Singlespeed & Fixed Gear - single speed freewheels with only a front brake?!?

http://www.livejournal.com/community/bikepirates/1376305.html?view=13670961#t13670961

these guys see no problem with running a single speed with a freewheel with only a front brake...someone please help me in educating these guys or people going to get seriously hurt.

btw, my posting on that thread is under the name "velodrone"

i think it is perhaps you that needs educating...ss with just a front brake is a just fine way to ride...as long as you aren't ********...different builds require different riding styles...dude here rides brakeless fix with platform pedals...it's not in what you ride, it's how you ride...front brake? lean back when braking hard...it's easy

-jason

That argument isn't worth it. Say your piece, if people refuse to listen or write your argument off, let it be, life's too short...

Edit: I do see where you're coming from, a fix effectively has a rear-brake, whereas a single-speed does not. However, I ride without handbrakes everyday in the city, rode 40 miles like that today already, nobody's going to convince me that I absolutely need a handbrake, same thing with many of those SS guys and their rear brake...

That argument isn't worth it. Say your piece, if people refuse to listen or write your argument off, let it be, life's too short...

Edit: I do see where you're coming from, a fix effectively has a rear-brake, whereas a single-speed does not. However, I ride without handbrakes everyday in the city, rode 40 miles like that today already, nobody's going to convince me that I absolutely need a handbrake, same thing with many of those SS guys and their rear brake...


word?
you can see where he's coming from? i can't.
A single speed with only a front brake is perfectly fine

I ride ss and can't imagine not having a rear brake. It seems foolish... but then not everything I do is exactly smart. To each there own. If they feel fine without a rear brake let them be. I just don't see the point. Why not just fix it?

Talk about getting worked up over nothing, even on my road bike I rarely use the rear brake. Or when I used to run my Pista on the SS side with only a front brake, as long as everything is in tune, what's the problem? Sounds like someone needs to work on their braking skills.

rode with a freewheel the otherday on my bike...stopped by using the heel of my foot against the rear wheel, it wasn't that hard at all and i live at the top of a hill...


i mean afterall when you can coast you have all kinds of time to think i guess...i dunno if i would make a habbit out of riding without handbrakes with a freewheel but with only a front brake, i mean unless you're going seriously fast downhill with hairpin turns....i don't see what the big deal is...

Uhm, you do realize that a lot of the people from bikepirates also post here...

whatever i'm over it if people have a deathwish that's fine. i was just trying to help, guess it wasn't welcome.

bring on the hurt

Ive been riding a SS roadbike with just a front brake for a couple years.Front brake does most of the work anyway in a hard stop just like any wheeled vehicle.The only time Ive had a problem was when I snapped the front brake cable.You do have to be a little careful over braking when its wet or icy, other than that it works just fine.

a rear brake is not necessary at all.
the front brake provides the vast majority of stopping power.

I recently switched from ss to fixed, but I would've been scared sh*tless if i didn't have a rear brake. Just because of all the hills surrounding my house and stuff, it would've been incredibly dangerous.

The only time Ive had a problem was when I snapped the front brake cable.You do have to be a little careful over braking when its wet or icy, other than that it works just fine.

and that's the *exact* reason why a rear brake is a good idea. well, one of.

isnt any different than ridng a fixie w/o brakes, chain snaps and your looking for a way to stop............

i ride with training wheels in case i pop a tire.
you all are crazy. :D

i think it is perhaps you that needs educating...ss with just a front brake is a just fine way to ride...as long as you aren't ********...different builds require different riding styles...dude here rides brakeless fix with platform pedals...it's not in what you ride, it's how you ride...front brake? lean back when braking hard...it's easy

-jason


your clear and rational logic is missed here in milwaukee, jason.

isnt any different than ridng a fixie w/o brakes, chain snaps and your looking for a way to stop............

exactly

[yoda rhyme]If skilled riders they are fine will they be, skilled they are not will find lessons are free.[/yoda rhyme]

hehe, fake fixies. that part is funny. also the guy that insists they will "eventually endo" if they have nothing to decrease the momentum of the "back half" of the bike :D

