Emergency stop practice - gear change problem [Archive]

robertvi

6th March 2010, 23:27

robertvi

6th March 2010, 23:42

sudden "brain wave": do I need to wheel the bike backwards to fix this?

TimeOut

7th March 2010, 05:31

sudden "brain wave": do I need to wheel the bike backwards to fix this?

Yep, moving back and forward will help. Bike gearboxes are sequential not like cars
Try to change down while still moving, if it's real bad try shutting the bike off and rock it with the clutch engaged.

Don't apply too much force to the gear leaver as that can do damage.

CookMySock

7th March 2010, 07:06

90% of your sudden braking is completed 50% into the manoevre, so you get time to sort the gears out. The small percentage of the time (microscopic) where you are forced to a stop in a high gear is an inconvenience you will just have to reconcile. ;)

Steve

scracha

7th March 2010, 07:26

Being a noob I've been practising emergency stops on some back roads near my house. This type of stop obviously dispenses with engine breaking and down shifting

Why "obviously". Yes, the most important thing is getting to a stop safely and quickly. However, You should also keep your fingers off the clutch lever to take advantage of engine braking (also keeps the bike a bit more stable) and in a perfect world pull it in at the last minute and bang it down the gears.

In "real life" you'll shit your pants, lock up both wheels, come to a stop in 6th and stall the engine LOL. Make sure you check what's around you after a real life emergency stop and if necessary push the bike or simply get off it and run like fuck. I can't stress this last point enough; you may have spotted the hazard and pulled a beautiful emergency stopp(ie) but the myoptic 4x4 driver up your arse might not be so perceptive.

Getting it back in gear. Wot Timeout said was spot on.

See the "braking" thread where I'm correct, and most of the other posters are not (sic). I think there was something on the Wiki but the oversealous Nazi Mods erased it.
http://www.kiwibiker.co.nz/forums/showthread.php/107722-Braking
http://www.kiwibiker.co.nz/forums/showthread.php/105129-Emergency-Braking

robertvi

8th March 2010, 12:05

Thanks! I'll try rocking it back and forth next time if I'm stuck again. And good to know that engine breaking can still be of some use in this situation.

slofox

8th March 2010, 12:21

This type of stop obviously dispenses with engine breaking and down shifting, .

No it doesn't. Well, not for me anyway. I find that I downshift whilst braking during an emergency stop without even thinking about it. I must have learned to do this centuries ago 'cause it always happens. I prefer to use every bit of braking available in an emergency stop. Which includes engine braking.

cowboyz

8th March 2010, 12:42

actually.. me too. In any emergency stopping I find myself flicking through the gears by default before I even start braking. Then its all over the front and remmebering there is a rear in there somewhere. I drive on the gearbox alot anyhow. (and yet I dont seem to find the urge to rev the shite out of my bike on a downshift)..

sleemanj

8th March 2010, 16:05

Clutch when emergency braking, two schools of thought, first is that not clutching will allow you to use the engine to brake the whole time, second is that not clutching won't allow you to downshift easily so your engine braking is limited to whatever gear you are in. Engine braking contributes little to an emergency stop anyway I expect so either way, just make sure you are on the brakes.

Changing gear when you've stopped in a high one, you'll get the hang of it, but just use the clutch to "click" it into gear, hard to explain since it's a bit instinctual, but with clutch in, put pressure on the gear shift like you're trying to change, and slightly release the clutch, it should click in, a slight rock back/forward may help if it's stubborn. Without the engine running, rocking is required.

Also occasionally you might hit a false neutral when shifting up if you don't quite catch the gear, usually in front of a load of people as you try for that uber cool take off, also pretty normal, bike gearboxes are finicky beasts.

Mom

8th March 2010, 16:28

Being a single pot engine the GN actually has reasonably good engine braking, infact is is really easy to compression lock the rear wheel if you drop it into 1st and let the clutch go quickly. Good fun if you are just turning into your driveway :innocent: but can be disasterous if you manage to do it around a corner. I would encourage you to start to practise engine braking in conjunction with your (hopefully) progressive emergency braking. Anything that is going to slow you down faster has got to be good.

slofox

8th March 2010, 16:42

Engine braking contributes little to an emergency stop anyway

Mmmm...it sure feels like it does to me. Got any links regarding this at all? Might be interesting to compare stoppping distances with and without change-downs. Must try it one day...

p.dath

8th March 2010, 16:49

Lets just say that emergency braking technique is highly contentious, and there is considerable disagreement over the use of things like the clutch.

