Emergency Braking [Archive] - Kiwi Biker forums

p.dath

9th August 2009, 14:37

OutForADuck made this comment:

THIS IS ALL MY OWN OPINION AND PLEASE ACCEPT OR REJECT IT AS PART OF YOUR OWN SKILL SET, BUT I FELT STRONGLY ENOUGH ABOUT SOME OF THIS "NEW" RIDER ADVICE TO COMMENT

On any road you will stop much quicker using both brakes.

Throttle position under emergency braking , don't worry about it too much. Except for ensuring it is closed, or you will drastically reduce your braking power

Downshifts under normal braking - blipping can smooth things out but modulating the clutch by letting it out slowly and feeling what the bike is doing is a far more important skill. The clutch is not good gradual control and expensive when you wear it out. You should try to learn how to ride smoothly shifting with the clutch (or without when you get better) as if the clutch was a switch. Blipping the throttle will allow you to do this effectively.. Takes practice but becomes completely automatic after a while

Covering the front brake all the time is generally a Good thing, But don't stress about it and its only really important in traffic situations so don't bother when your on the track or out on that country road.

1/2/3 finger braking is generally a bad thing, especially for inexperienced riders. On a modern well maintained bike using all four fingers on the front brake is a recipe for disaster. All modern bikes will allow you to lock the front wheel with only two fingers, even at speed and under panic with four fingers you are going to be in trouble. Combine this with the way our hands work and you'll realise that the first and second fingers are controlled by muscles that have evolved for fine control whereas the third and fourth fingers use much larger and more isometric muscles. If you don't believe me try writing using a pen held only with your thumb and little finger and then try with your first finger and thumb

Most experts say to apply the rear brake momentarily before the front. If braking is done the other way, it causes the back of a bike to sag and reduces weight over the front tyre. However it's irrelevant as for most riders (inexperienced or otherwise), when they grab the brakes their hand reaches the front lever quicker than the foot presses the back. If you can form a habit of always applying the rear brake first then the back you will be in a good position. The reason for this is many fold, Firstly its an additional braking forec and even on sports bikes will help. Secondly it works as a stabiliser, helping to keep the bike pointing straight while you brake, thirdly it compresses the suspension (especially the back, but also the front) which lowers the bike and allows you to brake harder before the rear looses traction, also because it compresses the front as well it helps enormously with the progressive loading of the front tyre helping to reduce your chances of locking it, Lastly (maybe) it does all this even if you lock it up (very common with new and old riders alike) so you get the benefits even if you are still trying to get the skills

Use the rear brake only for slow speed maneuvers (around walking speed). A bike is much easier to manouvere without the front end bouncing up and down. REally good advice, execpt the ONLY part

On extremely slippery surfaces such as mud, wet grass or ice, use only the rear brake. The reason for this is that it if the front wheel "washes out" under braking, it almost always results in the bike falling. I'll agree with all except that you can and should learn how to lock the front and recover. The feelings you get from locking the front wheel are very similar to letting go of the front brake and if you don't train to leanr them you will pull harder and longer and then you will fall over. But if you can "feel" the front locking (or tucking as we often say) then letting go of the brake momentarily will result in it hooking up again (unless you found that diesel patch we all hate, but then you were doomed anyway

Learn to sit up during hard braking. and take all the weight through your hips and off your arms, locked elbows and weighted arms will result in locked control of the bike

Always be on the lookout for an escape route.

Emergency StoppingAs soon as you stop after an emergency, look behind. There's a high chance you'll have stalled the bike and/or not be in 1st gear. If a car/truck etc is immenently heading towards you at speed then get off the bike and run.

Everyone is different and has a preference to how they brake but the most important thing is practice, practice, practice.

p.dath

9th August 2009, 14:43

My thoughts are that we should re-write the section on emergency braking, and base it on factual data rather than personal experience. This is because everyone has different views on the subject, and it is hard to debate those personal views. On the other hand, facts are more clear cut.

I would like to put forward this article as an initial discussion point:
http://www.fmq.qc.ca/pdf/amorce-freinage_eng.pdf
This article was written by the "Promocycle Foundation" (who works as consultants in the field of motorcycle safety) where they conducted 298 emergency stops, and determined the most important factors when performing an emergency stop.
I think this would form a good factual basis for the wiki article.

YellowDog

9th August 2009, 15:33

Revised Emergency Braking Section:

1. Buy a bike with ABS.
2. Squeeze the front and stamp on the back brake as hard as you like.
3. Enjoy living longer.

But yes I do agree with a lot of what you have said; especially with the front braking, which can be extremely dangerous, particularly at low speeds.

scracha

9th August 2009, 18:12

I think this would form a good factual basis for the wiki article.

Was basing it partly on experience, partly on motorcycle magazines but mostly on DSA advice given to me when I was an instructor (for a very short time) in the UK. Find a study that covers the issue using more than a handful of riders and in adverse weather and surface conditions. For every study that says one thing, there's a dozen others that have a different conclusion.

Aside from the issue of "front first vs back first" which I mention in the Wiki as being contentious (most studies say front then back, but I personally think it's dependent on bike type and center of gravity) I don't think I contradict the study you reference in any way? I'm of the front first opinion. I could argue
Why would I want to compress the rear?
Why would I really give a stuff about reducing the chance of the rear reducing traction?
How does the rear brake compress the front?
How does it place more braking force over the front wheel...you know...the wheel that in dry conditions is providing around 95% of the braking force".
I could go on but the front vs back first argument has been going on for years. The fact that it's still often debated should probably be mentioned in the wiki.

"Rear brake only", yeah, bit ambiguous so it should be reworded "Use just the rear brake during slow speed maneuvers"

Totally disagree about covering the front brake all the time for new riders. First thing they do is panic and grab a handfull.

Also disagree about 2 or 3 finger braking. For new riders, we're not talking about 6 piston radial calipers...we're talking ginny 250's and hyobags. 2 finger braking on one of these babies is likely to result in trapped fingers and hitting things a lot harder.

Throttle position in emergency stop has very little overall effect on braking distance and for a newish rider, it's far more important that they're concentrating on squeezing the brakes as quickly as possible and looking where they are going than worrying about if they've closed the throttle or what gear they're in.

I think you're missing the point anyhoo. The main points I emphasised for a new rider is to avoid hazards and practise practise practice,

1. Buy a bike with ABS.
2. Squeeze the front and stamp on the back brake as hard as you like.
3. Enjoy living longer.

Ha..I actually liked that. Yeah, there should be a bit about ABS in there. The Wiki thingie is just a starter and should be added to as peeps see fit.

Perhaps a bit about using the rear brake on some bikes to settle it into a turn. Also about using the back brake a little if running a bit hot in a corner. Maybe about using the front brake to slow down a LOT more than the rear. Still need to get the focus on anticipating hazards (thus avoiding emergency stops) and looking for escape routes.

There should be loads of other articles for new riders such as
"get professional instruction, don't just ask your mates or take your dad's word as gospel"
"don't ride along hugging the left hand kerb"
"you will more than likely crash so get some good gear"

Oh discussion thing. The Wiki thingie has a discussion part and I personally think we should be discussing it there.

p.dath

9th August 2009, 18:40

...Oh discussion thing. The Wiki thingie has a discussion part and I personally think we should be discussing it there.

But it doesn't work very well. It doesn't indicate you said what, and it is not threaded. There's no indication when new comments have been added. This forum works tonnes better at discussions.

p.dath

9th August 2009, 18:43

scracha, you seem quite knowledgable. Would you like to update the wiki article and incorporate some of the ideas above?

I think it would be good to also site some reference study (like they do on the real wikipedia) to support your view point. Otherwise I think we run the risk of people changing the article back and forward according to their view, rather than it being an authoritative article of fact.

Perhaps over time several references might be quoted showing the range of commonly held opinion.

Hitcher

9th August 2009, 19:00

1. Buy a bike with ABS.

All bikes come fitted with ABS as standard equipment.

OutForADuck

10th August 2009, 11:59

YellowDog

10th August 2009, 12:41

All bikes come fitted with ABS as standard equipment.
Since getting and ABS bike I do use the back brake a great deal more than before. This is because I know it won't lock at a crucial moment.

Most people I know, other than when moving slowly, don't use the back brake at all.

IME - You are able to maintain greater control over the bike when using both front and back brakes appropriately rather than just the front (like most I know do). Changing down gear early is also a big help.

Benk

10th August 2009, 16:20

Downshifts under normal braking - blipping can smooth things out but modulating the clutch by letting it out slowly and feeling what the bike is doing is a far more important skill. The clutch is not good gradual control and expensive when you wear it out. You should try to learn how to ride smoothly shifting with the clutch (or without when you get better) as if the clutch was a switch. Blipping the throttle will allow you to do this effectively.. Takes practice but becomes completely automatic after a while

Hi guys, just having a nosey here, but I thought the clutch was used to smooth the power from the gearbox to the ground?

The clutch ISNT an on off switch, and isnt supposed to be. Thats why its a clutch. Replacing a clutch is cheap, replacing a gearbox is expensive.

Benk

10th August 2009, 16:35

"you will more than likely crash so get some good gear"

Good advice bro. What do you use? :laugh:

The Stranger

10th August 2009, 16:47

I would like to put forward this article as an initial discussion point:
http://www.fmq.qc.ca/pdf/amorce-freinage_eng.pdf

Ah, yeah, how many of us have outriggers, or for that matter a significant weight aft of the rear axle (of course the rear just gained additional stopping power)?
I would have to read it again to get actual figures, but from memory about 2/3 of the attempts were excluded as they were non compliant. If experienced riders can't get it right 2/3 of the time is it really an appropriate method. You can't rewind and take another shot, it may well be curtains.

Plus this topic has been done to death.

sil3nt

10th August 2009, 17:45

Is this statement wrong?

Most experts say to apply the rear brake momentarily before the front. If braking is done the other way, it causes the back of a bike to sag and reduces weight over the front tyre. However it's irrelevant as for most riders (inexperienced or otherwise), when they grab the brakes their hand reaches the front lever quicker than the foot presses the back.
Shouldn't it say apply the front first?

NDORFN

10th August 2009, 17:58

YellowDog

10th August 2009, 18:09

I don't use the rear brake at all, ever. Maybe if I was riding something with a particuarly heavy rear wheel I'd give it a very light tap to kill the momentum, but I'd never use the rear as a form of deceleration. I prefer to devote any momentary thought that's left after spending the majoriy of my attention on front braking and riding position to collision avoidance. That little split second it would take to tell my right foot to help out is a split second that can be spent telling my balls to pitch in and get some more lean on or get ready to make a safe bail.
You are quite typical and I am sure that you are very skilled with it too. However for slower speeds the front brake does not give you the required control.

I suspect you won't agree as you are probably an expert with quick dabs to give you great control.

IME:

Back Brake = set up and control with moderate stopping power.
Front brake = immediate and rapid stopping power.

Hopefully a compromise where both of these can be used for optimal riding safety and control, as per the writeup.

If you do what you do really well, don't change anything.

NDORFN

10th August 2009, 18:42

You are quite typical and I am sure that you are very skilled with it too. However for slower speeds the front brake does not give you the required control.

I suspect you won't agree as you are probably an expert with quick dabs to give you great control.

IME:

Back Brake = set up and control with moderate stopping power.
Front brake = immediate and rapid stopping power.

Hopefully a compromise where both of these can be used for optimal riding safety and control, as per the writeup.

If you do what you do really well, don't change anything.

I totally agree on your experience with back brake setup, which is one important thing I forgot to include in my post... although I would describe my setup more as "light" than "moderate". My rear brake pedal is set up so that it's soft and spongey and would take a good plant from the foot to get anything out of it. I originally set it up that way because I found myself accidently pressing it when I was riding, but now I keep my foot under the lever anyway.

p.dath

10th August 2009, 18:45

Is this statement wrong?