It's a sharp learning curve, but IMO..I repeat IMO only a rider sporting a front brake only, fixed or no should be able to skid the front at speed. If you can manage your momentum/weight/braking well enough to lose traction on the front wheel you can brake faster and better than anything on the road. (losing traction is a bad thing I know but it's a good tell that you've got it down for this) If fixed it's complicated a bit cause you've got to contend with the kinetic energy built up in the drive, usually while it's in the air which is the best time to bring the rear full stop. Grab the front, weight back, so close together it's one movement, stop rear while endo (fight the extra kick forward from doing so) and when you bring it back down you are full stop. 25mph to 0 in 2 bike lengths or less I kid you not. Once you've got it down and dislodged your heart from your throat you'll realize it can be done without losing traction n the same space, it's hard to figure out just how -hard- you have to pull is all, how losing traction helped me figure it out.

It can't be good for your ride, less good for you if you fail but I did it in a tight tight spot and decided to examine it afterwards, it works fine. Personally I think it'd make a great event but maybe for someone else, and on nice, nice pavement too if you are going to do it on purpose.

Anywa on topic I rode around freewheel SS at the CMWC to spare my knee, one brake on the front, all I did to my old fixie was have a freewheel slapped on before leaving. Didn't even occur to me that it removes that rear brake and once in NYC I didn't want to go shopping cept maybe for shoes. Rode around just fine bombing traffic. I'm +95% front brake on dry pavement anyway so while I kept it in mind it didnt make much difference.

oh and dont try that at home + I dont know you if you do and **** up your face

I can't understand a word of that, Sam, but the fastest way to stop a bike on decent road surfaces is to sit back behind the seat and grab the front brake hard so as to almost lift the rear. Full stop. No skid, no rear brake, no secret handshake. Sheldon says the same.

Oh, and freewheels with front brake only are ok until the front brake F's up...

i ride my dirt/street moutain bike with just a rear disc brake, but then again, the weight is positioned more to the rear wheel than on a road bike.

" but the fastest way to stop a bike on decent road surfaces is to sit back behind the seat and grab the front brake hard so as to almost lift the rear. Full stop. No skid, no rear brake, no secret handshake. Sheldon says the same."

sheldon's wrong on this one.

I'm alphabetically on bike pirates.

Stevo, how exactly is Sheldon wrong on this one? I'd really like to know, I'm not being sarcastic. Do you have experiences that somehow invalidate what he's saying?

And it's true what I said over there -- my rear brake on my old road bike was broken for months before I noticed because I simply never used it. If you know what you're doing, you can ride with just a front brake perfectly safely.

Yes, you have my full attention. You go first and then I'll explain why he's exactly right.

"If you know what you're doing, you can ride with just a front brake perfectly safely."

i'm not arguing that point; i've ridden a single brake only for the last 17 years, and am perfectly confident i can brake adequately for any situation. Thats doesnt imply that is the ~fastest~ method of braking however. Unless you can manage to brake from (some) speed to zero in exactly zero.zero seconds (which you cant), the added friction of a properly applied rear brake will certainly decrease breaking distance. The moreso the faster youre initial speed. even if the improvement is practically imperceptable, it is faster.

kinda apples and oranges, but many motorcyclists here will testify that they never use their rear brake. ever, because the front is more than adequate. That is, until some emergency situation occurs when the right foot suddeny gets some exercise. Its faster.

The added friction of a properly applied rear brake does jack **** when you are braking hard enough with the front brake to nearly lift the rear wheel. That's the fastest way to stop.

Motorcyclists not using their rear brakes? I hadn't heard of that, but I don't ride motorcycles.

And the original poster in this thread was trying to say that anyone who rides a SS with only a front brake is totally unsafe and will eventually endo, and that is just utter crap.

How EXACTLY did what you say prove Sheldon wrong?

