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Compulsory ABS – good or bad?

If you’ve been keeping an eye on the latest news, you’ll probably be aware that the EU Commission is recommending mandatory ABS on all bikes over 125cc from 2017. ABS or linked brakes will be compulsory fitment on machines up to 125cc.

Is compulsory ABS a good thing?

I have to say I have mixed feelings about the issue.

Leaving aside:

– the political concerns about freedom of choice – the weight, cost and complexity (and consequent risk of failure!) considerations – the questions about whether ABS is appropriate for dual sport machines – the possibility of ‘risk compensation’ of riders coming to rely on ABS – the risk of ABS being seen as a ‘performance feature’ (it’s a bit worrying Honda have fitted the Fireblade with ABS before the learner and middleweight machines they sell to inexperienced riders) – the arguments about whether or not a skilled rider can out-brake ABS

… the important question is whether technological measures are the right answer to the right problem.

Firstly, there are arguments about how many accidents could be prevented by ABS. The pro-ABS case seems to be based on a Swedish study that suggests 48 per cent of all serious and fatal accidents could be prevented with the help of ABS.

On the other hand, ACEM say: “MAIDS and Hurt studies indicate that in 80 to 87% of PTW accidents, ABS has no effectiveness”.

So it doesn’t seem there is a clear argument for the effectiveness of the technological solution in the first place.

Secondly, let’s clarify what ABS (or linked brakes) can actually be expected to achieve; more rapid upright deceleration from a particular speed whilst maintaining a controlled stop.

Whilst in tests the benefit in terms of stopping distance of ABS-equipped bikes over conventional brakes are marginal or non-existant, ABS should take away the fear of hard braking. I’ve seen studies that suggest riders only use the front brake to something like 60% of its potential when braking in an emergency because of the fear of locking the wheel.

But there are two serious provisos here. First, ABS can only offer benefit if:

a) there is grip to be had b) there is sufficient distance to stop in

I’ve been in the passenger seat of an ABS-equipped car that buried itself in a hedge when the driver braked too late then discovered ABS doesn’t work on sheet ice. A rider making the same judgment error will be unable to stop, regardless of the fitment of ABS, linked or conventional brakes if he’s not left sufficient braking distance for the surface.

A third issue is the effectiveness of ABS when braking in bends – simply fitting ABS will not overcome the geometry changes which make braking and steering at the same time difficult – if anything, the ability to brake to the limit of adhesion might well make things worse.

So where might ABS be expected to help?

The obvious conclusion is that it could potentially help in urban areas, avoiding ‘SMIDSY’ accidents and hitting a slowing or stationary traffic ahead of the rider, by taking away the fear of hard braking and bringing the benefit to the rider of shorter braking distances.

But it’s important to put those “shorter distances” into perspective. Given that a rider can stop (in the dry) from 30mph in around five bike lengths, even using the brakes at less than full effectiveness won’t add more than a bike length or two to the stopping distance, and even if the rider does fail to stop, impact speeds would be relatively low.

The danger is not ‘not stopping’ so much as locking the front and falling off, and sliding with the rider’s speed over the ground barely checked.

We can say for sure (from accident studies) is that many of the riders who are involved in such collisions where ABS might be hoped to bring a bike to a controlled halt are inexperienced riders and riders in commuting situations, many of whom will be riding 50cc and 125cc machines with the bare minimum of training, often just CBT in the UK.

Nevertheless, these riders would have had emergency stop training on CBT. So why doesn’t our training prevent junction accidents?

The problem to my mind is partly in the way emergency stops are taught, and partly in the mindset of the rider.

Some years ago, I had a trainee out on her bike test when she crashed, locking the front brake when a car pulled out in front of her. The examiner commented that she had done a perfect emergency stop just a few seconds earlier and could easily have avoided the car. The conclusion has to be that there was nothing wrong with her braking technique per se, it was her situational awareness that let her down; the examiner raising his hand was not a surprise – but the car pulling out in front of her caught her cold and she panicked.

Unfortunately, many riders see this kind of accident as ‘unavoidable’. In fact, I came across this statement discussing this very issue of compulsory ABS:

“The people who need training are car drivers. Doesn’t matter how much safety you have on a motorcycle it wont stop them pulling out in front of you.”

Clearly, as long as riders believe that, they won’t take the important steps that help protect them at junctions, ABS notwithstanding;

– positioning themselves where they can see and be seen – expecting drivers to pull out so they aren’t caught by surprise – practicing their braking skills – most importantly of all, slowing down and reducing their momentum, and thus stopping distance – half your speed, reduce your stopping distance by THREE QUARTERS – in potentially hazardous situations like blind or busy junctions.

A proportion of fatal rural accidents happen at blind junctions, where the bike is carrying too much speed to stop. ABS won’t help here – it’s down to the rider to anticipate an emerging car and slow accordingly before reaching the junction.

My conclusions?

ABS is at best an “after the fact” aid. It should be clear that a more cautious approach to a hazard is far more effective than relying on ABS to stop you when the emergency DOES occur. ABS is not a solution to a lack of awareness and practical accident avoidance (rather than evasion) skills.

How will riders use it? As I said at the top, on the one hand there’s a potential risk of experienced riders using it as a performance aid or allowing good control and judgment to go rusty.

But on the other hand, riders don’t emerge on the road as ‘fully skilled’ no matter how carefully and thoroughly instructors teach them, so for riders who are climbing the learning curve first time round and who haven’t had the opportunity to hone their newly acquired skills in the first place, there could be a benefit in giving them chance to avoid the panic lock-up of the sort that caused my trainee to crash.

Treat ABS like day riding lights and hi-vis clothing. It might JUST help in an emergency. But it won’t prevent the emergency from happening.

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