Personally, I feel the answer depends on the speed you are commencing the emergency braking manoeuvre from. I present for your consideration this study:
http://www.fmq.qc.ca/pdf/amorce-freinage_eng.pdf

Emergency braking on the track from high speed is very different from emergency braking on the road from 100km/h, because of how quickly the weight shifts from the rear to the front tyre.

My personal opinion, if you are emergency braking from 100km/h or less, engage the clutch. Forget engine braking. Engage the rear brake, shortly followed by the front brake. The study above explains it well.

If you were doing it from 200km/h on the other hand, I'd tell you to forget the rear brake altogether. Because the load transfers so fast onto the front wheel that only the front brake is effective. For this same reason I feel that engine braking has a limited impact (remember, this is emergency braking). Once the weight has come off the back wheel then using the back wheel to slow down the bike has little impact.
On the track engine braking may be used more - but that is because you want drive out of the corner, and not just achieve maximum stopping power. On the track you only want to effect a rapid decrease in speed, but never to a speed of zero.

I now sit back and put on my flame suit.

EDIT: Upon reflection, I think engine braking into a corner on the track is more involved. I think it has some impact to overall speed, but I think it has more uses than just speed alone. But I still hold that I think engine braking is of limited use when braking from 100km/h on the road in an emergency situation.

slofox

8th March 2010, 16:51

is really easy to compression lock the rear wheel

Yeah. I've done that under emergency braking as well...:whistle:

Mom

8th March 2010, 18:27

Yeah. I've done that under emergency braking as well...:whistle:

I remember doing it for the first time on a GN. I was following my lovely man, he decided to turn off the highway at VERY short notice. I was barrelling along and had to um...
slow down quickly :pinch: so I could make the turn and not overshoot and have to travel a kilometre up the road before I could safely turn around. The rear wheel locked and went all sorts of sideways :D Shit oh dear! It had been so long since that had happened to me. :rockon:

After that, I used to deliberately lock the rear wheel as I started to turn into our driveway :innocent:

You dont get too much fun on a GN, you have to take every opportunity it presents :yes:

Tryhard

8th March 2010, 21:04

Engage the rear brake, shortly followed by the front brake.

The rear first? is that for real?
I think I maybe practising the wrong way!

scracha

8th March 2010, 21:16

Engage the front first, followed almost instantly by the rear.

Lets just say that emergency braking technique is highly contentious, and there is considerable disagreement over the use of things like the clutch.

Yep. As per usual I pretty much disagree with most of what p.dath is saying. As usual I'm going by my own experience and DSA UK guidelines produced after considerable research by chaps far more learned than I. P.dath is yet again relying on one little study based on a handful of riders and a tiny amount of testing.

Regardless of of differences, most importantly go out and practise. See what feels better and stops you quicker.

p.dath

9th March 2010, 10:24

Engage the rear brake, shortly followed by the front brake.

The rear first? is that for real?
I think I maybe practising the wrong way!

The rear brake is only of use while there is weight on the rear wheel. As soon as that weight is gone the rear brake is of little use (I think even scracha will agree with me on this one ...).

As soon as you apply the front brake hard the weight will rapidly transfer onto the front wheel.

Now this is where people's opinion will vary, and this is most definitely my opinion. You should consider what different people say, and come to your own conclusion.

Dis-engage the clutch and apply the rear brake immediately. Briefly stablise the bike and yourself on the bike if needed (and I mean briefly), and then get on the front brake hard. Re-adjust the front brake pressure as needed.

EDIT:
Just read scracha's reply,
Engage the front first, followed almost instantly by the rear - so we are in complete disagreement. :)

p.dath

9th March 2010, 10:50

This appears to the the DSA guidelines (from the UK) for an emergency stop:

http://www.bikerforum.co.uk/forums/new-rider-information/2708-performing-emergency-stop-motorcycle.html

The Emergency stop tests your reactions and ability to stop the bike at speed as quickly and safely as possible. It is generally taught as a 5 point system.

1. Shut off the accelerator.

2. Apply the front brake.

3. Apply the rear brake.

4. Increase the pressure on the front brake.

5. Apply the clutch to avoid stalling (on a manual).

Once again, it makes little sense to me to apply the rear brake once the weight has been removed from it. The numbers in the study I sighted are still the best evidence I have seen. Someone actually measuring it.

Until I see a better study, I will be holding to it.

Coldrider

9th March 2010, 11:04

centaurus

9th March 2010, 11:06

After extensively practicing emergency braking and normal braking with and without clutch, I have found a middle way: First start braking with the clutch engaged to take advantage of the engine braking. If it's a normal braking I will go down through the gears but if it's an emergency one I don't (saves time). Once the revs do quite low on the engine, I pull the clutch in to prevent stalling (engine braking at that point is quite low anyway). Dependin on the engine, the cut-off point is different. For an inline4 like mine, once the bike goes below 2-3k rpm it's useless, for your GN, even in top gear, engine braking should be good up to 1k rpm (or close by).