"How EXACTLY did what you say prove Sheldon wrong? "

Sheldon hasnt proven himself right. Nor have you.

I'm afraid you're wrong, stevo.

For any two surfaces in contact, there's a number called the coefficient of friction that defines how resistant to sliding that contact area is. This is a very high number for rubber against pavement, by the way. That's why we make tires from rubber. The amazing thing about the coefficient of friction is that the derivation of this number is completely independent of mass or size of contact area.

In theory, a fully loaded tractor trailer riding on a pair of rubber bicycle wheels could stop just as quickly as a midget riding a bicycle at the same speed on a pair of monster truck tires! In practice, it doesn't work this way.

The coefficient of friction only describes the system undergoing non-destructive frictional resistance. Any system in motion (the semi or the bike and rider) has a certain amount of energy that it must dissipate in order to come to rest. This is dependent on mass.

This energy is typically shed through the heating of the braking surface and frictional heating between the road and tire surface. However when we attempt to shed that energy too quickly by braking too hard, we can stress the system to the point of failure. Occassionally this failure manifests itself as mechanical failure (broken brakes, bent forks, you know) but typically it happens at the road/wheel interface (it also happens at the brake/rim interface pretty much all the time).

When it's the tire that breaks down first, we call this a skid. A skid is not a product of friction, it's a product of the breakdown of the tire. In fact, we end up decelerating at a lower rate when skidding versus proper braking. The peak deceleration comes at the point at which we are just about to enter a skid. If skidding is a problem, we can increase this number by increasing the surface area of the tire in contact with the road. This is part of the reason why semis have so many and so large tires (the other, of course, is load bearing). This increased surface area spreads the stress of the decelerating system across more material and pushes back the point at which we skid.

So what does all this have to do with a bicycle and front brake versus rear brake? Very simply, if we can't throw the front wheel into a skid, adding more rubber to the braking system provides no additional benefit. Now go out, "sit back behind the seat and grab the front brake hard so as to almost lift the rear." In fact, if you put your weight far enough back, you can't endo at all, though that's actually beside the point. The thing you should take note of is that you can't skid the front tire.

So what good is a rear brake? Control. A front brake can make steering difficult and can spill a rider on slippery or loose surfaces. In those conditions, you absolutely want to be able to modulate rear braking in order to keep the rear wheel behind you. By the by, that's why it's dumb to ride a single speed with just a front brake. It works until you need to brake hard into a corner or on a patch of sand. Proceeding in a straight line on a hard dry surface a front brake gives you all the stopping power you can physically use.

"How EXACTLY did what you say prove Sheldon wrong? "

Sheldon hasnt proven himself right. Nor have you.

...

You do realize that you are simply arguing in circles now?

me: Sheldon Brown said this, and I agree.
you: Sheldon Brown is wrong.
me: How?
someone else: Yeah, how?
you: Blah blah blah unrelated to Sheldon Brown being wrong
me: How does that prove he's wrong?
you: Well, you didn't prove he's right!

Seriously. If you want to explain to me how you know that he is wrong, you are welcome to do so. Otherwise you're just being a jerk.

" Now go out, "sit back behind the seat and grab the front brake hard so as to almost lift the rear."

iver never been able to almost lift the rear wheel while doing 35 downhill.

"Proceeding in a straight line on a hard dry surface a front brake gives you all the stopping power you can physically use."

again, I dont argue that.

good description of the braking process Mr Boston

Unless you can manage to brake from (some) speed to zero in exactly zero.zero seconds (which you cant), the added friction of a properly applied rear brake will certainly decrease breaking distance. The moreso the faster youre initial speed.

If you don't disagree with what I said, than what you've written above is false. Actually, it doesn't matter whether you agree, what you've written above is still wrong.

