Trail braking?

[No Worries]

As a scientist, why would I want to put braking and steering forces on only one tire by using only the front brake? I can split these two forces to two tires by using both brakes.

I hardly ever use trail braking going up a mountain. But coming downhill, I use it on almost every tight corner. I brake with both brakes before the turn, keeping them on into the apex of the turn, and accelerating out smartly. Smooth, quick, and safe.

Do you know what a switchback is? Some call it a hairpin turn. You turn 180 degrees, just like a U-turn. Lookout Mountain has at least six switchbacks. You have to brake from 50 to 15mph. And most of them are blind. You don't jam on the brakes like a racer. You squeeze both brakes smoothly before and half-way through the turn.

[The Awesome]

Originally Posted by No Worries

As a scientist, why would I want to put braking and steering forces on only one tire by using only the front brake? I can split these two forces to two tires by using both brakes.

That depends on the bike you ride. If you ride that thing in your avatar, you are probably better off using both brakes. If you ride a modern sportbike, you will find that proper application of the front brake will unweight the rear wheel to the point that it offers no straight line stopping power. I ride my dad's R1100R BMW from time to time, and no matter what I do I can't make it even begin to lift the rear wheel. The way the front suspension is designed combined with the geometry of the bike make it impossible to lift the rear, as it will lock up the front instead when you reach the threshold of the tire. In cases like this, both brakes must be used for maximum stopping potential.

[Amber Lamps]

Originally Posted by The Awesome

That depends on the bike you ride. If you ride that thing in your avatar, you are probably better off using both brakes. If you ride a modern sportbike, you will find that proper application of the front brake will unweight the rear wheel to the point that it offers no straight line stopping power. I ride my dad's R1100R BMW from time to time, and no matter what I do I can't make it even begin to lift the rear wheel. The way the front suspension is designed combined with the geometry of the bike make it impossible to lift the rear, as it will lock up the front instead when you reach the threshold of the tire. In cases like this, both brakes must be used for maximum stopping potential.

Mr Awesome , sir, we were taught to apply the rear brake first and then the front to avoid that problem anyway... I think. Try it and tell me if I'm right that the forward shift isn't as drastic. BTW I'm sure that you are right.

[101lifts2]

I do on the track and on the street..but the street is more if you haulin ass around a sweeper and there is a line of cars as you crest the turn doing 1/3 your speed.

If you have sticky race soft tires, you would be amazed at how much force the front tire can take on the brakes in a turn.

[The Awesome]

Originally Posted by TIGGER

Mr Awesome , sir, we were taught to apply the rear brake first and then the front to avoid that problem anyway... I think. Try it and tell me if I'm right that the forward shift isn't as drastic. BTW I'm sure that you are right.

Was this taught in the context of racing or street riding? As I said before, I never use the rear brake, so I'm not a good person to ask about what context to apply it. In straight line braking in a performance riding context, the problem I see with that is you are creating a dead spot between closing the throttle and applying the front brake if you do it that way. Even the smallest window of time without using the front will ruin your chances at hitting a correct braking point. You would have to start braking sooner than desired if you wanted to apply the rear and then the front in sequence.

Another problem I have experienced when playing with the rear brake in straight line stopping is that when the rear becomes unweighted it seemed to be harder to control the bike and keep it stable without the rear wheel spinning free. I would assume this is a result of a spinning rear wheel creating a gyroscopic effect. I also noticed that in situations where I would apply a little more front than desired and actually lift the rear completely, it would tend to want to skid abruptly rather than slide smoothly when I set it back down. This would make it much harder to hit the turn in point that I wanted, because I would be fighting to settle the bike down deep into the corner. All of this is just personal observation and interpretation, so I could be completely off base with that. My experience with the rear brake is minimal, and the experiences I had could easily have been a result of riding technique or bike setup problems that I overlooked at the time.

Originally Posted by shmike

Awesome, good explaination and pic. That is some serious front-end dive though. I have always had mine set up to leave 10-15mm of travel at full stop.

I thought the same thing the first time I saw pictures of myself on the brakes. I asked my suspension guy about it and he told me that unused travel is wasted travel. Just make sure that for any given track you don't ever bottom out. If you do, changes need to be made to accommodate.

Originally Posted by No Worries

Not only am I a scientist, but I'm a realist too. Compare the stopping distance of cruisers with sportbikes in the magazines. The cruisers weight 200-300 pounds more, have smaller rotors, and touring tires, but stop in the same distance. If they put sticky tires on the cruisers, they would stop quicker. Could it be that the cruiser has two wheels on the ground while stopping?

I don't read bike magazines, but I have never ridden nor seen a cruiser that could stop anywhere near as quickly as a sportbike.