Shouldn't it say apply the front first?

Negative. Read the study at the beginning of the thread. The Motorcycle road code says to apply the rear brake as well.

boomer

10th August 2009, 18:50

who wrote that shit.. if i had time i'd comment.

NDORFN

10th August 2009, 20:02

Negative. Read the study at the beginning of the thread. The Motorcycle road code says to apply the rear brake as well.

The Motorcycle Road Code also says to stand up on the pegs when encountering loose gravel. If the Motorcycle Road Code was commercialised, it would probably be sponsored by Hyosung. COME ON!

Benk

10th August 2009, 20:13

The Motorcycle Road Code also says to stand up on the pegs when encountering loose gravel.

Thats actually fucking good advice mate.

Done any MX riding? Others read this stuff, so it pays to know something before posting. :jerry:

NDORFN

10th August 2009, 20:21

Thats actually fucking good advice mate.

Done any MX riding? Others read this stuff, so it pays to know something before posting. :jerry:

When you stand up on your Moto X bike is it's center of gravity around your ankles? No? It's way up around your thighs isn't it... in which case it makes sense to stand up. Reckon a dude on a Harley is going to fare better on gravel by standing on his pegs? On most road bikes, riding on gravel standing on pegs not only puts you in a position that you're not used to riding in (unlike a Moto X bike where you spend most of your time standing anyway), it also leaves you unable to throw a foot down to catch a slide. If you want to compare to other forms of riding, look at speedway. Ever seen someone loop the track standing on his pegs? The Motorcycle ROAD Code is for the ROAD, and for many different types of bikes, so it shouldn't be so specific on either of the issues (rear brake use OR standing up). Worst thing is, you can actually fail the test if you don't agree! I wouldn't call it fucking good advice mate, I'd call it fucking buraucratic bullshit. You probably won't find much of that in your Motorcycle OFFroad Code.

The Stranger

10th August 2009, 20:23

I originally set it up that way because I found myself accidently pressing it when I was riding, but now I keep my foot under the lever anyway.

You do?
Do you go around corners?

sil3nt

10th August 2009, 20:47

Negative. Read the study at the beginning of the thread. The Motorcycle road code says to apply the rear brake as well.Sorry but reading that sentence i quoted is saying using the front brake causes the rear to sag and weight to move away from the front. That seems to be opposite of what really happens.

In fact the whole paragraph is rather poorly written and confusing. I am not trying to be rude i am an inexperienced rider who would like to read and learn on good practices.

I went back earlier in the thread and found the rest of the paragraph

Most experts say to apply the rear brake momentarily before the front. If braking is done the other way, it causes the back of a bike to sag and reduces weight over the front tyre. However it's irrelevant as for most riders (inexperienced or otherwise), when they grab the brakes their hand reaches the front lever quicker than the foot presses the back. If you can form a habit of always applying the rear brake first then the back you will be in a good position. The reason for this is many fold, Firstly its an additional braking forec and even on sports bikes will help. Secondly it works as a stabiliser, helping to keep the bike pointing straight while you brake, thirdly it compresses the suspension (especially the back, but also the front) which lowers the bike and allows you to brake harder before the rear looses traction, also because it compresses the front as well it helps enormously with the progressive loading of the front tyre helping to reduce your chances of locking it, Lastly (maybe) it does all this even if you lock it up (very common with new and old riders alike) so you get the benefits even if you are still trying to get the skillsIn bold is another confusing area.

NDORFN

10th August 2009, 21:12

You do?
Do you go around corners?

Nope. Just go straight off the road and die. And on the odd occassion that I do go around, especially when it's a right hander, I keep my foot under the brake pedal so it'll get minced. Doesn't everyone do this?

p.dath

10th August 2009, 21:22

I have substantialy re-written the section on braking now.

http://www.kiwibiker.co.nz/wiki/Braking

I've broken it into sections, as I came to the conclusion that the reason there is a lot of different answers about braking is because there are a lot of different situations we get into that require an emergency stop.

While I based the article on a comprehensive test report, I think it could now benefit from input from advanced riders (certainly more advanced than me!), and it should also be easier to add sections to cover emergency braking in different scenarios.

_STAIN_

10th August 2009, 21:27

Is this statement wrong?

Shouldn't it say apply the front first?

statement is true

NDORFN

10th August 2009, 21:37

NDORFN

10th August 2009, 21:38

Try saying "Various theories varies" five times fast.

_STAIN_

10th August 2009, 21:41

rear brake is used more for handling control than braking. ie. can help you pull a tighter line in or smoothe the power delivery on exit

NDORFN

10th August 2009, 21:44

rear brake is used more for handling control than braking. ie. can help you pull a tighter line in or smoothe the power delivery on exit

Can you give a little more detail on how that works? Does it pull a tighter line by sliding the rear out? How does it smoothen power delivery on exit?

p.dath

10th August 2009, 22:04

It's true assuming your bike isn't an '87 GPX250. Don't worry Sil3ntwar, I've been through it all on my '88. Just practice at a safe speed until you've found the technique and setup that offers the best results. The effects of various theories varies so much from bike to bike (particularly due to age and condition of suspension) that you'll have to practice and learn new habbits when you upgrade anyway.

Actually that was one interesting conclusion the report came to - that the technique for stopping in the shortest distance was not affected by the type of bike. They found you used the same technique no matter what.

p.dath

10th August 2009, 22:11

I don't use the rear brake at all, ever. Maybe if I was riding something with a particuarly heavy rear wheel I'd give it a very light tap to kill the momentum, but I'd never use the rear as a form of deceleration. I prefer to devote any momentary thought that's left after spending the majoriy of my attention on front braking and riding position to collision avoidance. That little split second it would take to tell my right foot to help out is a split second that can be spent telling my balls to pitch in and get some more lean on or get ready to make a safe bail.

The report found that using the rear brake as well as the front increased the average de-acceleration from -0.711 g to -0.774 g. So using both brakes makes a difference. They also noticed it only makes a difference at the very beginning of the process.

p.dath

10th August 2009, 22:13

IME - You are able to maintain greater control over the bike when using both front and back brakes appropriately rather than just the front (like most I know do). Changing down gear early is also a big help.

Interesting enough they spent an entire day investigating the effect of down shifting during emergency braking. The report found that down shifting as part of emergency braking INCREASED the distance to stop by around 2m.

So you can down shift as you approach something, but forget doing it once the emergency starts happening. Your time is better spent doing other things.

_STAIN_

10th August 2009, 22:17

Can you give a little more detail on how that works? Does it pull a tighter line by sliding the rear out? How does it smoothen power delivery on exit?

some thing you just need to try when riding. in a slowish moderately tight corner, you find it tightening up, just apply a little rear brake. the bike will pull a tighter line.
maybe hard to feel the effect on a gpx, but on more powerful bikes we feather the rear brake to control power delivery while leaned over. Once upright release and your gone, technique commonly used in racing. Cheers

NDORFN

10th August 2009, 22:25

Actually that was one interesting conclusion the report came to - that the technique for stopping in the shortest distance was not affected by the type of bike. They found you used the same technique no matter what.

Does the phrase "Type of bike" refer only to makes and models, or does it encompass ages and conditions aswell. If you got on an old GPX250 like Sil3ntwars' and put some rear brake on then applied the fronts, everything would get very perpendicular all of a sudden. Don't ask me how the physics work, but I know from experience that they lurch forward no matter which brake you use, taking all the weight off the rear and putting too much on the front. Getting the front brake on first get's the weight foward and the rider prone for adding in some gentle rear brake. It's probably only a factor in bikes with slushy suspension.

NDORFN

10th August 2009, 22:29

some thing you just need to try when riding. in a slowish moderately tight corner, you find it tightening up, just apply a little rear brake. the bike will pull a tighter line.
maybe hard to feel the effect on a gpx, but on more powerful bikes we feather the rear brake to control power delivery while leaned over. Once upright release and your gone, technique commonly used in racing. Cheers

I don't actually ride the GPX anymore. I'm in the process of aquiring a ZXR so it's something I'll test out. I can sort of imagine how it'd work. Cheers for the advice.

p.dath

10th August 2009, 22:37

Does the phrase "Type of bike" refer only to makes and models, or does it encompass ages and conditions aswell. If you got on an old GPX250 like Sil3ntwars' and put some rear brake on then applied the fronts, everything would get very perpendicular all of a sudden. Don't ask me how the physics work, but I know from experience that they lurch forward no matter which brake you use, taking all the weight off the rear and putting too much on the front. Getting the front brake on first get's the weight foward and the rider prone for adding in some gentle rear brake. It's probably only a factor in bikes with slushy suspension.

They mostly compared sport bikes and cruisers.

I don't have sufficient experience to really answer the question, but they found that the rear brake only had any impact at the very beginning of the exercise. I would think if your getting a "perpendicular" effect you still need the rear brake, but less of it. :)

The Stranger

10th August 2009, 23:07

mossy1200

10th August 2009, 23:18

The whole point of rear brake first is that it lowers the bike and the weight transfer enlargens the contact patch of the front tyre.
Personally I use the back brake just before applying the front in wet conditions on the track as a planned approach braking prior to corners as I feel it reduces the chance of losing traction when the front is applied hard.
I release the rear brake after the front has taken effect.
I think that you will find some bikes like cbr1100x and many beemer use linked brakes to lower the bike under brakes and they do stop quite quickly with that method.

NDORFN

11th August 2009, 08:12

Benk

11th August 2009, 08:17

I wouldn't call it fucking good advice mate, I'd call it fucking buraucratic bullshit. You probably won't find much of that in your Motorcycle OFFroad Code.

Haha, have you tried it? I suggest you do, as you can go much faster, and more stable on gravel. Might save you (or more likely someone else reading this) from falling off one day.

Anyway, Im done. Ive got nothing to prove to some know all on the interweb.

sinfull

11th August 2009, 08:30

I'd hate to see a learner, come across an emergency braking scenario and have a flashback from this thread ! The word sideways springs to mind !

But then i guess most learners would go for the rear brake first anyway aye ?

Rear brakes are for wet whites lines or grass in my book ! I generally ride with two fingers hovering over the brake lever, by the time my toes have lifted off the peg and move to the brake pedal, i would have scrubbed 50% off my speed !

If ya want to get into trail braking to have the rear squating in a corner and to help save the wheel from spinning up on the corner exit (talking track here) Well shit i cant help ya, as i aint even that experienced on the track yet (experimented with it, but i got enough to try and think about before that becomes habit)

NDORFN

11th August 2009, 08:32

Haha, have you tried it? I suggest you do, as you can go much faster, and more stable on gravel. Might save you (or more likely someone else reading this) from falling off one day.

Anyway, Im done. Ive got nothing to prove to some know all on the interweb.

Of course I haven't tried it. That would involve actually riding a bike and well, that would mean I'd have to leave my computer. No, I just sit here making shit up all day. Look at my profile, I don't even have a bike! Seriously though, why would you want to encourage people to go faster on gravel with thier road bikes? Especially the begginers who are most likely to read this shit.

p.dath

11th August 2009, 09:40

The "comprehensive" test is significantly flawed as noted.

Learn to think for yourself.

I guess I disagree with you. But the thing with Wiki's is to quote sources of information that support your point of view, so that a nice factual line is formed.

I think if would be great it you could add a piece to the wiki and also cite a significant study to support your view, so that it becomes a richer document.
Otherwise it is just here-say.

Benk

11th August 2009, 09:46

Seriously though, why would you want to encourage people to go faster on gravel with thier road bikes? Especially the begginers who are most likely to read this shit.

People are going to go fast without encouragement, at least feeling the front wheel break loose at 60kms on gravel might help you overcome the 'do too much instinct' and crash when the same thing happens at 120.

