mandovoodoo

I've got both calipers from one lever on one of my tandems. Works well if kept calibrated. Otherwise I personally would use the front. That's what I generally use. Never had a problem. But I can see how other opinions would exist and have validity.

Problem with just a rear is that the amount of braking available is highly limited.

But I really like having both brakes available!

Motophoto

If you guys are not using the front brakes, God forbid you ever have to stop fast, even with my fat ass over the rear wheel it takes a long time to stop using only the rear brake. Yes you are right you will never go over the bars due to braking only using the rear brake but you will run off the road at speed or hit unmoveable objects due to carring too much speed you could not scrub off with that little girly rear brake .

EURO

Rear brake = n00b or someone with crappy brakes.

Olebiker

I am not saying that you should only use the rear brake.

Motophoto

I think I see what most people are saying here in their own way......it would be best if you could have both brakes but the front offers the most stopping power . The few that say they only use the rear brake must be joking .

btjzx6rr

the point was that with proper control yes the front brake can lift the rearr wheel, gently ease off a little, back sets right back down nicely, its not an on off switch, i can trail brake(use front brake all the way down to the apex of the turn) the race bike, and the road bike, no big deal, and am no expert at either one. i can also stand both of them on the front wheel if desired.

what i am trying to say is because the front brake has so much potential stopping power, you should not avoid it, but quite the opposite, learn to use it, once you understand the brakes and tires limits then the front brake is a very effective tool, not a death hazard.

Zouf

I believe you need a course in physics.

First: Max brake force from (any) wheel is limited by slip between the tire and the ground. Slip is reached when the braking force is equal to the slip limit, itself directly proportional to the vertical load on the tire. More load = higher slip limit = higher brake force.

Second: brake force, regardless from which wheel it's generated, will cause a pitching moment, and thus will load the front wheel, and unload the rear wheel. Total wheel load (front + rear) will remain equal to the total mass (bike + rider), but the front will load - you have a brake force acting horizontally below the center of gravity, there has to be a reaction somewhere.

Third: Combine #1 with #2, and you get: as the braking force increases, the front wheel loads, and its max brake force increases; at the same time, the rear wheel unloads, and its max brake force decreases.

All the stuff above is not something like an opinion; it's hard solid physics. And you see the resultant of all this in the size of brake discs on cars (often larger in front than in rear), brake discs on motorcycle (dual, larger rotors in front), etc.

True, rear brake will not make you go over the bars, and front brake can. But rear brake max stopping power is limited, and the result once you reach it is a loss of rear wheel traction - not great in a turn, as the skin on my right knee can attest. So yes, the front brake should be used a whole lot more than the rear brake, if you really want to stop that bike as quickly as possible.

Olebiker

Got it.

No problem with that.

That makes sense.

I have no argument with what you have said. I understand all of that.

Perhaps some engineering or physics student can produce an equation to answer this. If I use both brakes, will the rear wheel unweight the same amount as it would if I use only the front brake?

chroot

Your second sentence, in bold, is the definition of unloading the rear wheel. I can't believe you are still arguing.

- Warren

chroot

Newton's second and third laws of motion fully describe the behavior.

You can only unload the rear wheel with the rear brake to the point at which the friction from the brake overcomes the friction from the pavement and the wheel locks up. After that point, the only remaining force is the friction of the locked wheel being dragged over the asphalt. The coefficient of kinetic friction (dragging a locked wheel across the pavement) is much smaller than the coefficient of static friction (normal rolling motion), and thus the skidding, locked rear wheel provides very little stopping power.

You can't go over the handlebars (something which we might be able to call "negative loading," the rear wheel actually coming off the ground) this way, but you can reduce the weight on the rear wheel to almost zero. The front brake can be used to unload the rear wheel even further, until it goes over your head, but that's irrelevant. The bottom line is that, given a specific deceleration, caused by either brake, the rear wheel will be unloaded to the same extent. The difference is that the rear brake cannot provide a deceleration sufficient to throw you over the handlebars, while the front brake can.

- Warren

Olebiker

Using your definition then, when I slam on the brakes on my car and the front wheel slides, it is because they are unweighted. Never mind that most of the weight of the car is on the front tires.

Try this. Walk along side your bike and slam on the front brake. The rear end of the bike will rise up. Do the same thing but clamp down on the rear brake. The rear tire will skid. The rear tire did not skid because any weight was removed from it but because the friction was overcome.

Olebiker

Thank you. That's my point.

chroot

Are you really that stupid, or are you being purposefully obtuse?


Are you trying to educate me? That's so adorable.

- Warren

chroot

No, it wasn't; that was my point. For your reference, your point was:


...which is total bull****, given the same deceleration.

- Warren

Olebiker

Goodness sakes, you're getting all het up. Tell you what, I'll take my 30+ years of experience road riding and continue to brake with both brakes and you can do what you wish.

Zouf

The weight shift depends only on the total brake force, regardless of which wheel generates it.

Cycliste

I think this is the best (only? ) solution on this thread. Install a basic brake lever (flat bar type)on the drops facing back to the existing brake lever and distribute the braking within the four fingers of the best hand.

Being on the right hand-side, his left arm remains available for signaling so that'll work well. My preference would go with leaving the right hand rear brake as is and assign the new lever as the front brake.

chroot

I don't believe I ever told you that you shouldn't use both brakes -- I do. I just took objection to your claim that if you are using both brakes, you don't unload the rear wheel as much as when using only the front brake, because it's wrong.

You have 30+ years of cycling experience, but I have a degree in physics. Who do you think knows physics better?

- Warren

Cycliste

russdaz

some interesting thoughts, the majority are thinking the same ways as me. think i'll be sticking with my current setup right hand front brake.

just a matter to re-adjust and re-gain confidence again.

cycle17

I brake mostly with the front brake anyways. I would say it 75/25 frt vs rear.

dirtbikedude

I have had the front brakes and the rear go out at different times and I have had both go out at the same time on my mtb. The latter does cause me to change my riding habits/style but if I only lose one brake I still ride as normal. On my roadie I prefer the front and on the mtb I prefer the rear but I would not swap the levers just to accommodate not being able to use one hand if it is only a temporary numbness.

As far as I know, the only company that makes a brake system that controls both brakes with one lever is Grimeca and it is only on their hydro. disc systems. You get full power to the front (or rear depending on how you set it up) and about 50% in the back.

DBD

Olebiker

Warren,

Sorry I yanked your chain so much. Once my daughter's wedding is over this weekend and I have a little time to do so, I'll have to do some studying on the physics.

WD_40

When I have to make a panic stop, I use both brakes. I lock up the rear brake (assuming that surface conditions wouldn't make a skid dangerous), and modulate the front brake to get me stopped. I use the locked rear wheel to help me feel the 'float' of the rear end.

As a kid I learned to do stoppies on my BMX bike and various tricks built off of that. Now that I ride MTBs and road bikes, I still practice stoppies. I mainly do stoppies jsut because it's a fun trick, but after hundreds of repititions, it also teaches me the balance points of my bike and how much force I can apply before I go flying.

Last week, a truck pulled out in front of me and without my front brakes, I would have pancaked into it. I was doing a rear-wheel-in-the-air stoppie right up to the truck. Thank God I got it stopped about 3 inches from impact.

People who are afraid of their front brake should go out to a parking lot and get used to it. Start off slowly and practice, practice, practice until you're comfortable using it in a panic situation. It may save you a nasty collision someday.