If you pull the clutch in when you start braking, you will not slow down as fast as with the clutch engaged and the risk of locking the rear wheel is quite high.

If you shift down through the gears you either blip the throttle which will reduce your breaking (you will inadvertedly slightly release the front brake lever while working the throttle) or don't blip in which case it's bad for the transmission and you risk locking the rear wheel and dropping the bike.

Try emergency braking (in a parking lot) with and without the clutch and see which one feels better and stops the bike faster.

As for gear changes issues, some bikes are worse than others - I've had my share. A few things that work: if you are standing still, try slightly engaging the clutch. That will move the gearbox cogs just enough to make it work again, or you can just move the bike forward/backwards. If you are moving and the revs of the engine are too high or too low for the speed and gear you are trying to engage, even with the clutch fully pulled in, some bikes will not go into gear. Some gearboxes just do nothing, other will push back the gear changer pedal (you can feel it on your foot). If that is the case the revs need to match the speed and gear.

Crasherfromwayback

9th March 2010, 11:23

I scored a trackday coached by Brian Bernard and Freddy Merkel back in 2001.
Upon learning emergency stopping procedure it was front brake only, learnt how to do stoppies at the same time.
If there is a KBer who is World Superbike Champion more than twice they may correct me.

Fred Merkel was indeed a great racer. But just because he doesn't use the rear brake doesn't mean you can't or shouldn't. Ever seen the size of the rear disc on Nicky Haydens bike?

Nicky Hayden...you know...the guy that beat Rossi for the world title!

Coldrider

9th March 2010, 11:29

Fred Merkel was indeed a great racer. But just because he doesn't use the rear brake doesn't mean you can't or shouldn't. Ever seen the size of the rear disc on Nicky Haydens bike?

Nicky Hayden...you know...the guy that beat Rossi for the world title!I knew Carl Fogarty would turn up sooner or later.......just kidding.
It is really about personal preference, what your mind and body does instinctly in the situation.
When the back wheel is 600mm of the deck and your mind is on keeping the forks compressed and front wheel almost locked, a little rotation and a bit of smoke, how do you have the mind to work on the back brake, that is off the deck?

centaurus

9th March 2010, 11:35

Fred Merkel was indeed a great racer. But just because he doesn't use the rear brake doesn't mean you can't or shouldn't. Ever seen the size of the rear disc on Nicky Haydens bike?

Nicky Hayden...you know...the guy that beat Rossi for the world title!

Depending on the bike type, there might be more or less weight on the rear wheel, which determined the ammount or rear brake you whould be using. On sport bikes most of the weight is on the front (about 10% of the braking is on the rear). Some people use the rear to compress the front and as they progressively squeeze the front lever more, the reduce the rear brake pressure (progressively also). The more front brake you have the less pressure the rear wheel has on the ground and the risk of locking the rear is higher. Also, you need to remember that rear brake is mainly used on sport bikes for slowing down or leaning more mid corer for those situations when you realise mid corner you have too much speed. for that alone and a bid rear brake is helpful at racing speeds.

Mathematically speaking using the rear brake too will add almost 5-10% more braking power but the risk of locking the rear being so hight, most people do not use the rear when emergency braking. If you are good enough to REALLY be sure you won't lock the rear, go ahead and use it, but if in doubt, 5-10% (for sport bikes) procent less braking power is a price most people would gladly pay in return for canceling a high rist of rear wheel locking. It's a matter of personal choice, based on how much experience do you have and how much you know your bike. Nobody can tell you if you should or shouldn't be using the rear brake in an emergency braking.

Of course, when talking about other types of bikes that have more weight on the rear, the situation changes drastically: on some bikes you can go up to 40% braking power on the rear in which case you simply can't ignore the rear brake.

dipshit

9th March 2010, 11:37

When the back wheel is 600mm of the deck and your mind is on keeping the forks compressed and front wheel almost locked, a little rotation and a bit of smoke, how do you have the mind to work on the back brake, that is off the deck?

In the first initial part of the braking - your back wheel will not be in the air. You are dreaming if you think it will be.

Coldrider

9th March 2010, 11:39

In the first initial part of the braking - your back wheel will not be in the air. You are dreaming if you think it will be.The idea is to get the back wheel off the deck.

dipshit

9th March 2010, 11:41

The idea is to get the back wheel off the deck.

