Emergency stop practice - gear change problem

[dipshit]

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]

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]

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]

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]

In KBland most do high speed.

[p.dath]

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]

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]

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]

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.

[hayd3n]

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?]

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?]

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]

Found this interesting comment:
http://www.webbikeworld.com/Motorcyc...aking-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]

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]

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.