Having that knowledge about what a bike can and cant do, helps every aspect of riding. Knowing you can do 90kms on rough gravel means that you know you can confidently and safely ride at 70km an hour, and be confident with what you are doing.

The Stranger

11th August 2009, 10:10

I guess I disagree with you. But the thing with Wiki's is to quote sources of information that support your point of view, so that a nice factual line is formed.

I think if would be great it you could add a piece to the wiki and also cite a significant study to support your view, so that it becomes a richer document.
Otherwise it is just here-say.

You disagree that our bikes don't have outriggers?
Or that a significant weight rear of the rear axle assists the rear brake?
Or that they were unable to get experienced riders to get it right more than a third of the time?

Personally I think it would be great if people who didn't even know what they don't know didn't post their opinions as fact, but clearly that isn't about to happen either. At best it will mean an argument with someone some time because they read it on the internet, at worst it will mean someone relies on incomplete or incompetent advice and dies.

For example you haven't covered many of the basics of braking even.

How do you apply pressure? grab hard and fast? Why not, it's an emergency isn't it?
What effect does weight transfer have and why is this significant?
Chain chatter - often the first time people hear it they panic and release the brake - is this a good idea? you don't think it would be worth a mention?
If you apply the rear first, then weight transfers to the front, what is likely to happen to the rear? (hint, it's likely to lock) what will this do? - a) reduce braking traction and b) eliminate a gyroscope (those things which keep a motorbike perpendicular to the ground).
You don't mention differences between sport bikes and cruisers re which brakes are more effective and the effects of the COG and rake on front brakes.
What about the most basic, yet frequently overlooked maintenance items, ok, it's not the maintenance section, but maintenance is a part of safe and efficient braking so is worth a mention.

So yes, others can come along and correct you, but that's no excuse for lazy sloppy work on your part.

The Stranger

11th August 2009, 10:19

People are going to go fast without encouragement, at least feeling the front wheel break loose at 60kms on gravel might help you overcome the 'do too much instinct' and crash when the same thing happens at 120.

Having that knowledge about what a bike can and cant do, helps every aspect of riding. Knowing you can do 90kms on rough gravel means that you know you can confidently and safely ride at 70km an hour, and be confident with what you are doing.

You are of course quite right, but you're wasting your time.
He can drive a keyboard so he's an expert.

OutForADuck

11th August 2009, 10:28

You are of course quite right, but you're wasting your time.
He can drive a keyboard so he's an expert.

I've been staying out of this quite a bit because to be frank there are always going to be more opinions than facts and no matter what we feel we know none of us can be right in the miriad of situations out there.

But the discussion should continue. I have noticed as a result that the wiki has already improved alot and, although can never and should never be seen as the absolute authority, is far more informative than previously. Great stuff for those riders looking for answers.

I like the general overriding concept throughout everyones comments... Practice Practice Practice.

Now my opinion.... lines up with The Stranger (strangely enough :angry2:)
Remember you can't practice emergency stopping by coming to a gentle stop at a red light. If you want to be practiced at the extreme.. practice at the extreme.. just approach it carefully and in a controlled manner.

The Stranger

11th August 2009, 10:39

I like the general overriding concept throughout everyones comments... Practice Practice Practice.

Yes, practice is mentioned in the wiki, however in reality this is THE most important point and will make a bigger difference to stopping distance than any amount of discussion on technique.

sinfull

11th August 2009, 10:45

Yes, practice is mentioned in the wiki, however in reality this is THE most important point and will make a bigger difference to stopping distance than any amount of discussion on technique.
Aint no better place to do this than at the track !
You will soon learn where you and your bikes capabilities lie !

Just a quick plug for my sponsors !!!! :yes:

Damn, what sponsors !

SpankMe

11th August 2009, 13:01

Moved out of the wiki as it's for NZ specific topics, not general motorcycling.

Leyton

11th August 2009, 13:48

I know its been flamed to death.. and everyone has different riding styles.. this is what I have observed..

Using both brakes at the same time is very important, The back brake works best as a trailer helping to keep the bike settled under extreme braking, your rear wheel has next to no traction anyways braking that hard! All weight transfer is being obsorbed where your tyre meets the road(Traction), and in the tyre, and forks itself.
Standing on your footpegs you do infact shift the center of gravity to your pegs, The bike is riding you! Give it what it wants, feed it wisely. Weight on pegs is noticeable more on gravel, and shifting weight from one side to the other at slow speeds under gyro effect.. has alot to do with how that back wheel wants to track. You also can, and recommended.. once again.. depends on your style and bike.. shift the wait to the lowest point of gravity and mass by choosing the opposing peg, helping stabilize the rear end, it also could save your ass if the back slides out at risk of high side, providing that you do not crap yourself and chop/close the throttle.

I have never used the rear coming out of a corner for stability. I tend to just use the classic crack'n'rollon method.. OH and HANG ON!

Leyton

11th August 2009, 13:52

Aint no better place to do this than at the track !
You will soon learn where you and your bikes capabilities lie !

Just a quick plug for my sponsors !!!! :yes:
Damn, what sponsors !

Too true, I might look into a track day to cement a few learnings that I have had over the months.

LOL

NDORFN

11th August 2009, 14:22

All this talk about riding makes me want to get a bike!

Leyton

11th August 2009, 14:35

All this talk about riding makes me want to get a bike!

:( I understand!!!!

dipshit

11th August 2009, 14:41

Why would I want to compress the rear?

To reduce the tendency for the bike to pitch forward and top out the rear end and make it feel light.

Why would I really give a stuff about reducing the chance of the rear reducing traction?

Because of the reduced stability.

How does the rear brake compress the front?

It squats/pulls down the rear end and keeps the bike flatter.

Try this for yourself to demonstrate. Do a hard complete stop using both brakes up to a set of traffic lights, say. Keep holding both brakes on after you have come to a complete stop for a couple of seconds... now release the rear brake pedal only. You will probably feel the back end of the bike rise up.

How does it place more braking force over the front wheel...you know...the wheel that in dry conditions is providing around 95% of the braking force".

It gives the bike more stability and a pushing down into the road feeling rather than a rising and floating feeling. This encourages you to go harder on the front brake.

All the new ABS systems coming out are also linked systems for this reason. It is to increase stability by reducing a bike's tendency to pitch forward and lift the rear end if using front brake only.

Leyton

11th August 2009, 14:44

You will probably feel the back end of the bike rise up.

Good test.

NDORFN

11th August 2009, 14:48

:( I understand!!!!

...which is why I'm going to pick up a new one on Thursday :wari:

Leyton

11th August 2009, 14:55

...which is why I'm going to pick up a new one on Thursday :wari:

YEEEEEHAAA!!!!! PM Me what you got and we should organize a mini ride some place :) I am booked up this next few weekends for riding :/ But I am sure I should be able to get in about a couple of hours in mid avo for a short ride:scooter:

sinfull

11th August 2009, 18:57

To reduce the tendency for the bike to pitch forward and top out the rear end and make it feel light.

Because of the reduced stability.

It squats/pulls down the rear end and keeps the bike flatter.

Try this for yourself to demonstrate. Do a hard complete stop using both brakes up to a set of traffic lights, say. Keep holding both brakes on after you have come to a complete stop for a couple of seconds... now release the rear brake pedal only. You will probably feel the back end of the bike rise up.

It gives the bike more stability and a pushing down into the road feeling rather than a rising and floating feeling. This encourages you to go harder on the front brake.

All the new ABS systems coming out are also linked systems for this reason. It is to increase stability by reducing a bike's tendency to pitch forward and lift the rear end if using front brake only.Have you actually seen this guy ride lol talk about defy gravity !

I hope that one day if the need arises, i can have the calmness you portrayed in the above post, to gently touch the back brake, so to enduce the correct pitch, while i avoid the gentleman or lady who has just PULLED THE FUCK IN FRONT OF ME !

Have you ever seen the dude you quoted in your post defy gravity ? If not, you should lol, elbows and thighs

Touch the rear to stop the bike pitching forward when you apply the front brake my arse !!! Yes my arse pitches forward !!!!!!!!!!!!!!!!!!

A/ If you are worried your arse may lose traction, soften the rear rebound so the rear travells north faster (if it slaps your arse, harden it up a tad) (but did you realllllllly try to emergency brake )
B/ stay off the rear brake, It's only good for white lines or grass !

scracha

11th August 2009, 19:10

who wrote that shit.. if i had time i'd comment.

Me ya coont...before other folks edited it

Negative. Read the study at the beginning of the thread. The Motorcycle road code says to apply the rear brake as well.

So what...other more important..sorry...countries with larger populations say use the front brake first.

>hy would I want to compress the rear?
To reduce the tendency for the bike to pitch forward and top out the rear end and make it feel light.

But wouldn't I want to keep the centre of gravity high and have the bike to pitch forward to increase the force over the front wheel?

>Why would I really give a stuff about reducing the chance of the rear
>reducing traction?
Because of the reduced stability.

But if I don't use much rear brake won't the rear wheel keep spinning and have a nice gyroscopic effect to stop it going sideways. I'm not Jay Lawrence and always find my bike going sideways if I so much as touch the rear brake when racing.

>How does the rear brake compress the front?
It squats/pulls down the rear end and keeps the bike flatter.

So I'll ask again, how does the rear brake compress the front?

Try this for yourself to demonstrate. Do a hard complete stop using both brakes up to a set of traffic lights, say. Keep holding both brakes on after you have come to a complete stop for a couple of seconds... now release the rear brake pedal only. You will probably feel the back end of the bike rise up.

Soo...umm...how does this compress the front?

>How does it place more braking force over the front wheel...you know...the
>wheel that in dry conditions is providing around 95% of the braking force".
It gives the bike more stability and a pushing down into the road feeling rather than a rising and floating feeling. This encourages you to go harder on the front brake.

But I want the "pushing down in the road feeling" on the front tyre, since that's why there's nice long forks to absorb all these forces and lots of pistons and twin discs to slow it down ?

All the new ABS systems coming out are also linked systems for this reason. It is to increase stability by reducing a bike's tendency to pitch forward and lift the rear end if using front brake only.

Disagree. They're linked because bikes stop quicker using both brakes. Not just for lazy riders like me that only use the front in the dry (I struggle to reach the rear on sportsbikes and I'm more worried about it locking up then the minimal additional braking force it gives me) but research on our poorly trained motorcycling cousins shows that a hell of a lot of them go splat because they're only using the REAR brake. ABS is more stable because when a wheel locks up it releases. Show me an ABS system on a sportsbike that applies the rear first and I'll perhaps give the "back brake first" theory some weight.

mossy1200

11th August 2009, 19:30

You forget that bikes with linked brakes send more power to front than rear due to calipers and disc size.
Rear brakes have small disc and single pot calipers and use of the rear is an assist to stoping unless you want to almost stand on the rear lever.
Rear brake lowers the bike and loads force onto the front without increased tendancy to fully compress the front shocks as quicky therefore the rear wheel is less likely to lift off the ground than if you suddenly jam on the front.If you think this is wrong apply some rear at 100ks and then say your bike doesnt lower front and rear.
Cruisers will often get better results than a light sports bike as they have longer wheel base and softer shocks.But if you also look at the nature of a sports bikes rear brake system as being light on stoping power you will relise thats it was never intended to do much more than help out with the task of stoping.
I guess you could lobby with manufactures to have rear brakes removed from production if you think they are a waste of time.Then we could save a few hundred on each bike we buy.

sinfull

11th August 2009, 19:55

Disagree. They're linked because bikes stop quicker using both brakes. Not just for lazy riders like me that only use the front in the dry (I struggle to reach the rear on sportsbikes and I'm more worried about it locking up then the minimal additional braking force it gives me) but research on our poorly trained motorcycling cousins shows that a hell of a lot of them go splat because they're only using the REAR brake. ABS is more stable because when a wheel locks up it releases. Show me an ABS system on a sportsbike that applies the rear first and I'll perhaps give the "back brake first" theory some weight.Agree to disagree !! Under hard braking my arse tends to waggle round horrendously as it is ! Perhaps it has to do with the fact i have mediocure standard supension, but i wouldn't like to add a touch of the back brake to it !

