Safe Speed Forums

I thought you'd gone away to leave me in peace

OK - Front brake is, say, 80% more efficient than the rear. Rear brake becomes less and less effective as the bike dives, to the point where it will lock up and the wheel will skid. Once this point is reached, it's about useless.
Many 'hardened' bikers will never touch the rear brake for this very reason.

I would agree that if we are in 'bottom clenching' mode - forget about rear brake and concentrate on managing the front to avoid skidding.

Personally, I think this approach is wrong for 'normal' heavy braking when balancing both brakes will improve the braking efficiency and 'stabilise' the bike.

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It's tricky doing nothing - you never know when you're finished

Well, I am away but I'm still here. I'm presently pleasantly parked in a Buckinghamshire layby.

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Paul Smith
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The Safe Speed campaign demands a return to intelligent road safety

Given the differing braking capabilities of motorcycles they are not all capable of easily lifting the back wheel under braking. If they were we'd have a lot of youngsters going over the handle bars I would suggest.

I would say that in the case of my bike for example (the Deauville) I would have to take extreme measures to get the wheel to lift more than momentarily including deliberately shifting my weight forward.

Also, if we are getting into details, in the case of the Deauville in order to achieve 100% braking on the front wheel you would have to utilise the rear brake pedal to engage the 6th piston in the linked brakes.

If its an emergency braking situation I'm inclined to give it everything I've got rather than worry how much the rear wheel is contributing, if it is contributing then that's what I want. If it's in the air it doesn't really matter if it's free-wheeling or locked. It will matter when it touches down again though as it will contribute to stopping the bike once more.

This may be different on the latest superbikes which have more powerful brakes and less weight over the rear wheels, I don't know, I've not braked hard on them like I have on my bike.

To add to this.

I am currently reading this: http://www.fmq.qc.ca/pdf/amorce-freinage_eng.pdf

Which deals with "Task analysis for intensive braking of a motorcycle in a straight line"

How to do stoppies:
Slam the front on HARD then ease of as the back comes up

How to do wheelies
Rev to 'lots' then dump the clutch and relax the throttle as the wheel comes up (cover back brake just in case......)

How to stop like the bloody clappers without doing a stoppie:
Gentle brake, wait for the front suspension to lock itself out then as much force as you dare

How to pull away like the clappers lots:
Rev to lots, ease the clutch out then as the back bites give it handfuls.

Its about lining the mass acting with the right point. For example on braking getting the suspension compressed has the mass acting through a line far close and pointing towards the ground.A stoppie has the mass high up acting parallel to the ground.

It is possible to wheelie a deauville to whoever posted they had one Stoppies on the other hand you will have to try for yourself!

BTW with a light rear wheel you risk lock up and then a release risks a high side if the wheel has skipped out of line. If you are not good and quick with the clutch a stalled engine. Better just leave the rear slowing and turning under engine breaking.

Again this tends to be on sports bikes/sports tourers.

'twas me. Its only 3 months old, I'm not prepared to abuse it or risk dropping it to find out to be honest. I need to ride it to work every day.

We seem to be drifting further from the original topic (perhaps some of this could be split into a thread in the motorcycling section?) but it has got me interested now.

I found this analysis of braking with/without ABS and Linked brakes.

http://www.msf-usa.org/imsc/proceedings ... stance.pdf

The conclusion seems to be that if you have ABS then you stop in the shortest distance by using both brakes (but must keep the rear wheel on the ground) but without ABS using the front only is shortest.

They do appear to have skewed the figures slightly though by taking the average for the ABS tests and the best figure from the non-ABS tests which doesn't seem particularly 'fair'.

The most marked difference was two-up on a BMW R1150R at 48km/h in the wet where ABS stops you 12ft sooner than without ABS.

Well the brakes have not been applied to this thread. It's shot off since I last looked. Amazing how one comment can cause a thread to swerve violently

Some of you may have read about my "stoppie" experience but for those that haven't. I was on a fast road and braking to adjust my speed approaching a roundabout which had a car on my junction waiting to pull out. I checked the car and saw the brake lights go out so thought he was pulling out. Checked the traffic on the roundabout and as it was clear started to ease off the brake. As I looked to the corner exiting the junction I saw that the car hadn't moved one jot so slammed the front brake on. The forks did compress to their limit and I realised that I was still in danger of hitting the back of the car to applied more front brake. That was when the bike went into a stoppie, continued, deposited me on the road about 10 ft from the back of the car then fell on top of me.

What did I learn from this; apart from being a damn sight more observant of the cars and my positioning in the lane approaching a roundabout?

Trying to do an emergency stop without a rear brake is foolish in the extreme as it can lead to a handlebar flip. I am sure that the gyroscopic inertia inherent in a freewheeling rear wheel provides enough force to exaggerate the lifting of the back of the bike.

I have since had to perform other emergency stops (T-junctions ) and have applied some rear brake in those situations and found the stop to be more controllable. However, instead of a straight line deceleration, on my bike at least, the rear tends to drift slightly to the right so that I end up looking like Nicky Hayden approaching a corner As I am aware that this is going to happen I can now anticipate and control the bike better.

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Prepare to be Judged

WOW

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It's tricky doing nothing - you never know when you're finished