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Discussion Starter #1 (Edited)
This was originally going to be in response to some other thread about gimping the rear rotor, where demented and slugger were getting ripped trying to explain this, but I see so much misinformation on this I wanted to make it a new one.

Let me start with this. The rear brake is not useless. However, I'm going to attempt to prove that constant pressure on the rear brake throughout deceleration cannot be the fastest method of stopping on any vehicle light enough to do a stoppie (a technical term).

Pitch, or movement forward and back of the chassis, is a direct function of acceleration (meaning change in velocity, speeding up or slowing down) and nothing else. In fact, if you were to only use rear brake, the bike would still pitch forward--that is until the rear wheel came up enough to lose traction and skid, which wouldn't take very long. So if your rear wheel isn't off the ground it might feel nice and comforting mashing on all kinds of brake levers, but you aren't stopping faster. Front brakes on bikes and cars and whatever don't happen to be stronger, they are made stronger because that's where the weight transfers. In fact, if cars were light enough to do stoppies, you would not need rear brakes on them either for straight line stopping. Even if you didn't have a suspension to compress and the rear doesn't lift, the front tire itself would flatten and does, increasing its contact patch while the rear equalizes into it's natural toroidal shape while lifting, providing almost no contact/friction.

Now, there is a case for using the rear brake initially while there's still contact pressure on both tires, and progressively less until the front forks are loaded, which will in fact result in the shortest possible stopping distance. But after that short period your rear tire is in the air (or because of your balance still on the ground but weightless and thus nearly frictionless) and if it's not you are not slowing down as fast. That's is not a debate. Please call your high school physics teacher if this part doesn't make sense. Now let's forget about what brakes we're using for a moment. Both act on the single body that is the motorcycle. Any braking from anywhere has an effect on body pitch. Therefore whatever combination of brakes pitches the bike enough to lift the rear wheel is maximum braking. And what combination of brakes do we use to lift the rear wheel? Anyone? Front, front and more front. If you still insist applying rear brake constantly through deceleration is best please explain how you're able to slow down as fast, or make any angular velocity change quickly, without a pitching or rolling effect. Because this would solve all vehicle dynamics issues, including cars' body roll through turns which engineers have been wrestling with for a 100 years, resulting in variable active suspension and whatever crazy technology.

Let me put it one other way. When drag racing, would you get off the throttle when you feel the front come up so that the bike was securely loaded on both wheels? Of course not! Because then you're not full throttle and accelerating as fast. In fact common drag practice is to balance such that the front is about an inch off the ground through the whole pass. Why, again because pitch is a direct consequence of acceleration and that's where the pitch will be when you are at the maximum.

If nothing else, for ya'll with the "but fast racers do it like this" argument please youtube some Rossi videos, I've seen several shots that show his rear wheel airborn all the way to corner entry. Did he use rear brake when initially loading the front? Or in other special cases? Maybe, but that's it. Unless of course he doesn't like the gyroscopic stability of his rear wheel spinning.

Lastly, all of this doesn't even take into account the dangers in overusing the rear brake, and that most riders out there are not skilled enough, including myself, to properly roll the rear brake for maximum stopping (which people point out is technically the fastest). So I didn't write this to piss anyone off, but really I'm tired of reading about so many crash boom bang stories about people locking up the rear with the good intentions from their MSF instruction, and people still defending it as best practice in an emergency situation. I'd much rather read about someone who dropped their bike after coming to a complete stop untouched using all front brake (who of course got flamed) than someone who slid out the rear at 30mph before they were even close to a car. Is that worth the extra 5, 10% braking when, and only when done perfectly?

So flame this if you want, but it wouldn't make it an argument, it's not.
 

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lots of riders develop rear braking skills from motocross dirt riding (and supermoto), which they then incorporate into Superbike riding.

While not the best way to stop, it's certainly useful.

Using the rear brake to point the bike in a turn is a common technique. The lesser braking power of the rear brake allows a rider to tuck (or compress) the front suspension slower than you would with the front brake....while allowing for less grip exhaustion.
 

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Discussion Starter #3
lots of riders develop rear braking skills from motocross dirt riding (and supermoto), which they then incorporate into Superbike riding.

While not the best way to stop, it's certainly useful.

Using the rear brake to point the bike in a turn is a common technique. The lesser braking power of the rear brake allows a rider to tuck (or compress) the front suspension slower than you would with the front brake....while allowing for less grip exhaustion.
Yeah, I'm not disagreeing with any of that. I came from dirt too. There's plenty of trick sh*t you can do with the rear brake. I'm just talking about what some people are saying about max. straight line stops.
 