Rear brake lowers the bike and loads force onto the front without increased tendancy to fully compress the front shocks as quicky therefore the rear wheel is less likely to lift off the ground than if you suddenly jam on the front..
It is something you have said twice now and sinking in springs to mind !
I'm tending to want to give it some thought whilst coming down the pit straight at manfeild !!!
But not however when some Coooont pulls out in front of me !
Which Mossy, (my learnered and possibly faster on the track friend) is what the thread was about ! Emergency braking for learners !~

I say again learners should take it to the track and try these ideas !
I quite possibly may have learnt something new today and will be testing this theory at the track ! Writes it down, writes it down before i have to go back to this post to remember tonight bwahahahahahaha !

mossy1200

11th August 2009, 20:16

Agree to disagree !! Under hard braking my arse tends to waggle round horrendously as it is ! Perhaps it has to do with the fact i have mediocure standard supension, but i wouldn't like to add a touch of the back brake to it !

It is something you have said twice now and sinking in springs to mind !
I'm tending to want to give it some thought whilst coming down the pit straight at manfeild !!!
But not however when some Coooont pulls out in front of me !
Which Mossy, (my learnered and possibly faster on the track friend) is what the thread was about ! Emergency braking for learners !~

I say again learners should take it to the track and try these ideas !
I quite possibly may have learnt something new today and will be testing this theory at the track ! Writes it down, writes it down before i have to go back to this post to remember tonight bwahahahahahaha !
The thing is if you use the both then in emergency you also use both.
The real effects are in the wet.Moderation on the rear is the key.
Also I used to own cbr1100x and was always front brake only guy prior.
Then when upgraded bike started notice difference from using one to both.More at higher speeds.
Now I ride bonneville on the road and the front brake(one only) is not brilliant
so I use both and even use the back to control rate of decent.If you ever ride a new t100 you will understand how poor the front brake is by itself.

sinfull

11th August 2009, 20:23

The thing is if you use the both then in emergency you also use both.
The real effects are in the wet.Moderation on the rear is the key.
Also I used to own cbr1100x and was always front brake only guy prior.
Then when upgraded bike started notice difference from using one to both.More at higher speeds.
Now I ride bonneville on the road and the front brake(one only) is not brilliant
so I use both and even use the back to control rate of decent.If you ever ride a new t100 you will understand how poor the front brake is by itself.
Just bought an interstate today lol (goes back to the post where it says find an escape route)

mossy1200

11th August 2009, 20:29

I guess the idea is to find what works best for you and your bike then use that method all the time so that its second nature in an emergency.Its easy to cruise and go with the flow but you need to ride like everyone is likely to take you out at any moment.Cause than can and often do.
Lazy riding doesnt promote a great responce if you need to stop quick.

dipshit

11th August 2009, 20:38

(but did you realllllllly try to emergency brake )

Was attending a rider training day recently when the instructor was getting us to do front brake only emergency stops from 100kph. My shortest stopping distance was my first run when i used both front and rear in my normal fashion. It was a good stop - as short as anybody else managed to do that day.

Several front only runs overshot my first mark. I just wasn't getting the feedback and stability and stuck to the road feeling i could get with both.

sinfull

11th August 2009, 20:55

Was attending a rider training day recently when the instructor was getting us to do front brake only emergency stops from 100kph. My shortest stopping distance was my first run when i used both front and rear in my normal fashion. It was a good stop - as short as anybody else managed to do that day.

Several front only runs overshot my first mark. I just wasn't getting the feedback and stability and stuck to the road feeling i could get with both.
And after reading Mossy's post again and letting it sink in, i could see where the point your making IE: Having the bike settle on the suspension, could help in stopping distance but again, practice ? I got the track ! Perhaps the WIKI should just have the address of this rider training day, rather than any number of learners point of view ?
I can appreciate the debate thats gone on here today and have perhaps learnt from it (won't know till i test this)
But can still see problems if a learner rider reads the thread and then comes across an emergency situation, where he thinks back brake first ! Helllo, sideways !!!!
My suspension is set hard in compression clicks (not altered it since track) but yet to be tested in an emergency on the road ! For some unknown reason i'm not so interested in road riding anymore !

dipshit

11th August 2009, 21:04

But wouldn't I want to keep the centre of gravity high and have the bike to pitch forward to increase the force over the front wheel?

No. Not for stability and quick stopping anyhow. The trend to pitch the front down is for steepening the rake for helping to turn into corners. It isn't necessarily the best thing for stopping quickly.

But if I don't use much rear brake won't the rear wheel keep spinning and have a nice gyroscopic effect to stop it going sideways. I'm not Jay Lawrence and always find my bike going sideways if I so much as touch the rear brake when racing.

That's why i think sometimes you race guys don't actually know everything like you think you do.

So I'll ask again, how does the rear brake compress the front?

Compresses the whole bike down.

But I want the "pushing down in the road feeling" on the front tyre, since that's why there's nice long forks to absorb all these forces and lots of pistons and twin discs to slow it down ?

In this vid at 2:20 a Honda tech starts talking about the stability and preventing dive from using both brakes together on their linked ABS system.

http://www.youtube.com/watch?v=BqwIm8pH8z0

Disagree. They're linked because bikes stop quicker using both brakes.

And isn't that the whole point of it?

Show me an ABS system on a sportsbike that applies the rear first and I'll perhaps give the "back brake first" theory some weight.

I don't think I apply the rear brake first. I would say virtually at the same time. Just touching the rear brake... not trying to stop the bike with it... at the same time as easing on the front brake and then going harder and harder on it.

Take a look at the attachment below. A big heavy BMW with linked ABS and a Duolever front end that doesn't dive much under brakes anyhow absolutely cleaned up a 675 in a braking test. I really don't think a high centre of gravity and lots of pitch forwards is the best for stopping quickly.

p.dath

11th August 2009, 21:15

And after reading Mossy's post again and letting it sink in, i could see where the point your making IE: Having the bike settle on the suspension, could help in stopping distance but again, practice ? I got the track ! Perhaps the WIKI should just have the address of this rider training day, rather than any number of learners point of view ?
I can appreciate the debate thats gone on here today and have perhaps learnt from it (won't know till i test this)
But can still see problems if a learner rider reads the thread and then comes across an emergency situation, where he thinks back brake first ! Helllo, sideways !!!!
My suspension is set hard in compression clicks (not altered it since track) but yet to be tested in an emergency on the road ! For some unknown reason i'm not so interested in road riding anymore !

Did you read the research article that was sited? The testing they did was pretty comprehensive, and they did more emergency brake tests than most of us will ever do in our life times. It guess its hard letting facts speak for themselves.

sinfull

11th August 2009, 21:28

Did you read the research article that was sited? The testing they did was pretty comprehensive, and they did more emergency brake tests than most of us will ever do in our life times. It guess its hard letting facts speak for themselves.
And i say again, Practice ! Or should i tell my daughter that it's ok to do as P.dath says cause it's what is written down !!!! No i did not read it ! Why would i read a research artical about a test rider (with obviously a high skill level) testing theories ? I'll leave that up to you theorists !
No i'm sorry my friend ! I hit the front first because i have slid sideways into a car, i have also slid sideways into a ditch ! both on cruisers, both due to using the back brake ! Have you ?
No ! Perhaps not !

p.dath

11th August 2009, 21:35

And i say again, Practice ! Or should i tell my daughter that it's ok to do as P.dath says cause it's what is written down !!!! No i did not read it ! Why would i read a research artical about a test rider (with obviously a high skill level) testing theories ? I'll leave that up to you theorists !
No i'm sorry my friend ! I hit the front first because i have slid sideways into a car, i have also slid sideways into a ditch ! both on cruisers, both due to using the back brake ! Have you ?
No ! Perhaps not !

Actually it was a whole bunch of test riders on a couple of different bikes, and they analysed the factors from all of them to determine the best method of stopping in the shortest time.

The best way of saving your daughters life would be to get her to practice the approach they found best.

Then again, you could try doing 800 odd emergency braking tests like they did across a couple of different bikes with many different riders and come to a better conclusion.
As I said, they probably did more emergency braking stops than most of us are likely to do in our whole lifetimes.

scracha

11th August 2009, 21:49

As I said, they probably did more emergency braking stops than most of us are likely to do in our whole lifetimes.
Used to demonstrate about 4 every Saturday morning and a few more if I was working Sundays and evenings. Commuting in and out of Edinburgh also resulted in far too frequent emergency stops.

That's why i think sometimes you race guys don't actually know everything like you think you do

First time I've been called a "race guy". I've only been racing 3 seasons. Until I started racing I pretty much rode on the road every day (14 years)

I never once recommended using only front brake BTW (on the track I avoid it cos it normally results in my ending on the grass but i've never told anyone to only use the front on the road)

In the original wiki thingie I gave my arguments for front momentarily before back. I acknowledged that some studies say back before front. I explained that some bikes react differently to others. I used the phrase "practise, practise, practise". If you guys want to change the wiki then go ahead. I felt my original post was pretty balanced.:innocent:

sinfull

11th August 2009, 21:51

Then again, you could try doing 800 odd emergency braking tests like they did across a couple of different bikes with many different riders and come to a better conclusion.
As I said, they probably did more emergency braking stops than most of us are likely to do in our whole lifetimes.
Perhaps i might just do that many in the next 6 months or so ! While you sit and read your theories p.dath !
You will i hope note, that my interest in the wiki has deminished in the last day or so !
I first thought Cool, somewhere for newcomers to motorcycling to pick up tips !
But it turns out it's somewhere for theorists to post their theories !! (Oh with many back up articals they may have read, i might add)
Something i might add to the Wiki !!!
Don't sit and read too much, as it will only distract you from the fact, that you will only learn where your or your bikes capabilities lie, by riding your bike !

You i believe (i could be wrong, but not too often) are all talk, with very little practical experience behind you !

scracha

11th August 2009, 21:53

Actually it was a whole bunch of test riders on a couple of different bikes, and they analysed the factors from all of them to determine the best method of stopping in the shortest time.

Don't they teach ya at school here to gather your information from more than once source.

p.dath

11th August 2009, 22:04

Perhaps i might just do that many in the next 6 months or so ! While you sit and read your theories p.dath !
You will i hope note, that my interest in the wiki has deminished in the last day or so !
I first thought Cool, somewhere for newcomers to motorcycling to pick up tips !
But it turns out it's somewhere for theorists to post their theories !! (Oh with many back up articals they may have read, i might add)
Something i might add to the Wiki !!!
Don't sit and read too much, as it will only distract you from the fact, that you will only learn where your or your bikes capabilities lie, by riding your bike !

You i believe (i could be wrong, but not too often) are all talk, with very little practical experience behind you !

I do not consider myself experienced in this area, so you are correct.

I also know that simply practising on your own has limited use. I've tried that. You need to practice with someone better than you, or learn (aka read) from a better source than yourself. This is because you don't know what you don't know. If someone has gone to the trouble of doing a large number of stops, and found a very good method than I am certainly going to give it my attention - and practice that method.

On the other hand, it seems you haven't even given these people the decency to read the results of the considerable amount of work they have put in. Perhaps you'll read it and learn nothing because you already know more than them. Then again maybe you'll learn sometime in the ten minutes of time you'll need to invest that may save your life.

p.dath

11th August 2009, 22:06

Don't they teach ya at school here to gather your information from more than once source.

I haven't found much compelling information to the contrary that was backed up by more than heresay.

The NZ motorcycle road code also backs up the report.