"Seriously. If you want to explain to me how you know that he is wrong, you are welcome to do so. Otherwise you're just being a jerk."

me: Sheldons wrong
you: how?, and you can brake adequately.
me: (not addressing how sheldons wrong), addressing your statement on braking adequetly.
you: hows that prove hes wrong
me (read between the lines) it doesnt, but noones proven hes right, including yourself. (note: Boston did a good job of explaining).
you: your a jerk
me: I must be for actually responding to this last post in this manner.

ok; without addressing the theoretical science as explaind by Mr. Boston, which I cant and wont argue, I think youd be hard-pressed to find someone who can brake faster from excessive speed with a single front brake. Certainly, when your braking slows you to the point that that you can nearly lift the rear wheel, then the rear is providing little, if any benefit. However, it does take time to get to that point. Perhaps BT can provide some more insight on the dynamics during the decelaration process. and perhaps the theory will hold true emprically. Perhaps not.

sorry if i offended your god.

I think youd be hard-pressed to find someone who can brake faster from excessive speed with a single front brake.

Faster? No. But I can brake just as fast.

As those who have ridden with me can attest, it's not uncommon for me to hit the front brake hard enough to lift the rear. This is not for show nor is it by accident. By riding with a front brake for long enough, I've developed a sense of when the rear will lift (and the feedback provided by a fixed drivetrain helps confirm this in action). When braking heavily in an emergency situation, I will brake hard enough to begin to lift the rear. Even under those conditions, the front wheel does not slide.

Therefore a rear brake can add absolutely no additional stopping power.

"Actually, it doesn't matter whether you agree, what you've written above is still wrong."

so the part i'm missing is our focus on 'almost lifting the rear wheel'. I still contend this is not immediate. Either I fail to see, or you didnt indicate, the contribution of the rear brake during the period between initial speed and the point of 'almost lifting the rear wheel'. . It seems to me, that during this periods, the rear brake increases surface area and spreads the stress of the decelerating system across more material and pushes back the point at which we skid. Id like to understand if you can explain further.

also, why do trucks have rear brakes?

If you are applying your front brake to the point of almost doing an endo, then apply your rear brake to get a little more stopping power, your weight is so far forward that the only thing it can do is skid the rear tire. The only reason to ever use the rear brake is if the road is slippery or your front brake fails.

We focus on almost lifting the rear because we want to avoid pitchover. That's all.

I ignored the contribution of the braking rear wheel from the period between initial velocity and pitchover because it's irrelevant. Unless we're skidding it doesn't matter whether we stop with 1 braking wheel or 100.

Trucks have rear brakes because they CAN skid the front tires. Plus, just like on a bike, you want a way to keep the back behind the front.

It's very simple. The maximum possible braking power from the front wheel comes just before it locks. When you're braking this hard, the weight of the bicycle and rider is shifted almost entirely onto the front wheel - the rear wheel is right on the verge of lifting off the ground. In this situation, the rear wheel has almost no traction. Without traction, the rear wheel cannot contribute to braking power - it will immediately lock and skid. In a full-power stop, this is potentially dangerous, since the back of the bike will then move sideways as easily as it move forward. You can test this by locking your rear wheel on a patch of sand. You WILL fishtail. A skidding tire with no weight on it (when you are braking with maximum power on the front brake) will not contribute to stopping distance. From this we can surmise that, since the rear brake is useless in achieving the shortest possible stopping distance, it is unnecessary in normal braking situations. Why get into the bad habit of relying on both brakes when you only need one? I am serious about calling it a bad habit - it can seriously reduce your stopping distance when you need to make a panic stop, and induce a skid or fishtail.

Of course, that said, there are plenty of reasons to have a rear brake:

1. In slippery conditions, when braking the front could mean a skid. A rear skid is controllable. A front wheel skid usually means that you're going down.
2. In rough, bouncy terrain where your wheels could conceivably leave the ground. Applying the front brake here could lock the front wheel, and coming down on a locked front wheel is not good.
3. If the front brake fails, you have a back-up.

For normal riding, that's just about it. The rear brake is a secondary brake only. The reasons for this are not based on mere opinion, but on indisputable, observable fact. If you want to be safest, use the front brake alone as much as possible.

