Part Two


Predicting Traffic Behaviour

Wouldn’t it be cool if you knew what every vehicle on the road was going to do before they did it? The truth is that experienced riders can actually predict traffic behaviour – it’s is not a black art, it’s just a question of knowing which signs to look for.

The reason why it is important to be able to predict with reasonable accuracy what drivers are going to do, is because when commuting in traffic you often have very little space to manoeuvre should something go wrong. This is especially important when you’re lane-splitting, where you are sometimes separated from other traffic by mere centimetres. With your reaction space so severely restricted, you lose most of your options in an emergency situation – you can’t swerve, your escape routes are cut off, and you’re most likely limited to braking as the only form of evasive action. Personally, I hate to have only one option in an emergency situation; therefore, I work from the premise that prevention is better than cure – in other words, I try stop the problem from becoming a problem in the first place, rather than wait for it to happen and then react to it.

More often than not, drivers give tell-tale signs of what they intend to do. The most obvious one is a car with an indicator going blinkety-blink – it doesn’t take a rocket scientist to figure out that the car is going to make a turn or change lane at some point (although, in some cases, it simply means the driver knows how to operate the indicator stalk, and nothing beyond that). But there are other less obvious signs that can also help you predict behaviour, especially when you’re lane-splitting in heavy traffic. Cars will often edge slowly towards the adjacent lane before they change lanes. If you are approaching a car that’s doing this, assume that he is going to change lanes and slow down to accommodate him. Never accelerate to prevent a lane change – quite often the driver will be blissfully unaware of your presence, and you could end up being cut off at a speed too high to allow you to evade in time.

Be on the lookout for cars that accelerate or brake suddenly (especially if there are no obstacles in front of them) – they might do it to take a (real or imagined) gap in the next lane (see image above). Sudden checking of mirrors is another indicator of an imminent lane change. Most drivers tend to (rightly) focus more on the road ahead than on their mirrors, so a person who suddenly begins to look around is probably planning a lane change. Again, rather assume it and be mistaken than ignore it and be in pain. If you’re lane-splitting and there’s a gap in one of the lanes, expect somebody to want to fill it. If there’s a gap of several car lengths ahead of you, expect one or more of the cars in the adjacent lane to cut into your lane. Often such a gap will be an opportunity for you to speed up reasonably safely, so be vigilant and prepared to take sudden evasive measures (see image below).

As you probably know, minibus taxis are true ‘lane-surfers’ – they will merrily jump from lane to lane in an attempt to get through traffic quickly. There is only one rule when approaching a taxi: expect the unexpected. Your only defence is to make sure the taxi driver is aware of you and be prepared to counter an unexpected swerve immediately. I normally don’t pass a minibus taxi if there is a gap in the traffic next to him (and even so, I’ve seen minibuses attempting lane changes with cheerful disregard to the fact that there is no space in the next lane).

A good trick is to try to notice each car individually as you drive through the stream of traffic, ascertaining whether their indicators are on or off, considering their positions in the lane, and looking at the head movements of the drivers – don’t worry about a mental overload: your brain is a remarkable computer, and you’ll be surprised at how much information in can process.It goes without saying that you can’t do this effectively when you’re going too fast; if it’s too difficult, it’s a good indication that you should consider slowing down. The key is not just to predict drivers’ behaviour, but to be constantly prepared to deal with their moves. More often than not, your best defence is to drop back, let the offending driver do whatever he wants to, and pass him when it’s safe to do so.

I can’t over-emphasise the importance of defensive driving on a bike, especially in traffic. Always remember that you are a lot less protected than people in a car, and precariously balanced at best. In an argument between a car and a bike, guess who’s going to come off second best? Get to your destination alive – all other considerations are secondary to that.



© Dries van der Walt, 2008. Click on 'About' to see copyright information.