Googling on the subject suggests a lot of information either way.

sinfull

11th August 2009, 22:09

On the other hand, it seems you haven't even given these people the decency to read the results of the considerable amount of work they have put in. Perhaps you'll read it and learn nothing because you already know more than them. Then again maybe you'll learn sometime in the ten minutes of time you'll need to invest that may save your life. You sir are probably well read ! I on the other hand am on the tail end of a very hard day on the bourbon hahahaha you go read a book and i'll have another bourbon ! Agree to disagree ! You stop quickly and i'll go round the outside ok ?

p.dath

11th August 2009, 22:11

You sir are probably well read ! I on the other hand am on the tail end of a very hard day on the bourbon hahahaha you go read a book and i'll have another bourbon ! Agree to disagree ! You stop quickly and i'll go round the outside ok ?

I think I shall join you, but I am more desperate for a beer. :)

mossy1200

11th August 2009, 22:23

It seems we have concluded that brakes should only be used as we approach pubs or if there is insufficient room to pass cars.
Vodka gets you where you wanna go quicker guys.

Ixion

11th August 2009, 22:25

Well, that was an informative thread, wasn't it.

dipshit

11th August 2009, 22:26

Anybody remember the Graham Crosby "when you got to stop, use the lot" tv ads?

scracha

12th August 2009, 11:38

I haven't found much compelling information to the contrary that was backed up by more than heresay.

The NZ motorcycle road code also backs up the report.

Googling on the subject suggests a lot of information either way.

You didn't look very hard.

Here is what's written in "The Official DSA Guide to Riding: The Essential Skills" book: Written and compiled by UK Driving Standards Agency.

Many motorcycle riders are, quite wrongly, afraid to use the front brake. This is often as a result of what they were taught as cyclists.

On a motorcycle....

• you must normally use both brakes
• the front brake is more powerful of the two brakes and the most important when stopping a motorcycle.

TO STOP MOST EFFECTIVELY

In good road conditions...

• apply the front brake just before you apply the rear brake
• apply greater pressure to the front brake

Applying greater pressure to the front brake gives the best stopping power in good conditions because...

• the combined weight of the machine and rider is thrown forward
• the front tyre is pressed more firmly on the road , giving a better grip

In wet or slippery conditions you need to apply a more equal pressure to both front and rear brakes.

USING ONE BRAKE ONLY

You'll take much longer to stop by using one brake only. But at very low speeds (walking pace) using only the rear brake gives smoother control.

WHEN TO BRAKE

Always look and plan well ahead to avoid having to brake sharply. A gradual increase of pressure on the brakes is better than late, harsh braking.

Follow these rules...

• brake when your machine is upright and moving in a straight line
• brake in good time
• adjust the pressure on the brakes according to the road surface and weather conditions.

WHERE TO BRAKE

Where you brake is very important. The best time to brake is when you're travelling upright in a straight line.

Braking on a bend - A good rider will plan well ahead to avoid braking on a bend.

On a bend the combined weight of motorcycle and rider is thrown outwards, To balance the rider leans inwards.

If you brake on a bend...

• the weight will be thrown outwards even more
• the motorcycle and rider may become unstable
• the tyres may lose their grip on the road surface

If you must brake on a bend...

• avoid using the front brake. Rely on the rear brake and engine braking to slow you down. If you must use the front brake, be very gentle. There's a risk of the front tyre losing its grip and sliding sideways
• try to bring your motorcycle upright and brake normally, provided you can do so safely.

Now bearing in mind the population, the amount of research they've done into the subject and the fact th at the NZ road code is a joke (70kmph learners limit and being able to drive for 30 minutes with light off after sunset to name just two stupid elements) then I know which agency guidelines I'd believe.

Devil

12th August 2009, 12:05

Well, that was an informative thread, wasn't it.

I find it quite concerning the misinformation in this thread, also the explanations on why things occur, or why we do what we do.

Is there a Nobel prize for attempted physics? Yikes.

I think the world would be better off if this thread was deleted.

Edit: For what it's worth. The linked, servo assisted ABS system on my GS Adventure is the absolute shiznit.

NDORFN

12th August 2009, 12:25

Devil

12th August 2009, 12:39

dipshit

12th August 2009, 12:51

* The front brake is the most effective
* Use both brakes progressively

No shit. Yet we have a lot of track day junkies and instructors running around telling everybody to use the front only. :doh:

p.dath

12th August 2009, 12:56

I do concurr with your DSA article scracha, with perhaps the order of the braking. In the study that was done they found the read brake only had any impact for a very short period of time, before the weight was transferred onto the front wheel.

p.dath

12th August 2009, 13:01

The moral of the story here is that if you have to read up on how to stop your bike most effectively in an emergency then you shouldn't even be on the road. Every bike is obviously different and in different condition, and the first thing you should do when you ride a new one is find the most effective braking technique for that bike. I'm glad this shit isn't going into Wiki.

That's not a helpful view to take NDORFN. How do you propose people initially learn? Just by jumping on a bike and giving it a go?

It's no different to learning something in school. If you wanted to become a bike mechanic you can't just sit in front a bike and start playing (unless you want to be a very poor mechanic). You need to learn from others with more experience, read service manuals, study the different aspects of the machines you are working on.
Sure practice and trial and error are part of the equation - but if that is all you do you wont end up progressing very far.

The problem is, you don't know what you don't know. And if you don't take the time to learn you'll end up learning bad habits that may cost you your life.

I hope I don't stop learning. And I expect I'll still be seeking the advice of experts and reading well conducted research in decades to come.

p.dath

12th August 2009, 13:03

No shit. Yet we have a lot of track day junkies and instructors running around telling everybody to use the front only. :doh:

I've been told exactly that as well! Bit like on here - pointless arguing with them about it.

Each person has their own opinion. Those most wrong die, so I guess it is self correcting.

dipshit

12th August 2009, 13:17

I've been told exactly that as well! Bit like on here - pointless arguing with them about it.

Yeah, they have a photo of themselves on a race track. They obviously have much superior skills and knowledge. :sleep:

The Stranger

12th August 2009, 13:23

Yeah, they have a photo of themselves on a race track. They obviously have much superior skills and knowledge. :sleep:

And for the sake of clarification, your personal experience with emergency braking amounts to?

dipshit

12th August 2009, 13:34

And for the sake of clarification, your personal experience with emergency braking amounts to?

Being able to stop my bike quicker than the way a track day instructor was advising with his front only baloney.

Disco Dan

12th August 2009, 13:40

Err thought this was a discussion on the best braking practice?

All I found was one or two posts by some very experienced riders - the rest of the thread is basically noobs who think they know everything...

dipshit

12th August 2009, 13:43

Sorry for not having a photo of myself on a race track.

The Stranger

12th August 2009, 13:43

Being able to stop my bike quicker than the way a track day instructor was advising with his front only baloney.

Sorry, I missed that, wasn't aware we had a trackday instructor here.
So you tested this?

dipshit

12th August 2009, 13:46

Sorry, I missed that, wasn't aware we had a trackday instructor here.
So you tested this?

Yes... http://www.kiwibiker.co.nz/forums/showpost.php?p=1129349696&postcount=68

The Stranger

12th August 2009, 14:02

Yes... http://www.kiwibiker.co.nz/forums/showpost.php?p=1129349696&postcount=68

Ah, that post didn't really make it clear that it was a trackday or the the instructor was advocating front only - we regularly get people to use back only for example to clearly demonstrate how much worse it is than the front.

Who was the instructor by the way?

dipshit

12th August 2009, 14:23

Who was the instructor by the way?

Brian Bernard.

The Stranger

12th August 2009, 14:29

Brian Bernard.

Fark who the hell does he think he is?
Like he'd know anything about riding a motorcycle.

dipshit

12th August 2009, 14:42

Fark who the hell does he think he is?
Like he'd know anything about riding a motorcycle.

And here lies the problem.

boomer

12th August 2009, 15:02

And here lies the problem.

oh dude.. you really don't have any idea how much of an ass you've made of yourself in this thread.

:clap:

dipshit

12th August 2009, 15:03

Yes, how (dare) I question his holiness the instructor.

boomer

12th August 2009, 15:04

Yes, how dear I question his holiness the instructor.

do you know his pedigree?

google it/him !

And it's dare not dear ;)

Chrislost

12th August 2009, 15:05

p.dath

12th August 2009, 15:14

what...
like the fact that everyone rides differently?
as it stands now i believe further gains could be achieved by downshifting and using engine breaking rather then the foot brake, and possably teaching people how to back it into that driveway that the car just half-pulled out of...

They tested changing down, and found that you stopped faster if you didn't - because it took too long to do and that time was better used in the rest of the braking procedure. You have a limited amount of time, and using the rear brake instead produced a better result.

dipshit

12th August 2009, 15:15

do you know his pedigree?

Yes i know who he is. So what..???

boomer

12th August 2009, 15:16

And here lies the problem.

Yes i know who he is. So what..???

It must be quite difficult in your world.. do conversations never seem to end?

dipshit

12th August 2009, 15:19

It must be quite difficult in your world.. do conversations never seem to end?

You people are making my point for me without me having to say much.

The Stranger

12th August 2009, 15:20

It must be quite difficult in your world.. do conversations never seem to end?

Well, it's a "fact" that skidmark can stop from 60kph in 2m.
I think we can comfortably put dipshit in the same group as skidmark.

p.dath

12th August 2009, 15:22

what...
like the fact that everyone rides differently?
as it([edit] wiki) stands now i believe further gains could be achieved by downshifting and using engine breaking rather then the foot brake, and possably teaching people how to back it into that driveway that the car just half-pulled out of...

They also tested a group of riders, and found the procedure for stopping in the shortest distance was the same amongst those riders. So that issue that people ride differently doesn't seem to affect it much.

Disco Dan

12th August 2009, 15:25

You people are making my point for me without me having to say much.

Well done dipshit :niceone:

The Stranger

12th August 2009, 15:27

They also tested a group of riders, and found the procedure for stopping in the shortest distance was the same amongst those riders. So that issue that people ride differently doesn't seem to affect it much.

Why do you persist in quoting a flawed study and steadfastly refusing remove you head from the sand to even acknowledge the flaws?

Chrislost

12th August 2009, 15:31

They tested changing down, and found that you stopped faster if you didn't - because it took too long to do and that time was better used in the rest of the braking procedure. You have a limited amount of time, and using the rear brake instead produced a better result.

what if one was to be like, changing down as they used the front and rear brakes?
would they not stop within .5 of a m of the other guy AND be in a position to save their bike should a truck be doing 100km.h behind them?

[edit] Can you please explain to me what the "rest of the procedure" is?

dipshit

12th August 2009, 15:35

I think we can comfortably put dipshit in the same group as skidmark.

So because a guy that's good at going around and around in circles fast, say something... then without question you take it as gospel..???

I see how this works now. Someone with lots of photos of themselves on a race track is more superior to someone with only a couple of photos of themselves on a race track... who is more superior to people with no photos of themselves on a race track.

At least that's how the world must work for you guys. :rofl:

boomer

12th August 2009, 15:38

So because a guy that's good at going around and around in circles fast, say something... then without question you take it as gospel..???

I see how this works now. Someone with lots of photos of themselves on a race track is more superior to someone with only a couple of photos of themselves on a race track... who is more superior to people with no photos of themselves on a race track.

At least that's how the world must work for you guys. :rofl:

your logic is flawed..are you female?

i do, however, believe an instructor who uses his practical skills daily in addition to his theory may know a thing or two.

you even put forward arguments like a woman ! :fag:

Disco Dan

12th August 2009, 15:40

The world according to a dipshit:

So because a guy that's good at going around and around in circles fast, say something... then without question you take it as gospel..???

I see how this works now. Someone with lots of photos of themselves on a race track is more superior to someone with only a couple of photos of themselves on a race track... who is more superior to people with no photos of themselves on a race track.