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I tend to only use the rear brake at all only if i need maximum stopping force in a straight line
 

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max straight line stops? ah.

Well obviously the fastest way to stop will be to brake as hard as possible before losing traction of either wheel.

If you can use the front brakes hard enough to lift the rear even a few mm off the ground, without losing front wheel grip....then yes, at that point in time, the rear brake is useless.
 

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i havent ever done a stoppie yet, have tried to do some on purpose, but couldnt

in terms of needing to stop so quick, i have been able to do so w/o doing even a small stoppie.... so i guess the big thing that riders need to get used to (myself for sure when i was a true noob) is that u can def grab more front brake than u think if u need to stop really quickly
 
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Neither KS or I where getting ripped on this topic, because you where failing to listen to our arguments and where going off in another direction. Let me get one thing straight, for the last time. My argument, was the rear being useless during emergency situation braking. I never once said that throughout all braking, the rear is useless, but with a supersport, unless it's a time when you just don't really want to slow fast and start braking far before you really need to stop on the road, the rear brake wont do much at all but cause problems because of how strong the rear is and how quickly the front brakes can load.

That aside, you posted a good thread. I too am sick of reading threads in CBB where people crash because they lost the rear, but come out and say "I had no choice but to lock the rear" when someone cuts them off, which is where my argument of the rear being being useless in emergency braking comes in. The majority of people just generally do not know how to ride and just go to full braking on front and rear while trying to do all other sorts of stuff, even if it is a simple situation where a twist of the wrist and turning to the side could have avoided the whole situation. Sadly though, most of the time, people are doing what they learned from the MSF courses.

I'm not saying all MSF courses are the same, but the one I went to, was not the best at all. For the maximum braking distance test, they where telling people to grab as much front brake and use as much rear brake as possible. Everyone but 4 of the 18 locked their rear. Myself, 2 other people who ride sport bikes, and some guy who weighed 300lbs where the ones who didn't lock the rear, because of the following. The test was to get the maximum stopping distance, within 20', from 15mph, at a given point, and everyone was told to get on both brakes at the same time as hard as possible. People where locking up the front and rear nonstop because of that. The 300lb guy didn't lock them because, well, he weighed too much, lol. The three of us who rode sportbikes only used the front brakes, and had the shortest stopping distances, because well all know that sliding tires don't stop fast. They where even saying the same thing during the ECR class when I was watching, which was funny, and scary, because I watched a guy get ass raped by his gixxer while sliding face first on the ground.
So, it's not always just the people causing the braking problems, but also some MSF courses.
 

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Discussion Starter #8
Neither KS or I where getting ripped on this topic, because you where failing to listen to our arguments and where going off in another direction. Let me get one thing straight, for the last time. My argument, was the rear being useless during emergency situation braking. I never once said that throughout all braking, the rear is useless, but with a supersport, unless it's a time when you just don't really want to slow fast and start braking far before you really need to stop on the road, the rear brake wont do much at all but cause problems because of how strong the rear is and how quickly the front brakes can load.
Dude what? That's what I'm saying. :all_cohol
 

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yeah.

MSF course failed horribly in that respect.

Braking was certainly not their strongest topic.

You sit back, apply progressive pressure on the FRONT brakes.
 

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im a firm believer in rear brake control. I didnt read the whole thread but fron riding dirt bikes like the other guy said its natural to use both sets. I wear rears quick espically when doin a wheelie cover that brake !!!
 
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Dude what? That's what I'm saying. :all_cohol
I know, just wanted to make it clear. Sorry. I haven't been in the best of moods lately.
yeah.

MSF course failed horribly in that respect.

Braking was certainly not their strongest topic.

You sit back, apply progressive pressure on the FRONT brakes.
MSF failed more then in braking. They where saying my form was horrible when taking turns because I was leaning off the seat and was not keeping my back straight inline with the bike and legs pressed up against the tank.
They also tell you to use the front brake in a turn if you see a hazard in your way, that clutches last for ever so use it and slip it all you want, and...get this. "Are you really going to wear all of that for the course?" to me as I am putting on a textile jacket, body armor, full GP gloves, 3/4 cut boots, and knee/shin pads.
 

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ok. A little overkill on the protective gear. They expect you to go no faster than 30 mph at any time during the course. I'm a gear nazi....but uh.....no.

