Talk:Bicycle brake systems

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1 Airbrake?
2 One handed brakes
3 Friction and brakes...
4 Plagiarism
5 Rearrange titles
6 Dangerous Advice
7 Rim brakes reorg/main article
8 Disc brakes and spokes
9 Braking technique
10 Historic Disc Mounting Standards

[edit] Airbrake?

I was wondering if anyone had devised an airbrake for a bicycle ? I am a complete technical retard, but thought a simple pump when closed off would stop you quite effectively. Brakes at present rely on friction, therefore subject to wear and tear, heat, failure, whereas an air system would be virtually maintenance-free. In the horrible car industry, they have already developed hydraulic systems for recovering the energy used in braking to be recycled as propulsion. However nothing seems to be happening in bicycle innovations at all.—This unsigned comment was added by 62.253.64.7 (talk • contribs) .

[edit] One handed brakes

I removed this section--It appears to me as an ad, rather than real information. One-handed levers have been available for years on tandems, and proper technique (as mentioned below in the article) requires seperate control of front and back. —This unsigned comment was added by 198.208.159.14 (talk • contribs) .

One-handed bicycle brakes are a relatively new invention. (See http://www.brakedirector.com for a picture.) They work by providing equalized pressure to both wheels. This provides for a smooth and complete stop.

This kind of braking system is ideal for those who do not have use of both hands or those who need to have a free hand, and it works well on paved surfaces.

It is not meant for mountain biking or trick riding - those types of riding require finer control over braking.

[edit] Friction and brakes...

User:62.249.214.190 wrote:" Incidentally, a larger pad does not give more friction, but it does wear more slowly ..." It's been a long time since I've done physics, but I'm not sure this is correct. If a pad has more surface area in contact with the wheel it should generate more friction as a whole. Anyone? I'm not sure I have an old physics text to dig up to check this. Wikibofh 20:22, 11 May 2005 (UTC)

A smaller pad builds up more pressure than a larger pad (at the same force). However, other factors apply as well. A larger pad may dissipate heat a little better (this may be an advantage when much energy has to be "wasted", but a disadvantage unter wet conditions - but most heat goes to the disc/drum/rim anyway). Of course there is point where a pad gets too small to allow for effective braking (because it gets ripped apart before it gets a chance to convert kinetic energy into thermal energy). --Klaws 13:22, 18 November 2005 (UTC)

The physics behind this is the force of friction is equal to the coefficient of friction times the force on the surface (normal force). The coefficient of friction doesn't change with surface area and the force is the same whether it is 1 square inch or 10 so the force is the same. Like the above said, there are other factors such as heat dissipation and wear. - Jwink3101

[edit] Plagiarism

Has anyone compared this page at Wikipedia to Sheldon Brown's article about braking techniques?

I've seen better plagiarism in a tenth grader's essay about bicameral legislatures.206.53.17.207 06:11, 18 December 2005 (UTC)

[edit] Rearrange titles

This article is rather haphazardly divided. I recommend that we organize the order of the types of brakes. How do you recommend? Alphabetically? Chronologically? --Adamrush 16:30, 2 April 2006 (UTC)

[edit] Dangerous Advice

The assertion that it is practically impossible to lock up the front wheel when in motion by using the front brake alone is questionable. There have been great leaps forward in bicycle braking in recent times notably the widespread adoption of disc brakes/V brakes that used to be the preserve of higher end bicycles. There are many braking setups that will apply full lock with as little as one finger on the brake lever, so playing down the possibility of going over the bars seems a little ill-considered. —This unsigned comment was added by 217.31.144.38 (talk • contribs) .