The world according to everyone else:

I see how this works now. Someone who talks a load of crap is less superior to someone who does not talk a load of crap.

R6_kid

12th August 2009, 15:43

So because a guy that's good at going around and around in circles fast, say something... then without question you take it as gospel..???

I see how this works now. Someone with lots of photos of themselves on a race track is more superior to someone with only a couple of photos of themselves on a race track... who is more superior to people with no photos of themselves on a race track.

At least that's how the world must work for you guys. :rofl:

When emergency braking (as in very hard) from any decent speed, on a modern(ish) (sports)bike it is likely that the rear wheel will not be in touch with the ground.

I've got lots of pics of me on the track so you'd better listen to what I have to say.

p.dath

12th August 2009, 15:46

Why do you persist in quoting a flawed study and steadfastly refusing remove you head from the sand to even acknowledge the flaws?

I do agree with you that using outriggers, and putting a additional weight on the back of the bike might have an impact. I guess the question is the size of the impact.

The outriggers were used to protect the riders. Otherwise you can be certain some of them would have came off while trying to work out the best way to stop in the shortest distance.

The box was needing to caring the instrumentation they used.

It would have been useful if they tried deliberating adding more weight to the back of the bike to see how much of an effect it had. Then we would have an impression of the effect their box was having.

Do consider though that they did use a group of riders, and those riders would all have had different weights, and that the difference in weights between those riders did not impact the results. They also used bikes of different weights, and that did not affect the outcome either.

So I don't agree that it invalidates the study, or that it is flawed as a result - but do acknowledge that my measuring the experiment they would have affected it.

dipshit

12th August 2009, 15:47

boomer

12th August 2009, 15:49

This is how trends and fades take hold. People followed blindly what other people do without thinking about it for themselves.

Front brake only just happens to be the trend and the thing to do amongst the track guys at the moment.

Will you shut the fook up about the track...! maybe a name change will have a paradigm affect on your thought process..

p.dath

12th August 2009, 15:51

what if one was to be like, changing down as they used the front and rear brakes?
would they not stop within .5 of a m of the other guy AND be in a position to save their bike should a truck be doing 100km.h behind them?

[edit] Can you please explain to me what the "rest of the procedure" is?

As I said, they did some 800 emergency brake tests with a variety of riders - initially letting the riders do what they thought would produce the best results. Then they narrowed the test down to around 298 of the more successful tests, and isolated out the factors that made a different.

You'll see in the report that those riders that changed down increased their stopping distance by around 1.5m on average. So your better to not practice this method.

The report is here:
http://www.fmq.qc.ca/pdf/amorce-freinage_eng.pdf

p.dath

12th August 2009, 15:54

When emergency braking (as in very hard) from any decent speed, on a modern(ish) (sports)bike it is likely that the rear wheel will not be in touch with the ground...

They did find that the rear brake only had any impact right at the very beginning of the braking manoeuvre, and after that had almost no effect. As soon as the weight transfers off it to the front tyre it was not effective.

Chrislost

12th August 2009, 15:56

As I said, they did some 800 emergency brake tests with a variety of riders - initially letting the riders do what they thought would produce the best results. Then they narrowed the test down to around 298 of the more successful tests, and isolated out the factors that made a different.

You'll see in the report that those riders that changed down increased their stopping distance by around 1.5m on average. So your better to not practice this method.

The report is here:
http://www.fmq.qc.ca/pdf/amorce-freinage_eng.pdf

lets have a stop off!
name a road and a starting speed above 200.
i will downshift, you can do whatever your report says.

dipshit

12th August 2009, 16:02

i do, however, believe an instructor who uses his practical skills daily in addition to his theory may know a thing or two.

Yet i could stop my bike in a shorter distance using both brakes than i could when i was just using the front only.

The Stranger

12th August 2009, 16:03

So because a guy that's good at going around and around in circles fast, say something... then without question you take it as gospel..???

I see how this works now. Someone with lots of photos of themselves on a race track is more superior to someone with only a couple of photos of themselves on a race track... who is more superior to people with no photos of themselves on a race track.

At least that's how the world must work for you guys. :rofl:

Damn, you couldn't have picked a more appropriate user name could you?

On the one hand we have a guy that's good at going around and around in circles very fast and has lots of photos of himself on a race track, says something AND it is born out by observation of about 2,000 emergency braking runs over the last 5yrs.
On the other we have dipshit and his drop kick d.path and their only real world experience is a flaky study and a "I went to the track once".
Decisions, decisions.

dipshit

12th August 2009, 16:09

On the other we have dipshit and his drop kick d.path and their only real world experience is a flaky study and a "I went to the track once".

Well it's also funny how most bikes with linked braking systems stop quicker with more control than bikes with riders on them who are probably doing the trendy front only stops.

SixPackBack

12th August 2009, 16:13

Damn, you couldn't have picked a more appropriate user name could you?

On the one hand we have a guy that's good at going around and around in circles very fast and has lots of photos of himself on a race track, says something AND it is born out by observation of about 2,000 emergency braking runs over the last 5yrs.
On the other we have dipshit and his drop kick d.path and their only real world experience is a flaky study and a "I went to the track once".
Decisions, decisions.

Hell I'm sold, those girls really seem to know what they is talkin' about.

The Stranger

12th August 2009, 16:13

So I don't agree that it invalidates the study, or that it is flawed as a result - but do acknowledge that my measuring the experiment they would have affected it.

So, what would be the likely effect of adding more weight rear of the rear axle then?

p.dath

12th August 2009, 16:14

lets have a stop off!
name a road and a starting speed above 200.
i will downshift, you can do whatever your report says.

The average emergency stopping time was a just over three seconds. How many times do you think you can downshift during that time in an emergency?

So lets say you are applying your front brake hard. The weight is on the front wheel. At this point in time the rear brake has little impact (almost unmeasurable). You change down. With the weight on the front wheel do you still feel that engine braking will have an impact - even though the rear brake does not? And if so, why do you feel engine braking will help when the rear brake will not?

They did find that engaging the clutch did help, so that could be your saving grace. :)

Chrislost

12th August 2009, 16:17

Yet i could stop my bike in a shorter distance using both brakes than i could when i was just using the front only.

Pretty sure that they tell you this so that you dot get confused reaching for all the different leavers and knobs while that fkn car is pulling out in front of you.

EFFECTS OF DECELERATION FORCE
The mean deceleration for the group of 298 passes braking from 100 km/h to zero wa -0.898 g in a mean time
of 3.18 seconds. During these more than 3 seconds, the rider had to manage his braking while subjected to a considerable
deceleration force against his arms and hands which must in large measure support his upper body. A
simulator designed to recreate this force would have to incline the motorcycle on its front wheel at an angle of
64 degrees.

they obvoiusly used knob ends like boomer for their tests as most riders know to hold the tank with their knees

The Stranger

12th August 2009, 16:27

Well it's also funny how most bikes with linked braking systems stop quicker with more control than bikes with riders on them who are probably doing the trendy front only stops.

Also interesting that most journos slammed the linked brakes on the Blackbird (exact same system on the VFR's) and many sites show you how to unlink the brakes.

The linked systems on modern BMWs are exceptional, though the only ones I have seen have been antilock also (which means the rear can't lock as weight is transferred) so I would be happy to see a comparrison between modern linked BMWs without ABS if you have one thanks.

The Stranger

12th August 2009, 16:28

So lets say you are applying your front brake hard. The weight is on the front wheel. At this point in time the rear brake has little impact (almost unmeasurable).

Unless of course you have a full size Mac computer in a protective case rear of the rear wheel.

Chrislost

12th August 2009, 16:40

the average emergency stopping time was a just over three seconds. How many times do you think you can downshift during that time in an emergency?

So lets say you are applying your front brake hard. The weight is on the front wheel. At this point in time the rear brake has little impact (almost unmeasurable). You change down. With the weight on the front wheel do you still feel that engine braking will have an impact - even though the rear brake does not? And if so, why do you feel engine braking will help when the rear brake will not?

They did find that engaging the clutch did help, so that could be your saving grace. :)

If i had to emergency stop i would assume that the back wheel would be airbourne.
i would still use the rear brake.
i would still be in first by the time i had stopped.
[edit] i would still stop faster then you

p.dath

12th August 2009, 16:44

Unless of course you have a full size Mac computer in a protective case rear of the rear wheel.

:) Haha. Yes if you could increase the friction of the rear wheel with more weight that would help.
However without such benefit I ask again, what additional affect will engine braking have over the rear brake once the front brake is applied hard.

I think almost none. So not worth spending time changing down.

mossy1200

12th August 2009, 16:48

Also interesting that most journos slammed the linked brakes on the Blackbird (exact same system on the VFR's) and many sites show you how to unlink the brakes.

The linked systems on modern BMWs are exceptional, though the only ones I have seen have been antilock also (which means the rear can't lock as weight is transferred) so I would be happy to see a comparrison between modern linked BMWs without ABS if you have one thanks.
I had a blackbird and the linked brakes were awesome.People like to post methods of removal of system because the think they have the ability to be better than the system that was carefully designed for them(may be true for the top 5% of riders).Then they think they can make a hyper sports tourer bike into sports bike.These same people that post this information most likely stick the cheepest organic no name pads that they can source from ebay also to save money.

As far as race riders giving advice on braking goes.They treat every approach to every corner as if it was a life or death manoeuvre cause if they dont they get passed under brakes.

I will agree that back brakes do very little once the front end is compressed as rear becomes light but the initial effect of them scrubing off speed at the beginning of the braking makes a huge impact on the total stopping distance.
After all its the stopping distance that saves your life if you get in trouble.
5metres can be the difference between contact with another vehicle or leaving the road.

The most important thing that people are not mentioning in this thread is to use the best method every time you stop so that its second nature when you need it.There is a difference between knowing how and doing in a panic situation and I would back second nature before decision makers every time.

*****If you ride like you mean business then you will do the business when it counts.******

Adding more weight means increased stopping distance.Only so much grip on a tyre and additional weight just makes things worse.Thats the law of physics(larger the mass the more force required to stop).Try better suspension equals better stopping distance.Thats a formular that will work.Or even correct tyre pressures.

Ixion

12th August 2009, 16:50

I..
The most important thing that people are not mentioning in this thread is to use the best method every time you stop so that its second nature when you need it.There is a difference between knowing how and doing in a panic situation and I would back second nature before decision makers every time.

..

And that just saved the thread from total pointlessness.

R6_kid

12th August 2009, 16:54

If i had to emergency stop i would assume that the back wheel would be airbourne.
i would still use the rear brake.
i would still be in first by the time i had stopped.
[edit] i would still stop faster then you

The point about not changing down is valid. It's emergency braking, not slowing down for a corner. The few times I've had to emergency brake I've never bothered changing down, apart from the time when I had no front brakes in which case it certainly felt like changing down was slowing the bike faster than the rear brake was.

jamestwin

12th August 2009, 16:57

If i had to emergency stop i would assume that the back wheel would be airbourne.
i would still use the rear brake.
i would still be in first by the time i had stopped.
[edit] i would still stop faster then you

if u used your rear brake on a non-slip clutch application,
and the rear left the ground
physics would tell me the engine would near stop,

feel free to correct me

Chrislost

12th August 2009, 16:59

The point about not changing down is valid. It's emergency braking, not slowing down for a corner. The few times I've had to emergency brake I've never bothered changing down, apart from the time when I had no front brakes in which case it certainly felt like changing down was slowing the bike faster than the rear brake was.

Changing down is automatic.
as is the rear brake, as is looking for a driveway/ditch/cliff to jump into/off

Chrislost

12th August 2009, 17:03

if u used your rear brake on a non-slip clutch application,
and the rear left the ground
physics would tell me the engine would near stop,

feel free to correct me
You are not wrong! I still dont know if my bike has a slipper clutch.

