Emergency braking

[Katman]

All this talk of emergency braking has missed the fact that the first split-second decision that has to be made is "Can I stop in time?"

If you decide you can, then by all means use the brakes in whatever manner you have found works best.

If you know you can't stop in time, less force on the front brakes allows you some ability to steer around the obstacle.

[Jonno.]

All this talk of emergency braking has missed the fact that the first split-second decision that has to be made is "Can I stop in time?"

If you decide you can, then by all means use the brakes in whatever manner you have found works best.

If you know you can't stop in time, less force on the front brakes allows you some ability to steer around the obstacle.

Yes but you can unload your brakes half way through, you can't un-not brake half way through.

[ZX12R Hoon]

because it increase your stopping distance, that's why you shouldn't.
in my opinion we'll have to clearly declare which is the question: do i have to COME TO A STOP or do i have to AVOID the obstacle?
in the first case, you have a wall in front of you. there's no "escape" after: you were dumbly lookin at how your tank shines then up your eye and find a 18 meter truck exactly in the middle of the lane. there you have to stop, no question. in the second, a car suddenly stops in the middle of the lane and turn without the indicator: in that case you can avoid it, and in that case i'd probably use very little the front brake, cause stopping is not my first option (different would be if you have a truck coming in front of you on the other lane...)

so if you want to stop, the right gear at the end is completely unuseful, while the engine will continue to drag you ahead and you cannot be focused on the front wheel:
http://www.fmq.qc.ca/pdf/amorce-freinage_eng.pdf

and about stopping in less space than a car, who said that?
http://www.monteverdiclub.com/rahmen/stoptbl.htm
to me seems equal.
and maybe there's much more cases in which the car stops in less space, cause the bike is often faster in the traffic flow. it's true, the bike is lighter, but it has less tyre surface on the ground, it has more weight transfer, often faster pace and in the most cases no brakin assist.

with what data are you saying bikes stops shorter?

My experience is that they do, if the rider uses correct braking technique, if they just use the rear theres no way the bike will stop first, it's also unrealistic to talk about different speeds when comparing, to make any discussion valid we all need to agree that we are talking equal speed, same surface. Of course different bikes brake differently but in general with modern bikes with disk brakes I would be fairly sire that a bike will stop faster.

Try this sometime, go out to a car park, get some speed up, clutch in and then brake fairly hard with both brakes, if the rear doesn't skid I'd be really surprised. Why? Because the weight has transfered to the front and the rear has very little traction, it skids. Now, if it can skid with the brake you already have more braking effect than you can use, there's no point in retaining engine braking. It's better to keep the clutch in because when the back wheel stops the engine stalls if it's out and you lose the possibliity of having an escape mechanism.
I agree with other posters that there is a danger of locking the front and that's why it's important not to lock the rear, a lot of modern bikes have massive braking on the front, the wheels keep you upright when they are rotating so it's better to keep the rear rotating just in case you lock the front because it will keep you upright until you get a bit of braking off the front and get back in control.
Remember, we are talking about an emergency situation here, of course in a normal decelleration into a corner where you want to bleed off a bit of speed you use engine braking. This is different, it's all about gaining EVERY advantage to tip the balance your way. An extra meter of travel can easily be the difference between going home for a beer or going to hospital, take every advantage you can gain.

[Urano]

it is by sure my bad bad english, so i want to say clear it once for all, just not to be misunderstood:

i NEVER said to use the rear brake only if you want to stop the bike.

there's no way to stop a bike using the rear only, unless you have a LOT of space, someone back on the saddle, and you want to be VEEERY smooth.

the reason why modern bikes have massive brakes on the front is right because it's there that they are needed.
the rear brake is useful (quite) only to correct your path in a turn, if you want to slow down more quickly than with the engine only (in particular if you have a 4 c or a 2 stroke), and as we are saying here, to weight up the front fork and give the front wheel a bit more friction on the ground.

as for keeping the rear wheel rotating to keep you upright if the front would lock, well, in my opinion it doesn't work.
it would work if you were going backward: and that's why you should always use the uphill brake to stand still when you are not in plane. you can try it on your garage ramp.
in normal conditions, going forward, if you'll lock the front during an emergency brake, with the whole weight of the bike on the front fork, the rear one will not be sufficient...

[Metastable]

If you lock the front you need to release the brakes a bit, but very quickly.... but you can go for a very small period of time with the front wheel locked.

Now, I was reading Cycle Canada. During the new Hayabusa launch in Atlanta, they were on the highway heading to the track and Jason Britton would hammer on the front brake and lock it on purpose while keeping the throttle pinned and basically do these incredibly long front wheel skids going down the highway. Disclaimer -> Peeps, don't try that!!!!