Originally Posted by No Worries

If I was on a modern sportbike braking so hard for a tight curve that my rear wheel was off the ground, I don't think I could successfully make the turn.

The faster you want to go, the more skill is required.

Originally Posted by No Worries

Sooner or later, someone from TWF will make it out to Denver and will want to ride Lookout Mountain. I want them to know how to ride it quickly and safely.

Unless Lookout Mountain has a bunch of Indiana Jones-esque booby traps, I'm sure it's no different than any other road. The same riding principles will always apply.

[Amber Lamps]

Originally Posted by The Awesome

Was this taught in the context of racing or street riding? As I said before, I never use the rear brake, so I'm not a good person to ask about what context to apply it. In straight line braking in a performance riding context, the problem I see with that is you are creating a dead spot between closing the throttle and applying the front brake if you do it that way. Even the smallest window of time without using the front will ruin your chances at hitting a correct braking point. You would have to start braking sooner than desired if you wanted to apply the rear and then the front in sequence.

Another problem I have experienced when playing with the rear brake in straight line stopping is that when the rear becomes unweighted it seemed to be harder to control the bike and keep it stable without the rear wheel spinning free. I would assume this is a result of a spinning rear wheel creating a gyroscopic effect. I also noticed that in situations where I would apply a little more front than desired and actually lift the rear completely, it would tend to want to skid abruptly rather than slide smoothly when I set it back down. This would make it much harder to hit the turn in point that I wanted, because I would be fighting to settle the bike down deep into the corner. All of this is just personal observation and interpretation, so I could be completely off base with that. My experience with the rear brake is minimal, and the experiences I had could easily have been a result of riding technique or bike setup problems that I overlooked at the time.



I thought the same thing the first time I saw pictures of myself on the brakes. I asked my suspension guy about it and he told me that unused travel is wasted travel. Just make sure that for any given track you don't ever bottom out. If you do, changes need to be made to accommodate.



I don't read bike magazines, but I have never ridden nor seen a cruiser that could stop anywhere near as quickly as a sportbike.



The faster you want to go, the more skill is required.



Unless Lookout Mountain has a bunch of Indiana Jones-esque booby traps, I'm sure it's no different than any other road. The same riding principles will always apply.

Street riding for sure! In fact this was the much touted MSF course I took in 1984... I had already "learned" to ride using cruisers and enduro bikes.

I'm sorry NW but when the racer guys, like Awesome and CEO, bust on you, I can't help but laugh my ass off!

[shmike]

Originally Posted by The Awesome

I thought the same thing the first time I saw pictures of myself on the brakes. I asked my suspension guy about it and he told me that unused travel is wasted travel. Just make sure that for any given track you don't ever bottom out. If you do, changes need to be made to accommodate.

I guess the logic in leaving a few mm to spare is making sure you don't bottom out. If you can get to full travel on the brakes that leaves no room left to absorb any bumps on corner entry.

Total agreement on all other points. There must be a reason we ran the same number.

[shmike]

For those that don't understand the concept of loading the front forks with the brakes and keeping that load while cornering, I found a decent pic of tipping it in.

In a sequence this shot would be about 50-100 feet after Awesome's pic.

As the braking forces fade the lateral forces take over:

[shmike]

Originally Posted by No Worries

As a scientist, why would I want to put braking and steering forces on only one tire by using only the front brake? I can split these two forces to two tires by using both brakes.

I hardly ever use trail braking going up a mountain. But coming downhill, I use it on almost every tight corner. I brake with both brakes before the turn, keeping them on into the apex of the turn, and accelerating out smartly. Smooth, quick, and safe.

Do you know what a switchback is? Some call it a hairpin turn. You turn 180 degrees, just like a U-turn. Lookout Mountain has at least six switchbacks. You have to brake from 50 to 15mph. And most of them are blind. You don't jam on the brakes like a racer. You squeeze both brakes smoothly before and half-way through the turn.

Typical scientist. You're only looking at the hypotheticals on paper without considering the real life experience.

Once the back tire is off or skimming the ground it offers little or no stopping force.

"Jam on the brakes like a racer."

Awesome, good explaination and pic. That is some serious front-end dive though. I have always had mine set up to leave 10-15mm of travel at full stop.

[Amber Lamps]

Originally Posted by shmike

Typical scientist. You're only looking at the hypotheticals on paper without considering the real life experience.

Once the back tire is off or skimming the ground it offers little or no stopping force.

"Jam on the brakes like a racer."

Awesome, good explaination and pic. That is some serious front-end dive though. I have always had mine set up to leave 10-15mm of travel at full stop.

I'm not as cool as you guys but if I set me bike up for 10mm, I would lose the front guaranteed!!! You must have the brake control of a GOD!