road? I find it at least as dirty as offroad. If anything more grit in the winter, any moisture and everything (bike, shoes, legs, socks, etc).

Roads are far from clean, and if anything the debris is more abrasive than you'll find off road. I'd rather have normal dirt than tire and disc dust you'll find on the road.

Re:Myths in cycling: wider tires are slower by ambentzen on Tuesday June 15, 2021 @08:24AM (#27514236)
While in absolute terms rim brakes are probably just as good as disc brakes. The difference lies in the feeling and modulation of the forces.

Also, the disc is a consumable on both types. I have worn down rims to the point where I was scared to use the wheels.

The initial setup can be a bit annoying with hydro discs, but it's a tradeoff I'm happy with.