Leaning off the seat? You kidding me? This isn't racing school @ Jennings GP, it's an MSF course. You don't need to move an inch off the seat doing a 15mph turn. Just handlebar input and some body lean. See my avatar? 100mph left hander onto the straight at Summit Point Raceway Shenandoah. I had to "lean off the seat" just a little bit.
 
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ok. A little overkill on the protective gear. They expect you to go no faster than 30 mph at any time during the course. I'm a gear nazi....but uh.....no.

Leaning off the seat? You kidding me? This isn't racing school @ Jennings GP, it's an MSF course. You don't need to move an inch off the seat doing a 15mph turn. Just handlebar input and some body lean.
I was actually doing over 30. I couldn't help it, lol.

I watched my dad tip over, doing 2 mph, on a bike and spend 10 days in ICU and came within 30 seconds of dying. Gear is my friend, regardless of speed.
 

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That and MSF teaches cruisers too, and i haven't seen one of them lift the back wheel off the ground yet...
 

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I'm not sure if it's the exact same thing, but Ben Bostrom did that all the time. His bike looked like a swimming fish every time he entered a corner.
I don't think that is because he's using his rear brake. I think that is because his rear end is basically up in the air flopping around due to so much pressure on the front brake. Lots of guys do it.
 

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Not to keep off topic here, but...

All this MSF talk's kinda gettin me worried. I take my course on the 19-20. I've ridden my bike for about 150 miles now, on road. I'm no expert at all, nor do I know 10% of the techniques and tricks I need to know. But I feel I have a very basic, fundamental understanding of riding my bike. However, I don't know the "braking techniques" I keep hearing so much about. "What do you do if someone pulls out in front of you?", and things like that.

Now with what you guys are saying, I'm kinda worried about this course. Not only for looking like a dumbass, but for my safety also. No I do not know how to stop instantly. My instinct is gonna tell me to use the front brake progressively because that's all I use when I ride. But if they're telling me something else I think I'm gonna think too much about what I'm doing and screw up. I don't wanna get thrown off the bike, nor do I wanna fail the exercise b/c I'm being overly cautious or over-thinking. Any advice?
 

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So I didn't write this to piss anyone off, but really I'm tired of reading about so many crash boom bang stories about people locking up the rear with the good intentions from their MSF instruction, and people still defending it as best practice in an emergency situation.
I believe that you're not understanding how many people were taught to use their rear brakes on the street. My MSF instructor preached using as much rear brake as possible, without locking, and if you happen to lock it up release and re-apply. And that 10% of braking rule applies even if you only use it for a small amount of your total braking. Just because you release pressure on it, doesn't mean it's braking force is nullified.
 

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Discussion Starter #20 (Edited)
I believe that you're not understanding how many people were taught to use their rear brakes on the street. My MSF instructor preached using as much rear brake as possible, without locking, and if you happen to lock it up release and re-apply. And that 10% of braking rule applies even if you only use it for a small amount of your total braking. Just because you release pressure on it, doesn't mean it's braking force is nullified.
I'm not 100% sure what you're trying to say at the end. But you're right, using it to begin a braking maneuver is what contributes the 10% overall. Not arguing with you there. Just saying thats a very hard thing to do right in an emergency for most riders including myself, and most dont even know about that whole practice. My point is that I don't think that 10% is worth the risk of losing the rear. Whether instructors intend it or not, a lot of riders have it in their heads "mash on both brakes as hard as you can and pray." Especially teaching it with attitudes like "as much rear brake as possible." That skips several very important but's. For instance, "let off and re-apply rear if you lock it up?" I really cannot understand that kind of advice, especially for newer sportbike riders. So what about if your rear starts to slide out? You're supposed to let it hook up again so you've got a chance of a nice high side? That skips a lot of important details like counter-steering into the skid to get the bike upright again first before I'd ever let off and re-apply rear brake. But I guess flipping through the air is a more entertaining way to go out. My point is, in theory, or in the right situation with an incredibly good rider, yes the rear brake in a threshold stop will get you that 100% of a sport bike's stopping potential. Or, you can learn to use and rely on your front brake to its fullest, which accounts for all of your stopping power after .5 seconds anyways, once the front forks are loaded, and not have to worry about sliding anywhere.

The more I think about it, there really needs to be a sportbike oriented MSF course. So much of it is critical for every new rider, and yet so much of it is not applicable, or at least incomplete when it comes to sportbikes.
 
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