[Weav]

Hey guys, I just read an article in Bicycling magazine where someone stated that the proper way to brake on a road bike is to use 60% front brake. And if you're descending then use more power as needed on the fronts. I have always used my rear brake for most of my braking as it seemed to me like the safer way to slow my bike down with no risk of sliding forward or worst case going over the bars if you slam on the fronts. Proof of this is that I wear my rear pads down twice as fast as my fronts.

Any opinions?

 

[bikebum1975]

Yep front braking has the most power. Just takes a little getting used to it getting over the fear of flipping over the handlebars if you are new to them. I usually use my back break to feather off speed comb the 2 brakes when going really fast. Play with them find out what works for you just don't lock up the front brake

 

[Dubgurl]

This is true. If you notice your car will wear the front breaks down much faster than the rears, and your front brakes are much bigger than your rear brakes. There's other reasons than this but the reason I know of is because if you lock up your rear brakes and not your fronts, the back part of your vehicle (car, bike, train, whatever) will not be decelerating as quick as the front. The reason is now the back is going to try to pass the front and making the vehicle more unstable. The opposite is true if the front locks and not the back, the front of the car is going to try to pull away from the back, you obviously have no steering, but you won't suddenly be facing the wrong way, which is bad in a corner but it's quickly and easily corrected by releasing both brakes then starting the same method of braking again.

Obviously this is nearly obsolete on cars because of anti lock brakes, but I haven't seen a bike with ABS yet (bonus points to anyone who can find one lol)

 

[qmsdc15]

Sheldon Brown's advice on braking is well worth reading. Click on underlined text for link.

Quote from the link "The fastest that you can stop any bike of normal wheelbase is to apply the front brake so hard that the rear wheel is just about to lift off the ground. In this situation, the rear wheel cannot contribute to stopping power, since it has no traction."

 

[LarryM]

To stop real quick, shift your weight back and apply both brakes ... with more pressure on the front brake than the real. If the rear wheel starts to lift or skid, ease up on the front brake until it settles down. A skidding or lifting rear wheel acts as an anti-skid indicator.

Here is a good video on how to stop quickly from IPMBA
[ame=http://www.youtube.com/watch?v=z820UnNKVHc]Maximum Braking (IPMBA) - YouTube[/ame]

Here is a good description of the quick stop from the League of American Bicyclists web site League of American Bicyclists * Tips and Techniques

Photo of an officer executing a quick stop.

 

[Xela]

Cars are usually set up with front brake bias. This is because during braking, there is a load transfer to the front tires meaning the front brakes are the bigger component of your stopping power. Also, as the load is transferred off the rear, they are more likely to lock, so you actually want less braking back there. The tractive force of the tires is a function of the normal force (or weight that is pushing it down) on each tire. The more normal force, the more tractive force available to an extent.

Tires have what is known in classic vehicle dynamics as a friction circle, thought data shows it's never truly a circle, which they have to operate in as shown below in the generic example which I took from driftingstreet.com:

What the circle demonstrates is that if you ask a tire to do either pure acceleration or pure braking by either spinning the tire or locking the tire, there is no traction left for cornering. This is what Dubgurl was referring to. Lock the rear first, it's easy to spin-out. Lock the front, you lose steering.

However, as Larry pointed out, we can influence the weight transfer on our bikes by shifting our body weight. Without shifting our weight, the rear brake could easily lock as the load is transferred to the front due to the reduction in normal force. By shifting weight, we can more heavily brake the rear without locking it while also applying heavy front brakes.

 

[photosbymark]

Locking either is bad news. As far as that pic above goes it would really a bummer if you lock your elbows and knees too for that matter. Get in that position and apply the brakes and the bike slows down. Mr Newton says an object in motion will remain in motion unless acted on by an outside force. Your body is moving, but the braking force is applied to the bike. Unless you have parts of your body that are secure which in a sense makes you a a part of the bike, the body will keep moving. Guys look where you would hit.

Now just from a common sense red neck perspective, if you really NEED to stop that fast one of two things has likely happened. 1. Someone else made a mistake. In that case the surprise factor, the realization of just how fast you need to stop, the reaction time needed to not only hit the brakes but move the body into such a position to save a few feet. The time needed to go through all those processes is likely take most of advantage away from a slightly shorter stopping distance.