The idea is to stop as quickly as possible.

howdamnhard

9th March 2010, 11:41

I agree with centaurus and p.dath regarding emergency braking. In a true emergency stop situation I don't have time to engine brake. Rear brake helps initially but loses traction as weight comes off rear wheel. I don't even bother about rear near the end and concentrate soley on not locking the front. Pulling the clutch prevents stalling the engine and allows you to get out of the way(been there and done it). If you have too stop relatively quickly but not use emergency stop then I use downshifting of gears. If you should inadvertently lock up the rear(by downshifting to far) just pull the clutch in to regain control.
Sometimes the bike needs moving slightly to get the gears to engage. My GN used to not like changing to nuetral from first if stopped,used to let the clutch out slightly and let it creep forward and then it would normally engage. My ZZR sometimes does it as well.

Coldrider

9th March 2010, 11:44

The idea is to stop as quickly as possible.Correct, that was the purpose of that particular lesson.

Crasherfromwayback

9th March 2010, 11:49

Depending on the bike type, there might be more or less weight on the rear wheel, which determined the ammount or rear brake you whould be using. On sport bikes most of the weight is on the front (about 10% of the braking is on the rear). Some people use the rear to compress the front and as they progressively squeeze the front lever more, the reduce the rear brake pressure (progressively also). The more front brake you have the less pressure the rear wheel has on the ground and the risk of locking the rear is higher. Also, you need to remember that rear brake is mainly used on sport bikes for slowing down or leaning more mid corer for those situations when you realise mid corner you have too much speed. for that alone and a bid rear brake is helpful at racing speeds.

Mathematically speaking using the rear brake too will add almost 5-10% more braking power but the risk of locking the rear being so hight, most people do not use the rear when emergency braking. If you are good enough to REALLY be sure you won't lock the rear, go ahead and use it, but if in doubt, 5-10% (for sport bikes) procent less braking power is a price most people would gladly pay in return for canceling a high rist of rear wheel locking. It's a matter of personal choice, based on how much experience do you have and how much you know your bike. Nobody can tell you if you should or shouldn't be using the rear brake in an emergency braking.

Of course, when talking about other types of bikes that have more weight on the rear, the situation changes drastically: on some bikes you can go up to 40% braking power on the rear in which case you simply can't ignore the rear brake.

Yeah...each to their own. Bruce Ainstey uses quite a bit of rear brake...I don't and was able to regularly out brake him. What ever suits the individual best is the best way.

howdamnhard

9th March 2010, 11:52

The idea is to stop as quickly as possible.
Agreed ,precisely.

dipshit

9th March 2010, 12:19

Correct, that was the purpose of that particular lesson.

I know. I had a training day with Brian Bernard early last year while on my SV1000. He was still teaching the front only technique to the wide range of bikes present.

My shortest stopping distance was my first run when I used both brakes in my normal fashion. The last part of it had the rear end off the ground as it came down with a thud when I stopped.

Several front only runs overshot my first mark.

Granted my GSXR feels different in regard to using the rear brake. It feels like using the rear brake on the 600 lifts the back of the bike rather than squats the rear end down like it did on the SV. I need to do some more good stopping practice on my 600. I will go by what works and feels better for me rather than just go by what someone said.

george formby

9th March 2010, 12:48

Touch wood, it has been a while since I had to throw out the anchor, last time was in the rain braking from 70mph ( I know...). Gotta love modern tyres.
I instinctively use front brake first, cover rear brake pedal & change down, releasing the clutch between changes. I use the rear brake when it has good road contact. To early & it is very easy to get the back sliding, a bit to much to think about in at emergency. The rear may supply the last bit of braking needed to avoid an off but I think it is only really effective when a lot of speed has been scrubbed off. Also depends on the style of bike, more effective with a cruiser.
For a few years now I have followed some advice from a Police motorcycle instructor, always be in the right gear. Around town that would be 2nd or 3rd. Grabbing a big handful of brake at 50kmph is going to stop you pretty quickly but still allow time for at least one down change. As Scratcha ( I think ) said, it's whats behind you that might get you. If your riding round town in 4th you cannot accelerate quickly to avoid trouble & keeping the bike in the appropriate gear under emergency braking is nigh on impossible. Try a lower gear round town, it really helps.

p.dath

9th March 2010, 12:57

I scored a trackday coached by Brian Bernard and Freddy Merkel back in 2001.
Upon learning emergency stopping procedure it was front brake only, learnt how to do stoppies at the same time.
If there is a KBer who is World Superbike Champion more than twice they may correct me.

The probem I have with using people used to racing is they practice their braking from high speed. And I agree, from high speed (especially 200km/h +) I think use of the rear brake is pointless.

