How to avoid going too quickly into a bend…
One of the more difficult lessons to learn is getting the right speed for bends, not least because these are done quite differently to how people generally take them while driving a car. Cars weigh a lot, which makes a virtue out of not slowing down and where possible carrying speed; compared to a motorcycle they are relatively slow at accelerating. However, cars have far less problem with both braking and turning, and poor road surfaces; things that cause significant issues for motorcyclists. Typically, most car drivers will begin braking as they turn into the corner, continue to brake to the apex and then accelerate from there. This is not ideal, but modern cars and tyres deal with this reasonably well.
Physics plays a major role in how this works for a motorcycle, and one of the biggest concerns is the wheelbase. The wheelbase of a car does not change as the suspension is up and down, whereas for a motorcycle the wheelbase changes every time it accelerates or brakes. This is because the front forks are at an angle (what’s called the rake). This means that the wheelbase is shorter during braking and longer during accelerating. This matters because the wheelbase has a very significant impact on how quickly a vehicle will turn. A longer motorcycle will be more stable but turn slowly (e.g. a Harley Davidson Sportster) and a shorter one (e.g. a Yamaha R6) will be nimbler. Clearly, altering the wheelbase in the middle of a bend will have an impact on how the motorcycle steers.
The next issue is braking; and this has two impacts. Firstly, braking with the front brake has the effect of making the motorcycle sit up (i.e. stop leaning). Secondly, braking and turning places lateral loads on the front tyre and can cause it to slip sideways, and this is not something that ABS can prevent from happening. ABS deals principally with the under rotation of the wheel, in other words if the wheel starts to stop turning (because the brake is locking) then it releases the brake. What motorcycles do well is braking in a straight line; this means bends should be approached slower than perhaps you are used to in a car. The braking should finish before you start leaning into the bend, which should be entered on ideally a gently rising throttle (giving you a long wheelbase). In the event the bend tightens, or you need to slow, then closing the throttle and using the rear brake will both slow the motorcycle and shorten the wheelbase (making the bike turn quicker).
How fast can you go around a bend? The speed in bends is limited by several factors (other than the speed limit): the road surface, how far you can see safely to stop, your confidence and ultimately the performance of your motorcycle.
The road surface is a straight forward issue. Motorcycles perform very well on dry clean tarmac, and reasonably well on wet clean tarmac. However, anything on the tarmac that is either loose or slippery is very difficult to deal with; e.g. spilt fuel, wet leaves, gravel and mud. Fortunately, these occur in places and times that are predictable. Fuel is often spilt near petrol stations (for example a roundabout). Wet leaves occur under trees, after rain or high winds, often in autumn. Gravel occurs after heavy down pours or after long dry spells. And mud – well what about that open gate or new housing development? Think about your environment and consider the hazards.
How far you can see safely to stop is critical. Essentially, you should not ride faster than you can see safely to stop, for good reason – motorcycles are very poor at braking and turning. Anything that is moving slowly (horses, pedestrians) or is stationary (tractors, hedge cutters, or a broken-down vehicle) are serious considerations. The point at which you can no longer see past is referred to as the “vanishing point” – where both curbs or hedgerows appear to meet. Using the vanishing point is very helpful in getting the correct speed for a bend. If the vanishing point on the approach to a bend is staying where it is then the bend is sharp, and you need to slow. As soon as the vanishing point is moving and staying at a distance that you can see safely to stop then you are riding at an appropriate speed. Once the vanishing point starts to pull away from you as the bend develops this is your cue to start increasing your speed. With more advanced training you will be taught to move your position on the approach to a bend to maximise the view allowing you to travel faster (for example moving towards the centre white lines as you approach a left-hand bend). Assessing and understanding the vanishing point is a skill learnt with practice.
Your confidence is a much more subjective issue. However, a good rule of thumb is “less is more” – start well inside your confidence levels. Very few people will fall off a motorcycle by going too slowly through a bend, whereas the accidents statistics are full of those that tried to ride too fast. Track days are a very good place to learn to improve your confidence; the environment is safe, and instructors are often on hand. Alternatively, a bend that has a clear view to the other side (i.e. where there are no fences, walls or hedge rows) also helps gain confidence. Confidence is often hard won and easily lost – don’t blow it by trying to keep up with friends and thereby giving yourself a scare. Building confidence should be done in steady steps with lots of practice.
Different motorcycles have vast ranges of performance parameters – from very little ground clearance on some custom motorcycles to huge amounts on sports bikes. The same can be said for tyres; a sports tyre will have much more grip than an off-road tyre. Suspension also plays its part in how well your motorcycle will cope with a bend. Rather like learning confidence, moving towards the limits of your motorcycle’s performance needs to be taken in modest and considered steps. Finding the limit is not a goal, but being aware of it will help you ride safely.
Finally, if you do drive a car consider adapting your driving to match the style in which you’d like to ride a motorcycle – assess the vanishing point, brake in a straight line, gently accelerate into the bend and don’t go faster than you can see to stop.