2. You made a mistake. You became complacent. You lost concentration for a moment and didn't keep fully aware of what is going on around you. From riding too fast in a very congested area to not watch to see if the other cars are respecting your position on the road, awareness keeps one from needing to stop that in the first place. Yet it also makes it more likely that you could pull the technique off because you are not surprised by the need.

Motorcycles going at higher speeds often make the choice to lay the bike down rather hit something solid with a bike. Road rash is far better than a solid impact to the head. IF you attempt the above technique and it fails, you still can't stop and you then still hit something, it isn't going to be pretty. Going down isn't always the worst thing that could happen.

 

[LarryM]

I just noticed that the photo of the LEO quick-stopping is displayed on theTwoSpoke Home page today (10/27/2011). A few more comments on the technique seem appropriate.

The best video I've seen about the quick stop is the one from IPBMA that is embedded in my previous post. The best text description I've seen is in John Allen's excellent booklet, Bicycling Street Smarts, which is available on line as well as in print. His quick stop discussion is at Bicycling Street Smarts, Chapter 6: Using your Brakes

Like any emergency maneuver, it should be practiced until it becomes ingrained in muscle memory so it can be executed without having to think about it. Shifting weight back and down while modulating the front brake to avoid skidding or lifting the rear wheel pays off in a substantial decrease in stopping distance. In a real emergency, just inches can make the difference between a good story to tell and a serious injury.

Larry

 

[BeginnerCycling]

Sheldon Brown's advice on braking is well worth reading. Click on underlined text for link.

Great site for advice -- I just wanted to point out that folks should read down through the "When to Use the Rear Brake" section too -- the rear brake comes in handy when traction is bad (wet, gravel) and when turning.

 

[TxCyclist]

Great site for advice -- I just wanted to point out that folks should read down through the "When to Use the Rear Brake" section too -- the rear brake comes in handy when traction is bad (wet, gravel) and when turning.

Sheldon Brown was the standard. I still visit his site from time to time.

 

[bikebum1975]

Sheldon Brown was the standard. I still visit his site from time to time.

Think he pretty much still is even though not with us anymore.

I pop on there from time to time myself. Some great reading there

 

[photosbymark]

IF there was one cyclist I could meet that had already passed on, I think it might be Sheldon. One thing I always respected about his writing is that he was pretty clear when he was presenting fact, and when he was presenting opinion. Even if you didn't agree with his opinion, you would be well advised to consider it very closely and think on the logic. His braking article was a classic example. His front braking procedure was spot on with the facts. He laid out his logic why you should brake that way. Its sound. Yet if you have no need to really stop that fast, is it really that important to front brake all the time??? Probably not. He is right that max braking is just before the rear wheel starts too lift. Yet if you go too hard and the rotation starts, you only have a split second to make that correction. How many would react to a rear wheel rising while trying to make an emergency stop by releasing pressure on the front brake? What if it is that time the rear brake decides to fail? Even if you can do it in training, can you still do it when you are trying to stop before you hit a truck and its a surprise? It's my opinion its almost always better to hit something in control than out of control. Would it be better to hit that truck with the front wheel being able to take some of the impact and absorb some of the energy, or go over the bars and hit it with your head? Can the stop be done in a straight line? Just how well does a car turn under heavy braking? Not very. Are you better off to accept a long stopping distance for the ability to turn and miss things?

Using his technique might be the difference between hitting that truck or not, IF its done perfectly when you can do it when you are totally surprised. It might save you and the bike. Be just a little off and it could make things worse. Fact is that you won't know till you fact that choice and when you do you still won't know till after the fact. Hopefully its a choice one never has to face, but if you do you are more likely to make a better decision from having read Sheldon's writing. How close you push it to the absolute braking limits he describes is up to you. An old aviation saying I think applies here, "A superior pilot uses his superior judgement to prevent the need of his superior skill." Many times anticipation can avoid the need for that superfast stop in the first place. Doesn't mean you don't need to know and practice the skill.

My recumbent would take a great deal to go over, and with its weight distribution I am not sure its got enough front braking power to throw me over those bars. Yet its Sheldons way of writing that gets me to really stop and think. I'd like to think he would take that as the highest praise.