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Old 03-31-2012, 09:18 PM   #31
WARRIORPRINCEJJ
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Quote:
Originally Posted by syaufu View Post
Take a class with Jimmy Lewis..one of the most accomplished riders around..and you will be taught to break the way it was described...butt off the seat ...I think I will follow his advise before most anybody else on this forum..bj

The next time one of us has to make an "emergency stop", in the dunes, we'll keep that in mind...


.
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Old 03-31-2012, 11:15 PM   #32
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when i did my bike test i was told to use the front 1st to get a much speed of then put on the rear so you have both brakes on

in the WET you should put the rear on 1st than the front.
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Old 04-01-2012, 12:42 AM   #33
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Back in the day (when I was 19 and immortal) I owned a 550 Seca, with about 40 lbs of the stock mass "missing" and a few extra horsies added. Because I was a special brand of stupid and was aiming for a REALLY spectacular death, I used to practice panic-braking on my single-disk front, pushrod-drum rear bike from 190ish kph every time I approached the entry to my trailer park (heh) off the highway. You'd be amazed how much energy a single disk can scrub off.

I'll say one thing about stopping hard on pavement: you want your ass on the seat to help keep you from going right over the fucking bars*. When you're crash-stopping so hard that each downshift leaves a 2-foot black dash on the road, you begin to get a sense of how hard you're working to keep your nuts out of the instrument panel. I may only weigh 130 lbs, but there's a pisspot full of kinetic energy in ANY mass that's traveling at high velocity.

Y'all go ahead and stand up at highway speed when you realise that you _need_ to lose 50 kph to avoid someone else's stupidity. Hope you've got strong arms for when you realise your entire body is headed forward at your original, pre-brake velocity, and your ass is no longer helping to hold you in place.

It took me a while to figure out the fine diamond pattern on my new bike's seat. Then I realised my ass wasn't trying to move when I took it out and flogged it hard. Butt-tread!

By the way, I want to see Jimmy ride on the street. Anyone want to start a forum pool on where his butt is when he tries to stop on pavement?

*Okay, I've never ridden a KLR. Are they like riding an oil tanker? Even the old CR 80 I learned/almost died** on would endo if you asked it to.

**That bike was AWESOME.
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Old 04-01-2012, 02:02 AM   #34
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Originally Posted by dwoodward View Post
Anyone besides me laughing? I can, with good tires, clean pavement, and a lot of luck, stoppie my KLR... about six inches.

Don't HIT the brake- squeeze it. I don't know WTF you're doing that the topbox is being a problem, but whatever it is, is wrong.
Let them flog me as well. I'm laughing with you. I get the best results out of students when it is raining. On the other hand I get the best laugh out of so called seasoned riders and their myths.
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Old 04-01-2012, 03:18 AM   #35
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Originally Posted by perterra View Post
How long does it take to go from tooling along the highway lightly holding the grips with your toes on the pegs to standing back on the pegs and moving back on to the rear of the seat?

In the cases where I have had to react to an emergency it would all be over by the time you did your shifting around.
Yep, typically during a true emergency stop you are puckered so strongly to the seat that moving back is not possible.
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Old 04-01-2012, 03:08 PM   #36
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Clarification

Let's clarify a few things:
  1. I'm not advocating standing up to execute an emergency stop on pavement. My question is whether or not it makes sense to shift your weight back in the process of performing the manuever. If so, then my top box is in the way of optimally effective braking.
  2. It takes roughly 3.4 seconds to perform a 0.8g stop from 60 m.p.h. (probably the upper limit of the KLR's braking ability). There is time to shift your weight. Admittedly, this would require practice.
Some may think my idea stupid. In all honesty, I appreciate the feedback. We don't learn anything from people we agree with. My goal is to continue, and never stop, increasing my riding knowledge and skills. So debate or flame away in whatever manner suits you.

Just don't call me late for dinner.
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Old 04-01-2012, 03:36 PM   #37
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Quote:
Originally Posted by Capt_Aubrey View Post
Let's clarify a few things:
  1. I'm not advocating standing up to execute an emergency stop on pavement. My question is whether or not it makes sense to shift your weight back in the process of performing the manuever. If so, then my top box is in the way of optimally effective braking.
  2. It takes roughly 3.4 seconds to perform a 0.8g stop from 60 m.p.h. (probably the upper limit of the KLR's braking ability). There is time to shift your weight. Admittedly, this would require practice.
Some may think my idea stupid. In all honesty, I appreciate the feedback. We don't learn anything from people we agree with. My goal is to continue, and never stop, increasing my riding knowledge and skills. So debate or flame away in whatever manner suits you.

