How to brake quickly and safely

[idontknow]

I was reading another forum and found this http://www.msgroup.org/forums/mtt/to...?TOPIC_ID=3709 which relates well

[sinned]

I was reading another forum and found this http://www.msgroup.org/forums/mtt/to...?TOPIC_ID=3709 which relates well

I am not sure what value this adds but has given a few with mathematical skills superior to mine the opportunity of displaying how smart they are. I think the key benefit from sucking the clutch in is that the motor will not stall (ie will keep running) and if in the less than 3 secs from a howling stop from 80 - 120k you can tap the gears down to first you will have engine running and gear to escape in. Escape??? - that will be after your nuts have emerged and eyes stopped watering.

[The Stranger:Me]

I am not sure what value this adds but has given a few with mathematical skills superior to mine the opportunity of displaying how smart they are. I think the key benefit from sucking the clutch in is that the motor will not stall (ie will keep running) and if in the less than 3 secs from a howling stop from 80 - 120k you can tap the gears down to first you will have engine running and gear to escape in. Escape??? - that will be after your nuts have emerged and eyes stopped watering.

Um, didn't they say the key benefit is that with the clutch in you are not trying to brake the engine as well, thus more braking to the wheels.

Found the study interesting for several reasons.
1) They state "We retained the services of eight experienced riders"
2) The bikes were "equipped with outriggers"
3) They did 820 tests of which 298 tests met the criteria.
4) Data collection on the bikes was via a "full-Size Macintosh G4/867 computer carried on board the motorcycle"

So if we look a little further at this.
1) Most bikes do not have outriggers thus can not afford to throw caution to the wind. The wheels of a bike are a gyroscope. Lock one wheel in a straight line and you still have a gyroscope to assist you to stay upright. Lock both and the odds of staying up decrease (as well as braking effectiveness decreasing). I can't quite reconcile getting on the rear first still. The rear of the GSXR is already skipping under heavy front braking, just touching the rear at all locks it, thus I loose both the anchor effect to help keep my path of travel straight and the gyroscopic benefit of the rear. Not saying, don't touch the rear. But personally I will still be getting the front working as best I can first so as the rear doesn't lock as it unloads.

2) Despite using eight "experienced" riders they discarded 522 of the 820 tests. What? Like there is an emergency, you go under the Mack truck, so you lift the truck off and go - oh hold on, that one didn't count, I want another shot.
Me wonders if the sequence is that difficult for experienced riders if it should not be amended to account for less experienced (normal) riders.

3) They had a full size Macintosh computer, in a protective enclosure sitting behind the rider. Now say 15kg for a computer - but see the size of the enclosure, possibly all up 40kg. Not only this it is rear of the rear axle, thus multiplying the weight to some degree. Of course the rear brake is going to show an effect. I am bloody sure that an extra 30-50kg of weight, securely fixed over my rear axle would allow me to get benefit from the rear brake too.

[Ixion]

Well, the statistical basis of that report seems very dubious, since they appear to have selected the results they wanted and discarded those which did not suit their theories.

The situation also does not relate to the real world.

If I had outriggers also, I would be less concerned about locking the rear wheel. However , in the real world, the issue of back wheel lock up is a real one. It's easy to do, and once locked you have to leave it locked, or risk a high side.

Which is why some riders say don't use the rear at all. But, the effect of the rear brake IS important in that first part second, before the front has time to start deceleration (the first part second of front brake just compresses the suspension). So not using it loses valuable braking effort.

Overall, the experiment offered is irrelevant to the real world. The riders in the experiment did not have to worry about losing control. In the real world , loss of control is the second most important thing the rider must be concerned with (the first, of couse, being not hitting the obstacle).

A locked rear wheel means loss of control. Lost control means, possibly a crash in its own right (high side if you release the wheel, low side if you leave it locked). More importantly, with the rear locked, you lose the ability to switch from braking to dodging if the opportunity arises (car pulls out in front of you, brake, then go round behind him, for instance).

So in the real world, you want to not lock the rear if possible. But that's quite hard . Leaving the clutch engaged helps avoid rear wheel lock up.

(If you do lock it, leave it locked. Better some fishtailing than a high side) .

I think we may take a lesson from the racing world. Racers are very interested in braking as hard as possible ,without losing control. I never heard of any racer who declutched while braking (except for gear changing, obviously). If declutching reduced braking times, I'm sure racers would do it.