I'd have to agree for a different reason. The increasing popularity of front suspension makes going OTB easier than ever--even if one braces oneself properly. However, with unsuspended forks, it's still quite a feat to lock a front wheel with a bicycle brake. --Adamrush 16:54, 6 April 2006 (UTC)

I agree, and I have edited the section to reflect this. From my experience, almost any rider with a V-brake or disc brake system could easily make the mistake of locking up the front wheel and going OTB during a panic stop situation, especially if they weren't familiar with how the bike behaves during very hard braking. -SCEhard T 19:17, 6 April 2006 (UTC)

[edit] Rim brakes reorg/main article

The section on rim brakes needs a serious reorganization or to be moved to its own article. If the former, I propose that the heading "Rim brakes" be replaced with "Centerpull brakes", "Cantilever brakes," "Caliper brakes," and "Rod brakes." Feedback would be greatly appericiated before I throw this article to the butcher. --Adamrush 13:04, 15 April 2006 (UTC)

[edit] Disc brakes and spokes

Can someone clarify this recent addition: Furthermore, a disc brake puts more stress on a wheel's spokes than a rim brake, since the wheel is held only at the hub. Isn't every wheel "held only at the hub", disc or not? The logic here seems flawed. --Ds13 17:10, 11 May 2006 (UTC)

I think that the critical difference between rim brakes and disc brakes, that the addition was trying to convey, is that with disc brakes the torque of braking occurs between the hub and the rim, while with rim brakes the only time torque occurs between the hub and the rim is at the rear hub during pedaling. It is true that rim brakes can work with radial spoke lacing on the front wheel, while disc brakes require cross-lacing (usually 3x). So while the addition was somewhat inarticulately expressed, it is indeed based in fact. Matt Gies 17:25, 11 May 2006 (UTC)

Thanks, that's a great explanation; makes sense. I used your explanation to clarify the article so the question won't come up again. Cheers. --Ds13 19:51, 11 May 2006 (UTC)

I'm curious why you added the "on the front (non-driven) wheel" qualification to radial lacing? Opinions and preferences aside, rear wheels can be radially laced (and even more commonly, half-radial laced on either the drive or non-drive side). Thinking about it, I could probably remove the "lighter" qualification also, since there are coaster-brake equipped bikes that use radial lacing on the rear also. This would usually be done with many more than the usual number of spokes (i.e. heavier), but it's a notable cosmetic trend in bikes. --Ds13 21:16, 11 May 2006 (UTC)

OK, I hadn't seen/heard of rear wheels radial on both sides. I'm actually running a rear wheel with 1-cross on the freewheel side myself right now, just because I was a little reluctant to jump into a radial lacing there at first attempt, but radial on both sides is news to me. You seem to know what you're talking about, though, so I stand educated. Gzuckier 16:25, 12 May 2006 (UTC)

Yes, if you read up on this and talk to builders, there are a lot of conflicting claims. Every combo is out there (some, probably destined to crumple!) Some say "radial lace on the non-drive side for maximum strength" and others say "radial lace on the drive side for maximum strength". They both back it up with their own interpretation of torque and physics. I don't know enough to know who is right, but you can definitely see radial on both sides (usually with high-profile rims). Then there's the 72-spoke full radial scene among low-riders and beach cruisers... Cheers! --Ds13 16:51, 12 May 2006 (UTC)

[edit] Braking technique

"The downhill (gravity-provided) acceleration (while braking) can be assisted by pedalling while front-braking for further stability (this counter-intuitive technique of actively pedalling while braking is akin to "left-foot braking" or "toe & heel" in automobile / motorcycle cornering-braking techniques)."

Does anyone know what this is trying to say? The Heel-and-toe article refers only to setting the throttle while braking in order to facilitate shifting. This can't possible apply to cycling, can it?

The Left-foot braking article refers mostly to controlling oversteer. It also cautions "this technique should not be confused with Heel-and-Toe, another driving technique." Is the author of the above quoted sentence advocating causing the rear wheel to slide "for further stability"?

Are there any references for this? -AndrewDressel 03:51, 3 August 2006 (UTC)

None found, so it is out. -AndrewDressel 12:38, 4 August 2006 (UTC)