Just don't call me late for dinner.

There is time during the stop maybe, but I'm not sure there is 3 seconds where you have time to do the above. In my few times of braking avoidance, it has been probably closer to a second and a half till I was on the ground trying to get my breath back. Now this wasnt 60 mph but closer to 35 or 40 in dirt, and for the most part on pavement I have found the Shinko golden boy 244 tires to not really give a shit what kind of gyrations you do they still handle pavement like your on ball bearings.

I have a pretty big top box and am 5' 11" and there is no way for me to get back over my seat wings and get tangled up with it.




I think it would work okay on a dirt bike or dual sport with a seat like a banana but if you put a road sofa on it it's pretty hard to get back that far.

I'm not about to tell you how you should ride, you do it ever how you want. But for me it's a non issue, in a trip of 500 miles I'll use the rear brake maybe 2 times.
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Old 04-01-2012, 05:29 PM   #38
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While I understand how the braking technique in the OP would be useful in the dirt, riding on paved roads is different.

First, PROGRESSIVE application of the brake, whether front or rear. Never stab or grab it. If you can't do this in a panic stop, you need to practice progressive application of the brake as an emergency technique.

Second. An unweighted wheel will lock up and slide sooner than a properly loaded wheel. So with progressive application of the front brake, the weight will shift towards the front as the wheel loads. The increased load will increase tire grip on the pavement, and require yet more brake pressure to lock up. using progressive application will give you feedback that will allow you to sense what the proper maximum brake pressure is given the current road conditions.

Third, as the weight transfers toward the front, the rear wheel unloads, requiring less brake pressure to lock it up and cause a slide.

Your premise that moving your weight back will increase the loading of the rear wheel and increase it's stopping capability is actually a valid premise. However, the front brake provides the majority of stopping power, and by shifting your weight towards the rear wheel, you are decreasing it's ability to provide hard braking without locking up due to the decreasing weight on it from your body weight shift. The net result is that, on pavement, you decrease the stopping power of your bike and increase the stopping distance by shifting your weight to the rear.

I've not ridden a KLR. But I've never ridden a motorcycle where the rear brake stopped a bike faster than the front when either is used exclusively.

In an actual panic stop on the streets of LA on a sport bike at 35 mph, I executed a full stop in an amazingly short distance using only the front brake with progressive application of pressure. I did end up doing a bit of a stoppie, but I stopped the bike before hitting the vehicle that cut me off, and did not lose control of the bike. The conditions were dry pavement, and the controls used took advantage of that.
I'd rather be in full control of the bike, even if in a stoppie than have either wheel lock up and slide. A sliding bike is a lot harder to control on pavement than one where the loaded wheel(s) has(have) grip.
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Old 04-01-2012, 08:44 PM   #39
RayAlazzurra
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The perfect tire and other braking myths

I agree with Capt. A. The top box is not a big issue imo, but it could be a factor in stopping distance.

Imagine a bike equipped with only a front brake--no rear brake. This mythical motorcycle also has a perfect front tire that will not slide no matter what stopping force is required. What determines the stopping distance when traction is limitless?

Only the geometry of the bike/rider combination and the slope of the road.

The lower and further to the rear the center of gravity is the greater the stopping force that can be applied before the rear tire begins to lift. Once the rear tire begins to lift the center of gravity lifts with it so it is all over at that point. For best braking motorcycles should be built long and low with a center of gravity to the rear. Some cruiser bikes like Honda's Valkrie stop really well--better than some sportbikes. The reason is that a sportbike often has a stubby wheelbase, higher c of g, and more forward weight bias and all of these are bad for stopping. Motorcycle design is a compromise. We want a high wheelbase and low c of g for braking and acceleration, but we want a short wheelbase and a higher c of g for cornering and stability.

I wear shirts with a 37 inch sleeve and do try to push myself backward when stopping hard. I've never tried scooting my butt back, but it could theoretically help. I've never seen a good road racer fail to sit up when braking. Staying in a tuck would make the back end even more squirrely under heavy braking.

Those who are flaming Capt. A have a point in the sense that none of this is MSF approved dogma. If I were an MSF instructor I would have a hard enough time just getting students to use the front brake effectively. Try to teach people to move their butts around and it complicates the issue. In every real emergency stop I have ever made I have locked the rear at least briefly. (and I know better--my bike has 130,000 miles on the original rear brakes) The back brake is so easy to lock under maximum braking that those who argue for front brake only emergency stops also make a good point.