If the clutch was pulled in at this stage one could go bang bang bang and be in first, without the bike realising its still doing more than 0km/h
upon landing the back wheel back on the ground the bike would essentially bump start itself and be ready to go again

The Stranger

12th August 2009, 17:11

5metres can be the difference between contact with another vehicle or leaving the road.

Sorry, where did the 5m figure come from?

Chrislost

12th August 2009, 17:18

I will agree that back brakes do very little once the front end is compressed as rear becomes light but the initial effect of them scrubing off speed at the beginning of the braking makes a huge impact on the total stopping distance.
After all its the stopping distance that saves your life if you get in trouble.
5metres can be the difference between contact with another vehicle or leaving the road.

The most important thing that people are not mentioning in this thread is to use the best method every time you stop so that its second nature when you need it.There is a difference between knowing how and doing in a panic situation and I would back second nature before decision makers every time.

*****If you ride like you mean business then you will do the business when it counts.******

I love my rear brake. use it more then the front! the ammount of times it has saved my ass from hitting the pavement...!...
5m is fucking huge!!! more like .5 of a m between sweet and broken wrists...
***i agree***
If the mass was to stop the back lifting i would assume that one could stop faster as one wouldnt be flipping that stoppie...

mossy1200

12th August 2009, 17:28

I love my rear brake. use it more then the front! the ammount of times it has saved my ass from hitting the pavement...!...
5m is fucking huge!!! more like .5 of a m between sweet and broken wrists...
***i agree***
If the mass was to stop the back lifting i would assume that one could stop faster as one wouldnt be flipping that stoppie...
Every piece of additional weight that is above ground level still wants to go up and over the front because the pivit point is the contact patch of the front tyre on the road.Seeing as the front pivot point is where the stopping force is generated once the initial braking has begun then anything higher than that point is unwanted mass .

scracha

12th August 2009, 17:57

NDORFN

12th August 2009, 18:05

That's not a helpful view to take NDORFN. How do you propose people initially learn? Just by jumping on a bike and giving it a go?

Yes... that's exactly how I propose people learn. It's not just begginers either... anyone on an unfimiliar bike. Different techniques will work for different people on different bikes and the only way to find the most effective way is to experiment. There's only so many possible methods to braking... no one needs a lesson to figure them out, just this... "Here's the front brake lever, here's the rear brake pedal, there's some lines drawn at the end of your driveway... go nuts".

Chrislost

12th August 2009, 18:06

Every piece of additional weight that is above ground level still wants to go up and over the front because the pivit point is the contact patch of the front tyre on the road.Seeing as the front pivot point is where the stopping force is generated once the initial braking has begun then anything higher than that point is unwanted mass .

ever tried to do a stoppie with a pillion?

Chrislost

12th August 2009, 18:09

Yes... that's exactly how I propose people learn. It's not just begginers either... anyone on an unfimiliar bike. Different techniques will work for different people on different bikes and the only way to find the most effective way is to experiment. There's only so many possible methods to braking... no one needs a lesson to figure them out, just this... "Here's the front brake lever, here's the rear brake pedal, there's some lines drawn at the end of your driveway... go nuts".

the only way you can crash while braking is trying to turn or flipping it right over.
If the front locks FFS release the brakes a bit:doh:

Ixion

12th August 2009, 18:09

No, I never done a stoppie with a pillion.

But I done a stoppie with a woodie. And I done a pillion with my woodie.

Do they count?

NDORFN

12th August 2009, 18:16

the only way you can crash while braking is trying to turn or flipping it right over.
If the front locks FFS release the brakes a bit:doh:

Yeah good point... So after practising in the driveway you progress to this "Remember where the front brake lever is?. Remember where the rear brake pedal is? Now go around that corner until you can stop before you hit that concrete block I left in the middle of it"

scracha

12th August 2009, 18:16

As I said, they did some 800 emergency brake tests with a variety of riders - initially letting the riders do what they thought

They used about 7 riders and 2 motorcycles. Hardly a conclusive scientific experiement, and some of their results are at odds with much larger studies that you keep conveniently ignoring. I do however agree that changing down is generally a bad thing in an emergency stop (when a bus pulls out in front of you you normally don't even think about gears).

Before I became a "track day junkie/racer with LOTS of photos", I used about 90% braking force in the dry. I'm pretty certain that if the back brake slowed a motorcycle down more effectively then guys like Brian Bernard would know about it.

the only way you can crash while braking is trying to turn or flipping it right over.

bzzzzt...wrong. Lock up the front and quite often it wants to go one way or another. Roads have camber, bumps and one side of your tyre may experience a bit more grip than the other. Very hard to catch as well.

If the clutch was pulled in at this stage one could go bang bang bang and be in first, without the bike realising its still doing more than 0km/h

The DSA theory is to whip clutch in at the last minute (to keep engine spinning and utilise engine braking) and bang it down the gears. But you can theorise all day as from some of your statements I don't think you've actually done a real life emergency stop........

In real life (not practise or when I'm demonstrating an emergency stop), when some fucker has pulled out in front of me I ALWAYS stall the bike in whatever gear I'm in. My tiny foreign brain is more concerned about stopping in time or swerving to my escape route. Thus my original wiki point about once you've actually stopped, look behind you and if necessary throw bike to side and run like fuck.

Similar to my original wiki point about front vs back first not mattering because in an emergency, everyone hauls the front lever and stamps on the brake almost simultaneously anyway.

So really, aside from telling people to get in lots of practise and use both brakes (woops....both in my original wiki) then this whole thread has been pretty fuckin pointless.

p.dath

12th August 2009, 18:17

Yes... that's exactly how I propose people learn. It's not just begginers either... anyone on an unfimiliar bike. Different techniques will work for different people on different bikes and the only way to find the most effective way is to experiment. There's only so many possible methods to braking... no one needs a lesson to figure them out, just this... "Here's the front brake lever, here's the rear brake pedal, there's some lines drawn at the end of your driveway... go nuts".

If someone has already done 800 experiments for me do you think it is worth listening/reading what they have to say?

p.dath

12th August 2009, 18:20

They used about 7 riders and 2 motorcycles. Hardly a conclusive scientific experiement, and some of their results are at odds with much larger studies that you keep conveniently ignoring....

I'm not trying to ignore them - just no one has posted a link to them.

If you can tell me who did the much larger study I'll go find it on Google myself. I would be interested in any studies that were more extensive, or even of a similar size.

So what study should I search for?

Katman

12th August 2009, 18:22

No, I never done a stoppie with a pillion.

But I done a stoppie with a woodie. And I done a pillion with a woodie.

Do they count?

The pillion had a woodie???

:eek5:

The Stranger

12th August 2009, 18:24

If someone has already done 800 experiments for me do you think it is worth listening/reading what they have to say?

Therein lies the problem, 500 were excluded, and that is without being in an emergency situation.
How many would they have got right in an emergency situation?
I also note that they excluded a front brake only pass that was extrordinary, I guess it didn't meet their predetermined outcome.

mossy1200

12th August 2009, 18:27

ever tried to do a stoppie with a pillion?
The only thing that would prevent the stoppie would be lack of front tyre traction or inability of front discs and calipers to create enough drag.
And even though you have pillion(weight over the rear)are you claiming the bike will take less distance to stop.
The larger the total mass the more time it will take to stop given an equal applied force and traction ability of the tyre.
All weight higher than a pivot point wants to rotate on that point if you ask it to stop.When that force becomes greater than the gravitational pull it will move upwards.If you want your theory to work you need to increase the gravitational pull of the earth or extend the wheelbase of your bike so that the length of the pivot point increases so that gravity is stronger than the lifting effect(problem with this is the extended wheelbase will cause less front wheel traction and reduce front wheel grip,hence this is why cruisers get more assistance from rear wheel braking).:Offtopic:

Chrislost

12th August 2009, 18:30

The only thing that would prevent the stoppie would be lack of front tyre traction or inability of front discs and calipers to create enough drag.
And even though you have pillion(weight over the rear)are you claiming the bike will take less distance to stop.
The larger the total mass the more time it will take to stop given an equal applied force and traction ability of the tyre.
All weight higher than a pivot point wants to rotate on that point if you ask it to stop.When that force becomes greater than the gravitational pull it will move upwards.If you want your theory to work you need to increase the gravitational pull of the earth or extend the wheelbase of your bike so that the length of the pivot point increases so that gravity is stronger than the lifting effect(problem with this is the extended wheelbase will cause less front wheel traction and reduce front wheel grip,hence this is why cruisers get more assistance from rear wheel braking).:Offtopic:
nup.
im claiming that it FEELS HARDER to do said stoppie.

MyGSXF

12th August 2009, 18:31

So what study should I search for?

I would suggest you contact Andrew & Lynne @ www.roadsafe.co.nz & ask when they are running their next course in Ak.. get some professional training, from people qualified to teach you! :niceone:

Devil

12th August 2009, 18:31

... as most riders know to hold the tank with their knees

Unfortunately a lot dont know this, even those providing instruction at the N.A.S.S wednesday evenings...

NDORFN

12th August 2009, 18:31

If someone has already done 800 experiments for me do you think it is worth listening/reading what they have to say?

No. It'll only take you a few experiments to find the best fitting conlusions for you personally.

EDIT: Actually YES. I do think it's worth you listening/reading to what they have to say because you can never be too informed but I don't think it's something that should be presented as a conclusive article in Wiki because it's not necessarily applicable to all riders, on all bikes in all conditions and set up, in all road conditions.

Chrislost

12th August 2009, 18:32

The only thing that would prevent the stoppie would be lack of front tyre traction or inability of front discs and calipers to create enough drag.
And even though you have pillion(weight over the rear)are you claiming the bike will take less distance to stop.
The larger the total mass the more time it will take to stop given an equal applied force and traction ability of the tyre.
All weight higher than a pivot point wants to rotate on that point if you ask it to stop.When that force becomes greater than the gravitational pull it will move upwards.If you want your theory to work you need to increase the gravitational pull of the earth or extend the wheelbase of your bike so that the length of the pivot point increases so that gravity is stronger than the lifting effect(problem with this is the extended wheelbase will cause less front wheel traction and reduce front wheel grip,hence this is why cruisers get more assistance from rear wheel braking).:Offtopic:

hang on.
i failed physics, BUT
if i had 500N acting downwards at the back of my bike it sure would not lift upwards as easily as if i had 0N actuing downwards?
aka only when the pillion was directly above said pivot point would my stoppie be helped by said pillion

Disco Dan

12th August 2009, 18:34

So too sum up...

Don't listen to a dipshit or p.dath if you want to live.

mossy1200

12th August 2009, 18:36

hang on.
i failed physics, BUT
if i had 500N acting downwards at the back of my bike it sure would not lift upwards as easily as if i had 0N actuing downwards?
aka only when the pillion was directly above said pivot point would my stoppie be helped by said pillion
yes but the additional weight you have added to get the 500N is traveling forward with you towards a truck that pulled out from a driveway and now you have to reduce the speed of your very porky bike on the same tyres and brakes.Never mind cause what you cant achieve the truck will finish off for you.
increased mass = longer time to stop with an equal amount of force applied.

Ixion

12th August 2009, 18:39

The pillion had a woodie???

:eek5:

Hm. Perhaps I better rephrase that.

Devil

12th August 2009, 18:45

scracha

12th August 2009, 18:50

yes but the additional weight you have added to get the 500N is traveling forward with you towards a truck that pulled out from a driveway and now you have to reduce the speed of your very porky bike on the same tyres and brakes.Never mind cause what you cant achieve the truck will finish off for you.
increased mass = longer time to stop with an equal amount of force applied.