[sinned]

There is a difference between race braking, fast or hard stop and a panic stop. A panic stop is unplanned and unexpected and to add to the stress when the anchors come on you may not know if you can stop in the distance to that car/truck/horse etc. If your normally stopping action is to use the rear brake then that is probably what you will do without thinking. I am practicing using just the front brake except I use the rear for low speed control and hopefully if I am ever in the panic situation I will not lock the rear as it will not be in my automatic reflex action to initially use it. It sounds great in theory to apply both brakes firmly and then ease of the rear as the back lightens and this probably works well on the track where the rider is focused on one thing and every action is planned. Different to cruising down the road observing the scenery and thinking of sex.

[The Stranger:Me]

If your normally stopping action is to use the rear brake then that is probably what you will do without thinking. I am practicing using just the front brake.

That really is a point which is not sometimes so obvious but is important to ALL riders new and old. Older riders tend to let bad habit creap back in, they become comfortable and complacent. You see this with the accident stats.

In an emergency you will rely upon instinct. If for example you cover the brake with 2 fingers, in an emargency you will use 2 fingers on the brake.

So when on a motorcycle, think motorcycle and focus on doing things correctly for a motorcycle at all times so as it become habitual.

[terbang]

1) was told by a friend of mine to imagine your "landing an aeroplane". Begin loading the back then just after load up the front, with your bike lowering onto suspension at an angle - hence the landing part!

Can't help myself but planes don't have front brakes...!

Concentrate on the front first.
Squeeze, wait for weight transfer then apply more pressure. You are aiming for a point just before lock up.

If you just grab and don't wait for the weight to transfer it is more likely to lock.

Next apply the rear.

On a sport bike it is often of no use using the rear because you will have so much weight on the front even a light touch will lock it up. If the clutch is out (as it should) you will have the benefit of engine braking on the rear.

If you apply rear first
1) You loose time on the most effective brake
2) As you do apply the front and the weight transfers the rear unloads and starts to skid, thus reducing it's effectiveness.

If you apply them at the same time, see 2 above.

So to summarise.
Front first.
Allow weight to transfer and get front working at it's most efficient.
Apply rear if you will get anything out of it.
Eyes up and ahead. After watching hundreds of emergency braking sessions you soon see, the ones who look down head that way.

Perfect in my view and I have often heard the initial "Squeeze" that CaN is talking about, referred to as a setup. It takes up the slack of the suspension and brakes and starts transferring the weight toward the front.

When riding on the road and if unsure of the outcome of the cage situation ahead that is perhaps looking a bit dodgey I will do a little setup as a precaution. The added advantage of this is that your brake light illuminates for anyone who is following behind giving a fair warning of a possible quick stop.

[ManDownUnder]

I can't quite reconcile getting on the rear first still. The rear of the GSXR is already skipping under heavy front braking, just touching the rear at all locks it, thus I loose both the anchor effect to help keep my path of travel straight and the gyroscopic benefit of the rear. Not saying, don't touch the rear. But personally I will still be getting the front working as best I can first so as the rear doesn't lock as it unloads.

My understanding is the rear brake loads up the rear shock(s) causing the bike to squat, lower the centre of gravity.

This in turn reduces the bikes inclination to lift the rear off the ground (i.e. stoppie).

That being said I don't practice (either rehearse or actually do) putting the rear brake on first. It goes on at the same time at the front under emergency stop conditions. I know that I throw enough weight on the front wheel to considerably (or totally) take the weight off the rear and it drifts left and right as it skids. It has locked up but provides bog all traction anyway so I figure it's no great loss.

The weight, braking and grip of the front tire does almost all the work when stopping as fast as I can, but how it gets to that point I can honestly say I haven't stopped to analyse (that I can recall anyway).

That's not to say what I'm doing is right. It is simply what I do after quite a while in the saddle and I can stop nearly as well as anyone I know.

I'm always open to pointers of course

[terbang]

Its a 'Horses for courses" thing really.
I once saw a magazine article that had comparison of stopping distances for various bikes and to my dismay it was the big heavy cruiser types that were doing well. The low CofG and length of cruisers tends to stop them pivoting up over the front axle (stoppie) which is the limiting factor on a sportsbike.
First thing my american mate said to me when fiitting me up on his spare harley was. 'Learn to use the back brake boy, its not like that sprot thing you have'. He was right it did stop well, though I still used the front first, I could also use the rear to much greater effect than on my own bike.