However braking from road speed in an emergency stop is different because it takes longer for the weight to shift onto the front tyre.

Crasherfromwayback

9th March 2010, 13:04

The probem I have with using people used to racing is they practice their braking from high speed. And I agree, from high speed (especially 200km/h +) I think use of the rear brake is pointless.

However braking from road speed in an emergency stop is different because it takes longer for the weight to shift onto the front tyre.

An emergency stop is the same on track as it is on the road...and the weight transfer is all dependant on hard hard and quickly you apply pressure to the lever.

Coldrider

9th March 2010, 14:57

In KBland most do high speed.

p.dath

9th March 2010, 15:16

An emergency stop is the same on track as it is on the road...and the weight transfer is all dependant on hard hard and quickly you apply pressure to the lever.

I've given some further consideration to this one. I don't have track experience, so I have to do a lot of guessing (perhaps scracha could help fill in the blanks?).

I'm guessing that due to the higher speed, that if you start braking on the front tyre, then the front of the bike wants to start going slower than the back, and as a result the front suspension will load up at the speed difference between the front of the bike and the rear of the bike. Since velocity is directly related to time and distance (v=d/t), and the distance between the front and rear tyre remain constant, that the time for the weight to transfer must reduce as the velocity increases.

And similarly, at lower speed, say 50km/h, the speed difference between the front and rear of the bike would be less, which would mean it would take longer for the front of the bike to load up.

So the effectiveness of the rear brake varies with the speed you start the manoeuvre at. The faster your going, the less effective it will be.

If you consider a braking force so hard that the rear tyre is off the ground then you would have to agree that the rear brake, and engine braking, would have zero impact.
If you take the more likely case where the rear wheel is on the ground, but do acknowledge that most of the weight is on the front tyre, and very little on the rear tyre, then for the same reason above you must surely agree that braking and changing down would have little impact.

p.dath

9th March 2010, 15:18

ps. I have emailed the DSA asking when they teach to use the front brake first, then the rear brake, and if it was the result of a study or some research, and where I might be able to get that research from.

I suspect it may have come from an "expert panel".

Coldrider

9th March 2010, 18:26

I do stoppies in the carpark.
You should see a VFR800 under max front brakes, even the smoke does not know which way to go.

george formby

9th March 2010, 18:54

hayd3n

9th March 2010, 19:11

brian bernard taught them
from 100 kph to stop
my m8 in his old daytona 675 was down to about 30-35 metres
front only
grab and hand full of the front lever release and grab a big handfull again clutch or not
it slowed me from 100 to about 60 with a passenger in like 10 metres such a shame there was a couple of car on nboth sides of the road and only a bank on the other

BMWST?

9th March 2010, 19:25

Mmmm...it sure feels like it does to me. Got any links regarding this at all? Might be interesting to compare stoppping distances with and without change-downs. Must try it one day...

if you are really on the brakes the back wheel is almost in the air.

BMWST?

9th March 2010, 19:31

if the rear brake is applied first it begins the weight transfer the the front The rear brake will not be used anyharder than this initial application and in fact may have to be released entirely because the backwheel may be only intermittently on the ground.in theory at this point you can pull in the clutch cos there is no real braking from the rear wheel anyway.Now snick down through the gears so you you are in first when you stop.You are then in a position to ride away immediately when you see the 4x4 coming behind you isnt going to stop.thats the theory,i have not managed to put it into practise yet,i need to use all my concious thought on the act of braking.practise practise practise.it may say your life one day

p.dath

9th March 2010, 19:49

Found this interesting comment:
http://www.webbikeworld.com/Motorcycle-Safety/braking-tips.htm

The American Motorcycle Safety Foundation teaches their instructors that "in an emergency braking situation you should apply the back brake hard and let the back wheel slide if it wants to. This way you can concentrate on what is happening up front; there's enough to think about in the use of the front brake."

centaurus

9th March 2010, 20:00

The American Motorcycle Safety Foundation teaches their instructors that "in an emergency braking situation you should apply the back brake hard and let the back wheel slide if it wants to. This way you can concentrate on what is happening up front; there's enough to think about in the use of the front brake."