Of course, as with all rules, there are a couple of exceptons:

1. Loaded touring bikes. There is enough weight on the rear wheel of a loaded tourer that even locking the front would probably not cause the rear wheel to lift completely off the ground. In this case, the rear brake CAN contribute to stopping power, and should be used along with the front brake (although it should not be applied as forcefully).
2. Same deal for tandems, probably to an even greater extent. For what it's worth, this is why motorcyclists use both brakes - they're too heavy to lift the rear wheel.
3. This holds true in any similar situation, such as recumbents, pulling a trailer, riding an Xtracycle (if loaded, anyway) or any other bicycle with a longer than usual wheelbase or significant load, or both.

Under normal circumstances, with a normal bike, stick to the front brake. It'll just stop you faster.

EDIT: Just for the record, on any bike with a freewheel, you should always have a rear brake, IMO. It's not strictly necessary, and I've ridden a singlespeed in the snow with just a front brake (it got a little hairy!), but you should really always have a back up. On a pure fixie it's unnecessary, but on anything else I would see it as a critical safety component.

"Faster? No. But I can brake just as fast."

does 'fastest' not mean 'faster than all else'? (Ok, ill concdede that wasnt my inital intent, but it would, make my initial statement technically correct).

seriously, though, how does the friction of the rear affect the dynamics between initial speed and 'nearly lifting the rear'. (edit - i realize you already responded to this)

Of course, as with all rules, there are a couple of exceptons:

1. Loaded touring bikes. There is enough weight on the rear wheel of a loaded tourer that even locking the front would probably not cause the rear wheel to lift completely off the ground. In this case, the rear brake CAN contribute to stopping power, and should be used along with the front brake (although it should not be applied as forcefully).
2. Same deal for tandems, probably to an even greater extent. For what it's worth, this is why motorcyclists use both brakes - they're too heavy to lift the rear wheel.
3. This holds true in any similar situation, such as recumbents, pulling a trailer, riding an Xtracycle (if loaded, anyway) or any other bicycle with a longer than usual wheelbase or significant load, or both.

Only if those bikes are heavy enough and moving fast enough (ie, there is enough energy in the moving system) to skid the front tire. Weight on the rear is beside the point.

"Faster? No. But I can brake just as fast."

does 'fastest' not mean 'faster than all else'? (Ok, ill concdede that wasnt my inital intent, but it would, make my initial statement technically correct).

Who said 'fastest'? I didn't. I said "as fast." That means a properly applied front brake will stop you as fast as you can be stopped and adding in the rear brake will not stop you any sooner. But it also will not stop you an slower either. It does nothing.

By the way, if you could get your weight enough behind the rear wheel that weight transfer under deceleration wouldn't unweight it and cause it to prematurely skid, then it's as effective as the front wheel. So the two can be equivalent. In practice, this is very difficult and impractical.

"A skidding tire with no weight on it (when you are braking with maximum power on the front brake) will not contribute to stopping distance. From this we can surmise that, since the rear brake is useless in achieving the shortest possible stopping distance,"

again, I understand this; ive never argued this point.....but you are not braking with maximum power from time zero. downhill at speed it can take some time to achive max power. It seems to me the added friction/traction of the rear will provide additional benefit. Noone has explained why this doesnt, other than 'its irrelavent'.

I feel thick today; perhaps i need more coffee. perhaps i need to go for a ride with my adequately-equipped single-brake bike and forget about all this nonsense.

I used to ride a BMX bike with front brake only (used to do front wheel tricks). I would never ride a 700c bike with front brake only.

The BMX bike was easier to handle, lower center of gravity, and I could use my feet Fred Flintstone style if I needed to. On a 700c bike, that crap is just crazy. Your center of gravity is just too high over where the friction/pivot point (where the wheel meets the ground) is. Period.

I know a guy who has one of those. I rode it. It sucked. I won't ride that thing.