[Urano]

yaaa... now that i thing better on it, it is also possible to make a wheelie lockin the front wheel...
so, about the thing that the rear wheel alone would not be sufficient to keep you right, well, i've said crap...

the substantial difference that make it true is probably that on a wheelie (and maybe in that demonstration you've seen, in composition with the speed vector) the great part of weight is on the back wheel, while on an emergency brake the whole weight is on the front one.
it is still true also that if you lock the rear you could sign the ground with the tyre, if you lock the front you'll probably sign it with the nose...

[ZX12R Hoon]

There's another point to make about correct braking. Many bike riders like to go for rides with mates, we group ride. A few years back some fellow Club members were out on a ride. Clive and Pat were in the group enjoying the ride when a situation suddenly developed which meant Clive had to brake quite hard. Another bike travelling behind them two-up came in and hit really hard, everyone came off and had injuries, both bikes written off and Pat, well she will never physically get over it, she has had years of pain and is facing the rest of her life with pain. Taking about the crash at some point it came up that the rider of the bike that hit them had never used the front brake, he was worried that the front may lock so in his mind it was safer to use the rear, he had ridden for years doing that.
My point is that it's your responsibility to learn how to brake properly. If you are riding in groups you don't want either to hurt one of your mates or be hurt by one of your mates. Just think about spending the rest of your life in constant, debilitating pain simply because a riding mate couldn't be bothered to learn an important part of riding, probably the most important part.
Any mug can get on a bike, get it rolling forward, and go fast down a straight road, but it takes some time and concious effort to learn how to stop it properly.

[Katman]

My point is that it's your responsibility to learn how to brake properly. If you are riding in groups you don't want either to hurt one of your mates or be hurt by one of your mates.

Which is precisely why, when talking Emergency braking, the learning of avoidance techniques while braking becomes every bit as important as stopping in the minimum distance possible.

Not much good getting the maximum stopping power out of your front brake if in the process it still means slamming into the back of whoever is in front of you.

[slofox]

Had the chance to put all the above into practice this morning...a genuine emergency braking situation...

Heading downhill, straight road, with an apparently uninterrupted view all the way to the distant corner ahead.

Pulled out to overtake a slow car. Not realising that there was in fact, a dip in the road that effectively concealed a car coming the other way. Get out to overtake and this car appeared - too close to complete the overtake. Had to chuck out the picks and try to pull back to my own side of the road. Mission achieved but needed a deep breath to still the adrenalin rush. No doubt convincing both car drivers of the total idiocy of all bikers..."no wonder they have so many bloody crashes didja see that fool? Wadda dork!"

ooops.


EDIT: Oh and don't ask me how I used the brakes - I have no idea...

[Bad Gixxer]

Hi, this is my first post so I hope I don't offend. I've been riding for 30 years, done some racing, and always ride a bike like I stole it. I've read all of this thread and it seems to me that there is some confusion over "braking" and "slowing". Braking is how you apply either your right hand and/or your right foot to the appropriate levers. It seems that much of the discussion in the thread relates to this, although one or two have mentioned disengaging the clutch to stop the engine from carrying on forward momentum.

My advice is don't think "brake", instead think "slow down and avoid". My logic for this is that if you simply apply your brakes in an emergency situation with the intention of bringing your bike to a standstill (regardless of the braking technique), then you're going to travel in a straight line towards the obstacle - you may stop in time, you may not.

However, if you think that I need to slow the bike down as much as possible (possibly to a standstill), and then take evasive action, the chances are that you'll come out much better off. Hell, the evasive action might be to recognise that you aren't going to stop and/or avoid the obstacle in time, get on the balls of your feet and try and jump off the bike and over the obstacle rather than hit it (not entirely practical on a Harvey Donaldson, but entirely practical on a GSXR1000).

As to the "slowing technique", I advise everybody to get on a quiet road or a track day and SERIOUSLY practice different techniques. Each bike is different, we all have different suspension settings, we all weigh differently, we all have different fear factors. My technique is to ALWAYS ride with a finger covering the front brake, NEVER use the rear brake, ALWAYS preload the front brake through throttling off and applying slight pressure before applying full pressure, ALWAYS change down gears rapidly (using blipping) at the same time as braking, ALWAYS be prepared to release the brake to allow you to steer around the obstacle, or lean into the curve, ALWAYS believe that applying your brake/s is just one option available to you to avoid an obstacle.

Engine braking is seriously underutilised by many sportsbike riders. If you can learn to brake heavily with one (or two) fingers, while changing down rapidly through the gears using blipping, then this is a much better alternative to using the rear brake. Watch the MotoGP riders as they approcah the end of the straight into tight bend - NO rear brake, TONS of front brake, rapid gear changes, back wheel hardly touching the ground (if at all). The rear brake is not really a useful tool if your rear wheel is barely touching the track.