I'm sorry but this is the most stupid advice I've ever heard. And the bad news is that there are quite a few people preaching this thing (I've heard it before). What happens if the road has serious camber or you're downhill or on any other 1000 situations that will make your bike drop like a sack of potatoes if the back starts sliding? They somehow imagine that when you do emergency braking it will be on a straight road with no corners, no camber and no uphills/downhills. That's the only situation in which you can just ignore a sliding rear wheel. I've seen it a couple of times and experienced it once, a week after I bought my first bike. The result was a catastrophic fail: low side (on the uphill of the camber), then bounced in a strange highside that spun the bike 180deg so I ended up sliding backwards on my ass and watching the bike coming towards me. My only luck was that this was happening at low speeds so I didn't do any real damage to miself.

p.dath

9th March 2010, 20:04

I'm sorry but this is the most stupid advice I've ever heard. And the bad news is that there are quite a few people preaching this thing (I've heard it before). What happens if the road has serious camber or you're downhill or on any other 1000 situations that will make your bike drop like a sack of potatoes if the back starts sliding?

I wonder if this is a reflection in the variation in roading between countries. Perhaps maybe more riders are urban based where the roads tend to be flat and camber free in the USA? Don't know. Just taking a guess.

Coldrider

9th March 2010, 20:05

Found this interesting comment:
http://www.webbikeworld.com/Motorcycle-Safety/braking-tips.htmThe article assumes the rear wheel gets light but makes no mention of getting it airborne, which is another level again.
That article in NZised, Allan Kirk

dipshit

9th March 2010, 21:22

I've seen it a couple of times and experienced it once, a week after I bought my first bike.

:yawn:

Oh brother....

dipshit

9th March 2010, 21:34

my m8 in his old daytona 675 was down to about 30-35 metres
front only

It's interesting to note that in a British bike mag test, a 675 was absolutely cleaned up by big heavy bikes with linked front to rear ABS systems in a braking test.

Jonathan

9th March 2010, 22:28

Hahahaaaa!!! After reading this thread, next time I have to emergency break, this will be going through my brain - "hmm back break firs... no front brea... clutch in... or out? gear dow..."

THUD!!!

centaurus

9th March 2010, 22:39

Hahahaaaa!!! After reading this thread, next time I have to emergency break, this will be going through my brain - "hmm back break firs... no front brea... clutch in... or out? gear dow..."

THUD!!!

Why brake at all? If you go out might as well go out in style. Nobody cares about a biker who made a small dent in a car and scratched his fairings. However, if you manage to split the car in two... You might be dead but you will be a famous dead :D

Jonathan

9th March 2010, 23:04

However, if you manage to split the car in two... You might be dead but you will be a famous dead :D

Unfortunately it is much more likely I would end up squished on the front of a logging truck where I would remain unnoticed or passed off as some macabre hood ornament.

jonbuoy

9th March 2010, 23:19

p.dath

10th March 2010, 08:23

It's interesting to note that in a British bike mag test, a 675 was absolutely cleaned up by big heavy bikes with linked front to rear ABS systems in a braking test.

You might find that the extra weight on the wheels also helped. ABS with linked brakes should be the ultimate. Just squeeze on the front brake with maximum force and let the electronics figure it out.

Coldrider

10th March 2010, 08:30

Well executed emergency brake performed, what does the car behind do? (scenario).

centaurus

10th March 2010, 09:07

Well executed emergency brake performed, what does the car behind do? (scenario).

It is true that you need to be able to get out quickly after an emergency braking, howerver, if your emergency braking wasn't good enough it's not gonna matter that you were ready to get outta dodge. Let's put things in the proper order. First you need to have a GOOD emergency braking, and only AFTER the braking has worked you worry about getting out of there.

Even if you're in 6th gear, if your emergency braking has worked it only takes a second to drop down to 2 or 3rd and get out (most bikes have enough grunt to move from a standstill on 2nd or 3rd, some could do this even in 6th). If you fucked up the emergency braking and lying on the ground or smashed in the car in front, it's not gonna make any difference that you are already in 1st gear and ready to roll.

george formby

10th March 2010, 10:06

If your going for the rear brake without the front in an emergency braking situation its going to end in a world of trouble. Assuming your not talking about heavy braking on an approach to a corner? Emergency braking is when stopping is the only way to avoid whats just jumped out at you, does it really matter that afterwards you have to fiddle around trying to find first gear? The point is you stopped before hitting something.

I have had to emergency brake on more than one occasion to safely swerve not stop. Sitting at 100k on the open road at night to suddenly see a black dog lying on the road in front of me, oncoming traffic dazzling me & vehicles behind. If I had not change down as I braked, the bike would have stalled on me as I swerved & no doubt I would have been squished.

thehovel

10th March 2010, 17:41

Being a noob I've been practising emergency stops on some back roads near my house. This type of stop obviously dispenses with engine breaking and down shifting, so when I come to a stop I'm in 4th gear with the clutch in. Now when I try to shift down into first to pull away again, the gear selector lights just go blank, and the leaver feels like it's not shifting properly, like it's stuck in limbo somewhere around gear 3-and-a-half.