The physics of braking agree with Capt. A's assertion.
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Old 04-01-2012, 09:19 PM   #40
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Quote:
Originally Posted by Capt_Aubrey View Post

I was trained to make emergency stops by using modest amounts of rear brake (just enough to keep the bike tracking in a straight line), getting my butt up out of the saddle and back as far as possible, and smoothly/quickly applying as much front brake as possible. Moving my body of the saddle and rearward moves the center of gravity of the bike/rider back, unweighting the front wheel, which means you can apply more front brake with reduced risk of a stoppie or endo.

Thoughts?
I think whoever it was that "trained" you was confusing Off-road loose descents with On-road Threshold braking.

The Blue highlighted above is counter productive to stopping quickly.
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Old 04-02-2012, 01:12 AM   #41
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Quote:
Originally Posted by Capt_Aubrey View Post
Let's clarify a few things:
  1. I'm not advocating standing up to execute an emergency stop on pavement. My question is whether or not it makes sense to shift your weight back in the process of performing the manuever. If so, then my top box is in the way of optimally effective braking.
  2. It takes roughly 3.4 seconds to perform a 0.8g stop from 60 m.p.h. (probably the upper limit of the KLR's braking ability). There is time to shift your weight. Admittedly, this would require practice.
Some may think my idea stupid. In all honesty, I appreciate the feedback. We don't learn anything from people we agree with. My goal is to continue, and never stop, increasing my riding knowledge and skills. So debate or flame away in whatever manner suits you.

Just don't call me late for dinner.
If the technique works on seal, every roadracer would be using it.

They have a squillion times stronger brakes than adventure bike riders on the street.

They don't.

QED.
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Old 04-02-2012, 05:58 AM   #42
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Your braking technique sounds like something a person riding a road bicycle would do. It's only necessary on a road bicycle because they will endo so easily because of the extremely steep rake on the fork, and they usually have no front shock to aid weight transfer to the front tire before it just locks. Thus it is necessary to get some weight back. Also useful for steep descents over loose surfaces on a mountain bike.

On motorcycles, on pavement, scooting backwards is completely pointless. Stay seated, squeeze the brake, let the weight go forward onto the front tire so you can squeeze even more front brake. It's actually a lot harder to endo a motorcycle than most people think -- you have to be actively trying pretty hard to do it. The KLR has pretty long travel in the front fork so you're probably freaking out because you feel the front end diving so much under braking.
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Old 04-02-2012, 07:26 AM   #43
RayAlazzurra
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Doctor's Dangle?

Quote:
Originally Posted by PJay View Post
If the technique works on seal, every roadracer would be using it.

They have a squillion times stronger brakes than adventure bike riders on the street.

They don't.

QED.
Actually they do move their weight. Ever watch a guy named Rossi? He was sort of famous for a while before he made that fateful decision to join Ducati... Watch him sit up, push as far back as possible, and even hang his leg out and back, all in an effort to keep his rear tire on pavement. The limit for road race bikes is geometry because the tires are so sticky and the brakes so powerful that traction becomes a much smaller consideration.

A KLR is a whole 'nother matter. I think this debate is a lot like the debate over hanging off while cornering on a road bike. Hanging off helps, but it is no substitute for using the right turn point and countersteering effectively. Body positioning is probably the last skill to learn after mastery of the other skills has been obtained. Body positioning can help while braking, particullarly on a downhill stop on pavement from high speed.
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Old 04-02-2012, 06:08 PM   #44
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Quote:
Originally Posted by Capt_Aubrey View Post
Let's clarify a few things:
  1. I'm not advocating standing up to execute an emergency stop on pavement. My question is whether or not it makes sense to shift your weight back in the process of performing the manuever. If so, then my top box is in the way of optimally effective braking.
  2. It takes roughly 3.4 seconds to perform a 0.8g stop from 60 m.p.h. (probably the upper limit of the KLR's braking ability). There is time to shift your weight. Admittedly, this would require practice.
Some may think my idea stupid. In all honesty, I appreciate the feedback. We don't learn anything from people we agree with. My goal is to continue, and never stop, increasing my riding knowledge and skills. So debate or flame away in whatever manner suits you.

Just don't call me late for dinner.

Capt.

The best way to find out is to practice(someplace safe). Use both techniques and keep the one that fits you the best. You are the only one responsible for what happens on your bike.
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Old 04-02-2012, 06:24 PM   #45
bloodandmotoroil
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i say his way is 100% correct... it is the quickest way to stop.


whouldn't you agree?

hitting the object infront of you ( the REASON you are hitting the breaks) would stop you MUCH quicker than
any of the other methods.
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