This will explain very clearly http://www.ebaumsworld.com/videos/snotrocket.html

Who said 'fastest'? I didn't. I said "as fast."

agreed; but the initial post to which i responded said sheldon said 'fastest'. my initial counter also said its not 'fastest', to which i was told wrong.

Regardless, this is getting silly. Boston, i respect your attempts at explaining, though i still feel were missing a piece for the decellaration period. maybe itll come to me during a post-happyhour ride.

again, I understand this; ive never argued this point.....but you are not braking with maximum power from time zero. downhill at speed it can take some time to achive max power. It seems to me the added friction/traction of the rear will provide additional benefit. Noone has explained why this doesnt, other than 'its irrelavent'.

I hit the front brake as hard as necessary to just avoid pitchover. It immediately contributes all the braking force possible. Using the rear brake would not help any.

If the front brake were applied weakly and you wished to stop faster but not apply more front brake, adding in the rear can slow you more quickly. But it's not the inadequacy of the front brake that allows this, it's the rider's desire to not use it.

Only if those bikes are heavy enough and moving fast enough (ie, there is enough energy in the moving system) to skid the front tire. Weight on the rear is beside the point.

Hey, I'm backing you up! Don't get feisty now ;).

Seriously, that was exactly my point - a heavier bicycle can skid the front tire. And I would argue that weight on the rear is not beside the point. If I loaded 25 or 30 pounds into my front panniers, I bet you that I could still lock that wheel. With that same weight on my rear rack, the equation changes. I could probably still manage it (particularly because I'm a lightweight guy), but it would take more power. This is not to try and refute you, just to demonstrate that weight distribution does matter. If I did the same experiment with 50 pounds, I suspect that things would change - I would be able to lock the front with the weight in front, but I would skid with that weight in back. It's an academic point, since loading that kind of weight onto the front wheel of a bicycle alone would be ludicrously stupid, but the point stands - the ability to endo over a locked front wheel has almost as much to do with the rotating mass of the frame and rider as it does with the energy of the entire system. Total energy is most significant, and probably by a much longer shot than I implied in my post, but it isn't the sole factor.

"But it's not the inadequacy of the front brake that allows this, it's the rider's desire to not use it."

okay; we're getting close to the same page....so what happens when the rider ~desires~ to use it, but velocity is such that the leverage of the brakes cannot reate enough friction to ~immediately~ 'almost skid'.

certainly we've all been on some serious downhills where it seems we'd prefer just alittle more leverage.

I don't know about you, but my front brake is setup so that it always has enough power to lock the wheel. Therefore, there is no situation under which I don't have sufficient leverage.

Now there is a theoretical chance that in the teensy weensy split second that it takes me to work my front brake up to "all stop" engagement, I could engage my rear brake for a tiny increase in stopping power.

But to that hypothetical, I would simply say that my theoretically hyper-reactive self would simply apply the front brake exactly as hard as it needs to be at time zero.

"I don't know about you, but my front brake is setup so that it always has enough power to lock the wheel. Therefore, there is no situation under which I don't have sufficient leverage."

not so with me. perhaps therein lies our disagreement. perhaps i need new pads. or a new lever. or a new wrist; but theres been downhills where I KNOW i wouldnt be able to stop immediatly. or perhaps we need to restrict the 'as fast' arguement to only those bikes whose equipment allows for immediate stopping under all conditions. or maybe we've beaten this to death, considering we all agree one brake is sufficient.

http://images.southparkstudios.com/media/images/602/602__image_09.jpg

But yes, if your front brake isn't setup properly, all bets are off.

In fairness "properly" is a bit of a loaded term as what's proper depends on the context. Many people will run their brakes looser for races knowing that they don't need to be able to come to a rapid stop, just scrub speed. It's much more important to not have to worry about grabbing the brake too hard.

"I need to go for a ride with my adequately-equipped single-brake bike and forget about all this nonsense," said stevo.

Hopefully it is raining and a car pulls out just as your front wheel goes over a sewer cap. Then you will learn why you need a rear brake.