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Defensive Riding, Machine Control, Progress, Steering

Running wide in corners

One of the most common bend errors that riders make is running wide in corners. Although many times, we’ll get away with it, particularly if we run wide over the centre line and there’s nothing coming the other way, running wide has a high potential for serious accidents – it’s one of the major causes of bend fatalities, not just in the UK but world-wide.

Of course, the best solution is not to run wide in the first place, by using the “Vision” Line I’ve talked about elsewhere, so that you don’t turn into the corner until you can see the exit to the turn – that way it’s easy to aim across the second half of the bend and get the bike lined up right onto the following straight or into the next bend.

However, there are some contributory errors that are easy to avoid if we know what they are.

The first is to avoid gassing the throttle until the bike is pointed directly where we want to go next – turn at constant speed until the bike is upright THEN open the throttle.

The temptation is always to open the throttle and “power” through the turn – I’ve even seen advice that says this is a good way to corner because it “picks the bike up” – but in fact if we haven’t actually got the bike out of the bend, the increased speed will make the bike run wide unless we increase the lean angle to deal with the increased speed.

The other downsides are that it’ll also take longer to complete the turn than if we turn slower and squarer which actually delays the point we can get harder on the power – much easier if we are upright – and the extra thrust and lean angle we’re asking from the rear tyre increases the risk of spinning up the back wheel, which is how highsides are born.

I know (and have been told fairly frequently!) this technique of squaring turns off goes contrary to most riding advice where wide lines are seen as “increasing stability”, but if like most of us, you trade off the wider line for more speed then the stability issue is a non-starter – it’s only going to increase stability if you don’t go any faster!

Something else to consider is that this approach came from police practice in the 60s, when they were riding 50hp Triumph Saints and BMW R80s on narrow tyres, and needed to maintain all the momentum they could on pursuit duty.

We simply don’t need this “conservation of momentum” approach through bends as civvie riders. And nowadays anything 600cc and up is so powerful we’ve got more acceleration than we can possibly need, so even if every second’s progress possibly mattered, there’s no loss of time by using the slower, squarer turn approach.

One more consideration is that road surfaces have deteriorated, so it’s easy to lose traction by overwhelming the rear, particularly in wet and cold conditions, something not helped by the many riders choosing to fit sports rubber which doesn’t work outstandingly well in the wet.

A second approach we can look at to pull a bike that is in danger of running wide back on course is to use the counterweighting technique, where the rider leans OUT and pushes the bike DOWN. This works because the radius of the turn is controlled mostly by the lean angle of the TYRES, not the combined centre of mass of bike and rider – this has a small effect but nothing like the camber effect of the tyres.

If you don’t believe me, practice it in the carpark – it’s what we teach riders to do to get round the U turn on the bike test. By sitting upright and leaning the bike over, you can easily cut one metre of the radius of your turn – which could be all the difference between just making it round the bend inside the white line and becoming the bonnet ornament on an oncoming Scania!

Once again, this goes against most conventional advice not to push the bike down beneath us, because of several assumptions.

The first is that leaning the bike more increases the stress on the tyres. That’s wrong – it’s angular momentum which controls how much grip we need to make a turn, which is a combination of speed and the turn radius, and that is more or less independent of the lean angle of the tyres. There’s a small effect from moving the centre of mass but it’s only of interest to racers on the edges of adhesion.

Another objection is that keeping the bike upright puts the bike on the “fattest” bit of the tyre and thus gives us more grip. Actually, if you take a look at front tyres, they’re other perfectly rounded or triangular – thus either giving a consistant contact patch  from upright to full lean, or in fact putting MORE rubber on the road when the bike is leaned over. The fatter part idea refers to the rear tyre, not the front, and only becomes important when we’re winding the power on. Mid turn and leaning on a steady throttle, we’re looking for front tyre grip to keep steering round the bend, and the rear will just follow if the front sticks.

The third and more obvious one is the ground clearance issue, but at anything like normal road speeds it’s is not going to cause any ground clearance issues on most bikes – some sports bikes can hit getting on for 60 degrees of lean angle before anything touches down.

Tourers and particularly customs are more restricted, but quite frankly if the machine we’re riding has no ground clearance left we might ask ourselves if riding that hard on the road is wise in the first place!

The third approach is to use countersteering positively. If we’re running wide on any turn, and this includes slow turns emerging from or turning into side roads, we can be far more aggressive with the steering.

We’re extremely unlikely to make the front tyre “unstick” because the tyre has more than enough grip to cope with virtually anything we can throw at it on any normal surface – we can even steer on ice if we’re careful!

Once again, conventional wisdom suggests that being postive with the
steering “destabilises” the machine, but quite frankly, the front tyre and suspension are well up to it – steering just doesn’t generate the same forces as braking or accelerating do. I’ve found many inventive ways to fall of a motorcycle but have never unstuck the front from just steering – in fact through a “flip flop” chicane, I’ve steered so hard the front tyre came clear off the ground but as soon as it landed, it stuck again – you can see 125 racers doing this on the track sometimes.

So, in conclusion, if we are running wide in a bend there are places at the bar of the last chance saloon; we just have to recognise them and grab them whilst we can.

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About Kevin Williams / Survival Skills

Motorcycle trainer, motorcycle author, motorcycle safety consultant, motorcycle forum moderator, former courier and ever a recreational rider. Is there a common theme here?

Discussion

2 thoughts on “Running wide in corners

  1. If you’re referring to the discussion of ‘counterweighting’ as a means of tightening up a cornering line, the answer is no, it’s a body shifting technique, not a movement of the handlebars.

    If you’re already cornering, you’re already countersteering.

    So the technique I’m explaining is that if we combine counterweighting WITH countersteering, then we have an extremely powerful method of changing direction and tightening the line very rapidly indeed.

    Posted by Kevin Williams / Survival Skills | October 1, 2015, 9:34 am
  2. Is approach 2 effectively a countersteering measure in practice?

    Posted by Nikos World | October 1, 2015, 7:50 am
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