Gravity to make the 500N generally pushes the tyres harder on the ground giving them a greater friction co-efficient to partly offset the increased mass that has to be decellerated. Otherwise 40 tonne trucks would never come to a stop.

increased mass = longer time to stop with an equal amount of force applied.
True, but with the lard arse on your pillion you can apply the brakes (yes, I said brakes) harder before the tyres lock up.

mossy1200

12th August 2009, 19:05

Gravity to make the 500N generally pushes the tyres harder on the ground giving them a greater friction co-efficient to partly offset the increased mass that has to be decellerated. Otherwise 40 tonne trucks would never come to a stop.

increased mass = longer time to stop with an equal amount of force applied.
True, but with the lard arse on your pillion you can apply the brakes (yes, I said brakes) harder before the tyres lock up.
Dont have arguement with that other than the mass creating the 500N is above the axis point thus wants to revolve on that point during deceleration. Once this force gets greater than the 500N caused by gravity up and over it will want to go.By adding weight to the bike all this is doing is moving the central point of mass of the bike.Yes the point of stoppie(rotation)changes but so to does the formula of fixed mass decelaration against tractionable force(tyre) against maximum force capable of resistance induced by brake pads onto discs(drag).

I think my theory is correct therefore I will not be applying led weights to the rear of my motorcycle to reduce the stopping distance in an emergency as suggested earlier in the thread.
40 ton trucks have many large brakes and a huge contact patch.Weight in proportion to drag during decleration will give stopping distance.
I will admit having 18 wheels on your bike will reduce the time it takes to stop.

p.dath

12th August 2009, 19:15

Therein lies the problem, 500 were excluded, and that is without being in an emergency situation.
How many would they have got right in an emergency situation?
I also note that they excluded a front brake only pass that was extrordinary, I guess it didn't meet their predetermined outcome.

There doesn't seem any point in including lots of samples that took much longer to stop.

You are right that it was curious they did exclude the one front brake pass without a decent explanation. But that is only a single sample.

scracha

12th August 2009, 19:18

Yes the point of stoppie(rotation)changes but so to does the formula of fixed mass decelaration against tractionable force(tyre) against maximum force capable of resistance induced by brake pads onto discs(drag).

I wouldn't worry too much as on any modern sportsbike the maximum force of the brakes is waaay more than the tyre can cope with. Take a fat pillion out with you, you'll find you can brake VERY hard without locking up. Ignore the head-butting and crushed testicles though.

I'm not trying to ignore them - just no one has posted a link to them.

If you can tell me who did the much larger study I'll go find it on Google myself. I would be interested in any studies that were more extensive, or even of a similar size.

So what study should I search for?

I quoted you the bloodly text and gave you the name of the publication. Do you want the ISBN number too? Believe it or not, most academic studies are not published freely on the web. This lot took me all of 2 minutes to find.

Here...page 72.
http://books.google.co.nz/books?id=wqpNfKFlIuoC&printsec=frontcover&dq=riding+The+Essential+Skills#v=onepage&q=&f=false

I like this one. Especially how lane splitting is SAFER than having an arsehole driving too close to your rear tyre.

http://www.motorcyclecruiser.com/streetsurvival/0508_crup_emergency_braking_hurt_report/index.html

Page 26
http://www.dmvnv.com/pdfforms/dlbookmotorcycle.pdf

Page 82
http://books.google.co.nz/books?id=dlBunnjnvtcC&pg=PA82&dq=emergency+braking+motorbike#v=onepage&q=&f=false

Some more:

http://books.google.co.nz/books?id=2QAAAAAAMBAJ&pg=RA1-PA66&dq=emergency+braking+motorcycle#v=onepage&q=emergency%20braking%20motorcycle&f=false

Some good stuff in there about covering brakes when approaching junctions/intersections and flicking brake light on to tail-gators.

Disco Dan

12th August 2009, 19:18

ooooooh I can forsee a new episode of Mythbusters from this ! ! ! :chase:

utter pap this thread is turning into...

scracha

12th August 2009, 19:29

Huge list of references at the bottom of this one for ya p.dath

http://www.rospa.com/roadsafety/advice/motorcycling/info/motorcycling_safety_policy_paper_2006.pdf

TRL research12 shows that the incorrect use of motorcycle brakes is considered to be a factor in many motorcycle accidents. Over a third of riders used only the rear brake and 11% used only the front brake. Even in an emergency, 19% of riders only used their rear brakes and 3% only used their front one. One study estimated that correct braking, using the full braking capability of the motorcycle, could prevent 30% of motorcycle accidents, although this study was conducted before ABS was available for motorcycles.

The Stranger

12th August 2009, 20:06

There doesn't seem any point in including lots of samples that took much longer to stop.

Why then include 298 samples?
The 522 samples were excluded for not meeting the selection criteria i.e. the instructions given to riders weren't complied with - in a non emergency situation.
As noted, they were "experienced" riders - unlike yourself, what hope would you have th?.
You don't get to do it again once you just hit the concrete truck.

beyond

12th August 2009, 21:25

boomer

13th August 2009, 11:36

Pretty sure that they tell you this so that you dot get confused reaching for all the different leavers and knobs while that fkn car is pulling out in front of you.

EFFECTS OF DECELERATION FORCE
The mean deceleration for the group of 298 passes braking from 100 km/h to zero wa -0.898 g in a mean time
of 3.18 seconds. During these more than 3 seconds, the rider had to manage his braking while subjected to a considerable
deceleration force against his arms and hands which must in large measure support his upper body. A
simulator designed to recreate this force would have to incline the motorcycle on its front wheel at an angle of
64 degrees.

they obvoiusly used knob ends like boomer for their tests as most riders know to hold the tank with their knees

ahahhaa and you're a competent rider are you..??! how do you work that out then krasher...???! Bwahahhahahaha

FROSTY

13th August 2009, 11:36

Heres the thing guys n gals. EVERY situation is different. EVERY emergency presents issues in a different way.
I can without pause quote situations where heavy front end brakeing made use of the rear brake totally pointless
I can think of situations where less front brake meant the rear brakes efficiency was greatly increased.
I can think of bikes where the weight biase and brake setup mean you have to use both brakes to stop.

Add to that different bikes do indeed need the brakes applied in a different way.

That said The same basic principle still applies.
If you wanna stop --USE THE LOT

and practicing emergency braking on YOUR bike to find how IT stops quickest in ideal conditions is always a great idea.

p.dath

13th August 2009, 18:28

...
I quoted you the bloodly text and gave you the name of the publication. Do you want the ISBN number too? Believe it or not, most academic studies are not published freely on the web. This lot took me all of 2 minutes to find.

Here...page 72.
http://books.google.co.nz/books?id=wqpNfKFlIuoC&printsec=frontcover&dq=riding+The+Essential+Skills#v=onepage&q=&f=false

...

http://www.motorcyclecruiser.com/streetsurvival/0508_crup_emergency_braking_hurt_report/index.html

Page 26
http://www.dmvnv.com/pdfforms/dlbookmotorcycle.pdf

Page 82
http://books.google.co.nz/books?id=dlBunnjnvtcC&pg=PA82&dq=emergency+braking+motorbike#v=onepage&q=&f=false

Some more:

http://books.google.co.nz/books?id=2QAAAAAAMBAJ&pg=RA1-PA66&dq=emergency+braking+motorcycle#v=onepage&q=emergency%20braking%20motorcycle&f=false

The DSA reference on Google only goes up to page 33.

The motorcruiser article doesn't mention anything about braking first.

The dmvnv talks about using the rear brake.

The "How to ride a motorcycle" book also talks about using the rear brake.

The last article about BMW discusses their antilock braking system.

None of these articles contain research. They don't contain a more extensive study. And they don't support your premise that you shouldn't use the front brake before the rear brake.

They just discuss emergency braking in general, and pretty have similar results to the study I posted.

p.dath

13th August 2009, 18:36

The GSX1400 simply will not tolerate rear braking when stopping in an emergency or braking hard.

I've learnt from several sideways excursions into the shrubbery on my earlier blue and white 1400 that they do not like rear brake under heavy braking.

As R6_Kid pointed out, when braking hard on modern bikes of the sports or sports tourer style, the rear wheel is not in contact with the ground and therefore the rear brake is useless.....in fact... totally useless.
The 1400 throws a lot of weight forward when braking hard and therefore pulls up remarkably quick with front brake alone.

I have found out the hard way that the rear brake is good for low speed conditions, wet weather braking and hill starts but no good at any other times.
I now use only the front brake as this suits the bike perfectly and this bike can brake well into a corner and maintain a lot of grip.

There is no disagreement that once the weight has transferred onto the front wheel that rear wheel braking (or changing down) has hardly any impact (especially if your rear tyre is off the ground!).

And I don't think there is any disagreement that the rear brake is only effective for a very short time as a result. I think from memory it reduced the stopping distance by another 3m to 4m from 100km/h.

The only real question is weather applying the rear brake at the beginning of the exercise produces a shorter stopping distance.
Perhaps if it is sliding sideways too much rear brake was being used?

p.dath

13th August 2009, 18:38

Why then include 298 samples?
The 522 samples were excluded for not meeting the selection criteria i.e. the instructions given to riders weren't complied with - in a non emergency situation.
As noted, they were "experienced" riders - unlike yourself, what hope would you have th?.
You don't get to do it again once you just hit the concrete truck.

They were trying to test stopping in the shortest distance, so obviously you want to exclude those cases where the stopping distance was much longer.

They also examined which *factors* lead to a shorter stop. So obviously once you are down to that stage it doesn't make sense to consider a stop that doesn't involve that factor.

FROSTY

13th August 2009, 18:44

The DSA reference on Google only goes up to page 33.

The motorcruiser article doesn't mention anything about braking first.

The dmvnv talks about using the rear brake.

The "How to ride a motorcycle" book also talks about using the rear brake.

The last article about BMW discusses their antilock braking system.

None of these articles contain research. They don't contain a more extensive study. And they don't support your premise that you shouldn't use the front brake before the rear brake.

They just discuss emergency braking in general, and pretty have similar results to the study I posted.
iN A NUTSHELL DUDE THAT STUFF IS EXACTLY the issue I see with KB at times.
Quote a bunch of articles and stuff without actual personal experience.

If I can find it I will dig out a well researched article that tells you the best way to avoid an accident on a bike. It goes into detail on the best way to lay your bike down so it slows smoothly and with minimum damage on its side. And you know what Im (just) from the generation where that information was actually true.

p.dath

13th August 2009, 18:52

mossy1200

13th August 2009, 21:36

One thought does come to mind with doing stops from high speed (say 200Km/h+) on a track compared to 100km/h on a road.

I think everyone agrees that the rear break can only have an effect for a short period of time until the weight moves to the front tyre.

If you consider stopping from 200Km/h. Lets pretend that takes 6s. Lets pretend the rear brake had an effect for 0.5s. That would mean the rear brake would only have an effect for 8.3% of the manoeuvre. However I'm guessing that at higher speed their will be far more momentum pushing weight on the front tyre (momentum = mass times velocity). So the 8.3% could be much smaller.

The study found the average braking time from 100Km/h has a tad over 3s. Lets pretend the brake still only had an effect for 0.5s. That now equates to 16% of the time.

I'm wondering if track riders don't bother with the rear brake as much (if at all) because the perception of the amount of time that it makes any difference is so much smaller.

So I'm wonder further if perceived impact of rear braking is greatly affected by the speed you start your braking from.
Correct the rear brake has most effect while bike is squatting then as the rear becomes light the rear has less effect(but still some).
The thing is in an emergency stop the idea is to cut speed quick and as the initial braking is at the highest speed the distance travelled is greater.Therefore as far as distance to stop goes the initial braking and reaction time has the most effect on the stopping distance.
Reaction time is a huge factor.Those who ride casual and not scanning ahead for possible danger have very slow reaction to threats.
If you are scanning for danger you are ready to act.