Emergency Braking

[NDORFN]

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

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]

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]

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]

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]

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???

[The Stranger:Me]

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]

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).

[Chrislost]

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).

nup.
im claiming that it FEELS HARDER to do said stoppie.

[MyGSXF:Me]

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!

[Devil]

... 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]

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]

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).

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]

So too sum up...

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

[mossy1200]

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]

The pillion had a woodie???

Hm. Perhaps I better rephrase that.