Sometimes, after struggling with the shifter for a while, it suddenly seems to find the gears again. Other times I've stopped the engine and restarted, or pulled away in 2nd because it won't go all the way down to first. It's a 2006 Suzuki GN250. Any words of wisdom?

(PS I already tried pulling away in 4th :D guess I wasn't pushing it fast enough).

Back to square 1 the question is about a newbie on a GN250 (not a sport bike on a track with linked brakes and ABS) All braking should be the same :throttle off (you don't want any more go fast); front brake on gently to start then harder ( to hard to start will just lock up the wheel.Then weight transfer happens : cluch in (by this time engine braking is gone): back brake gently to start then harder (see front brake): tap dance on the gear lever. The back wheel will become light but it will still be ON THE GROUND so it has braking ability. I have never seen anyone do a stoppy on a GN . Emergency braking is all of the above JUST QUICKER. Regards Richard

centaurus

10th March 2010, 19:09

Back to square 1 the question is about a newbie on a GN250 (not a sport bike on a track with linked brakes and ABS) All braking should be the same :throttle off (you don't want any more go fast); front brake on gently to start then harder ( to hard to start will just lock up the wheel.Then weight transfer happens : cluch in (by this time engine braking is gone): back brake gently to start then harder (see front brake): tap dance on the gear lever. The back wheel will become light but it will still be ON THE GROUND so it has braking ability. I have never seen anyone do a stoppy on a GN . Emergency braking is all of the above JUST QUICKER. Regards Richard

Haven't you read the rest of the thread? We have already established that rear brake can be initially applied hard if you want, but as you progress with the front brake the rear needs to be reduced due to loss of grip on the rear wheel while braking hard - or at least kept at the same level; in now way pressed harder.

If the engine is in gear, even "slamming" the rear brake while the front is not applied yet would not lock the wheel. That is another reason I keep the clutch engaged until the last moment - even if I end up pressing the rear brake too much, the engine will prevent locking in 99% or the cases.

i have seen stoppies on a GN250, 100% stock. Before we started the practical part, the BHS instructor showed us what the bike can do, trying to prove that a good rider can do many things even with a rubbish bike - wheelies, stoppies, scraping pegs on very low speed corners, etc...

george formby

10th March 2010, 19:20

If the engine is in gear, even "slamming" the rear brake while the front is not applied yet would not lock the wheel. That is another reason I keep the clutch engaged until the last moment - even if I end up pressing the rear brake too much, the engine will prevent locking in 99% or the cases.

Drivel

i have seen stoppies on a GN250, 100% stock. Before we started the practical part, the BHS instructor showed us what the bike can do, trying to prove that a good rider can do many things even with a rubbish bike - wheelies, stoppies, scraping pegs on very low speed corners, etc...
I believe. If a GL1800 can wheelie, a GN can stoppie

jonbuoy

10th March 2010, 19:20

I have had to emergency brake on more than one occasion to safely swerve not stop. Sitting at 100k on the open road at night to suddenly see a black dog lying on the road in front of me, oncoming traffic dazzling me & vehicles behind. If I had not change down as I braked, the bike would have stalled on me as I swerved & no doubt I would have been squished.

Thats why I said IF its the only way to avoid an accident, if you can steer around it great sometimes you won´t even get that option and it´ll be a panic for your brain to do something if your reflex is to hit the rear brake first thats not a good thing in my opinion. If the choice is slamming into the side of a car thats just pulled out, hitting oncoming traffic or coming to an embarrassing stop in gear and having a little wobble and stalling its still better than the other two options.

george formby

10th March 2010, 19:36

Thats why I said IF its the only way to avoid an accident, if you can steer around it great sometimes you won´t even get that option and it´ll be a panic for your brain to do something if your reflex is to hit the rear brake first thats not a good thing in my opinion. If the choice is slamming into the side of a car thats just pulled out, hitting oncoming traffic or coming to an embarrassing stop in gear and having a little wobble and stalling its still better than the other two options.

I agree with your opinion. Any save is a good save

robertvi

10th March 2010, 19:48

Thanks everyone for your advice! For the record, I did a beginner's riding skills course today (definitely worthwhile), and the drill was throttle off, clutch in, onto front brake smoothly, progressively harder and apply back brake lightly at the same time, work down the gears if you can manage.