[george formby]

Had the chance to put all the above into practice this morning...a genuine emergency braking situation...

Heading downhill, straight road, with an apparently uninterrupted view all the way to the distant corner ahead.

Pulled out to overtake a slow car. Not realising that there was in fact, a dip in the road that effectively concealed a car coming the other way. Get out to overtake and this car appeared - too close to complete the overtake. Had to chuck out the picks and try to pull back to my own side of the road. Mission achieved but needed a deep breath to still the adrenalin rush. No doubt convincing both car drivers of the total idiocy of all bikers..."no wonder they have so many bloody crashes didja see that fool? Wadda dork!"

ooops.


EDIT: Oh and don't ask me how I used the brakes - I have no idea...

I have done that twice in the last few months, had room to shoot the gap both times but I felt like a complete squid & deserved any vitriol from the drivers. Sorry! Ok, back to brakes.

[p.dath]

Hi, this is my first post so I hope I don't offend. I've been riding for 30 years, done some racing, and always ride a bike like I stole it. I've read all of this thread and it seems to me that there is some confusion over "braking" and "slowing". Braking is how you apply either your right hand and/or your right foot to the appropriate levers. It seems that much of the discussion in the thread relates to this, although one or two have mentioned disengaging the clutch to stop the engine from carrying on forward momentum.

I personally draw a distinction between emergency braking (where you are trying to brake to save yourself injury), and brake and escape, where you are trying to reduce speed and have a potential escape avenue.

This particular thread was specifically about emergency braking - where there isn't an avenue of escape (I do accept that you can't always plan your escape immediately).

And because I have particularly thick skin, I wrote a blog article on the matter:
http://www.kiwibiker.co.nz/forums/en...rgency-Braking

Your experience vastly exceeds mine; but I do at least one thing differently to you and perhaps it's a matter of style. I don't ride permanently covering the front brake. Sure if while looking ahead I see something that makes me concerned I'll cover the front brake, but otherwise no.

[Smifffy]

EDIT: Oh and don't ask me how I used the brakes - I have no idea...

I tend to agree with this bit to an extent. There are a limited number of inputs you have, eg front/rear brake, clutch, throttle,steering etc. There are a number of permutations of these in combination. It is excellent to make a practised study of the way these inputs can be combined and the response you get from the bike. In a real life situation, the bike will respond to the inputs applied in real time providing instant feedback. Knowledge and experience, gained through riding your motorcycle, and lots of practice in applying the inputs, should inform you of exactly which input needs to be applied for the bike to respond the way you want it to.

Get out and ride

[Bad Gixxer]

but I do at least one thing differently to you and perhaps it's a matter of style. I don't ride permanently covering the front brake. Sure if while looking ahead I see something that makes me concerned I'll cover the front brake, but otherwise no.

Hey your blog is particularly useful and certainly shows that there are a lot of recommended braking methods around the world. I'm not saying that the way I do it is the only way or the correct way, but it works for me. I'm sure you'd agree that all riders should practice different methods to determine what works best for them and for their bikes. However on the issue of having a finger covering your brake at all times...I would SERIOUSLY recommend that you try this out, even when going around a curve. You'd be amazed at how much more effective and smooth the braking is when you eliminate the reaching/grabbing effect - it especially works well when you apply slight preload pressure before full pressure. I've done tests where the stopping distance can be improved by 30% just by having the brake covered and applying preload. In an emergency situation, eliminating that half second delay in braking will make a big difference. (It also saves demerit points when you spot the cruiser in the nick of time.)

[p.dath]

Hey your blog is particularly useful and certainly shows that there are a lot of recommended braking methods around the world. I'm not saying that the way I do it is the only way or the correct way, but it works for me. I'm sure you'd agree that all riders should practice different methods to determine what works best for them and for their bikes. However on the issue of having a finger covering your brake at all times...I would SERIOUSLY recommend that you try this out, even when going around a curve. You'd be amazed at how much more effective and smooth the braking is when you eliminate the reaching/grabbing effect - it especially works well when you apply slight preload pressure before full pressure. I've done tests where the stopping distance can be improved by 30% just by having the brake covered and applying preload. In an emergency situation, eliminating that half second delay in braking will make a big difference. (It also saves demerit points when you spot the cruiser in the nick of time.)

I've tried a number of grips myself. With normal riding when there is nothing making me concerned I ride with all fingers on the throttle. Otherwise I use my left two fingers on the brake, and my right two fingers on the throttle.
I've found this provides me with the best balance of braking and throttle control. I end up using this style to make blipping down easier.

You'll find another large school of thought that says you should have all fingers either on or off the brake. This can especially have an impact under emergency braking with those people that don't engage the clutch straight away, as you run the serious risk of driving the engine against the brakes when you have some fingers on the throttle and some on the brake.