Today I also used the trick of slightly releasing the clutch to get the gears to click-in when down shifting while stopped - thanks for the tip, this will save me a lot of bother practising emergency stops where I don't manage to down shift before I stop!

thehovel

11th March 2010, 18:35

Haven't you read the rest of the thread? We have already established that rear brake can be initially applied hard if you want, but as you progress with the front brake the rear needs to be reduced due to loss of grip on the rear wheel while braking hard - or at least kept at the same level; in now way pressed harder.

If the engine is in gear, even "slamming" the rear brake while the front is not applied yet would not lock the wheel. That is another reason I keep the clutch engaged until the last moment - even if I end up pressing the rear brake too much, the engine will prevent locking in 99% or the cases.

i have seen stoppies on a GN250, 100% stock. Before we started the practical part, the BHS instructor showed us what the bike can do, trying to prove that a good rider can do many things even with a rubbish bike - wheelies, stoppies, scraping pegs on very low speed corners, etc...

Ride in front of me

Metastable

13th March 2010, 18:36

Lots of conjecture & speculation about braking but I believe the essence is control. The front is the most effective, the rear is a variable & the topic of this thread, gear changing is the final point of maintaining control. If you cannot ride away from an emergency stop in a prompt & controlled manner during the proficiency test, you fail. Well, back in the day that was the case. Front, rear & engine breaking have vastly different effects on different types of bike's, roads, tyres, cambers, linked brakes, BMW's etc.
Somebody has already said, that being able to get out the way after braking may be the biggest safety benefit.

I was wondering if someone was going to mention being in the right gear.

In a true emergency braking situation, with a sportbike or similar, you are better off doing a quick stab of the rear as you are starting to load the front.... this is basically happening at the same time. You grab a handful of clutch lever and you start knocking down the gears (or up if GP shift). THERE IS NO TIME TO ENGINE BRAKE! You need to be in the right gear too take off and not get nailed from behind. You will have more than enough to process, that you shouldn't be trying to blip through gears.... that's just mental overload. Keep it simple.

At the track, hopefully you don't have to emergency brake.... but you don't use much engine braking there either on a lap by lap basis. Brakes are for braking, the engine is there to make you go fast. You are either on the gas or on the brakes with very little coasting.... well if you're really fast you are... I'm not, so I catch myself coasting. :D

Note to the OP and newbies.... good on you for practicing emergency braking. If you go X speed, you should practice emergency braking from that speed, so that you know what it will be like.... otherwise how are you suppose to learn?

Also - on a bike like a cruiser, the amount of rear brake use is much more significant. I can understand that American MSF suggestion. On a cruiser (the majority of bikes there are cruisers) you want to keep that rear brake on hard as well as the front, but there is much less weight transfer.... if you use the front only, you'll take a lot longer to stop. It was interesting seeing the California Highway Patrol doing emergency braking... when they used both they stopped a bit quicker (BMW RTs I think)... rear only took forever to stop... front only was pretty good, but not as good as both. There was another one I saw with a cruiser and a Fireblade..... roughly the same distance for both... that was impressive. More rear brake usage on the cruiser obviously.

One last tidbit, be careful in a parking lot. It can sometimes be a bit dusty. If you are practicing emergency braking, the front wheel might lock on you. BUT.... that's actually a good skill to learn too, how to quickly release the front brake if the front locks, so that it doesn't tuck. There is plenty of time, but you have to again, know what to expect, otherwise you won't release the front brake quickly enough.

CookMySock

13th March 2010, 21:22

If you want some damn good emergency stopping practice, try a track day. Every corner is an emergency stop!

:niceone:

Steve

scracha

14th March 2010, 18:44

If you want some damn good emergency stopping practice, try a track day. Every corner is an emergency stop!

Steve
Absolute pure pish.

Unless a superdooperfragilisticmotord sticks it in front of you mid-corner.

SMOKEU

14th March 2010, 18:57

Anything that is going to slow you down faster has got to be good.

Including crashing into the back of a truck?

dragon_fly

18th March 2010, 19:45

centaurus

18th March 2010, 20:06

holy crap you guys are confusing
emergency breaking is part of my new practising too....
i put my clutch in at the moment and even though as a woman i am a master at multi tasking.... cough cough...... i would be struggling to change down quickly.... clutching in and out (or do you do it with the clutch out and just slam it down??) as well as trying to feel if im starting to lock up.... lol as well as analysing how far it is taking me to stop......... major brain strain......

I'm not gonna reiterate the change gear/don't change gear during emergency braking, but If you really want to change down, you don't release the clutch. Pull the clutch in and while the bike is slowing down keep changing down. Just make sure that when you engage the clutch again you are stopped (or almost stopped) and in first gear. You don't want to lock up the rear wheel by being in the wrong gear and while you are braking for your life you can't be expected to keep track of what gear you're in vs. your speed.