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What is the main danger in riding on bitumen after a rain shower? What is the main danger in riding on bitumen after a rain shower?

  • A. Glare from the sun

  • B. Manhole covers and road markings

  • C. Wet bitumen is very slippery

  • D. Other vehicles

    The correct answer is B
    Correct. However, there still may be significant glare from a shiny road surface, and wet bitumen is more slippery than dry bitumen.

Braking and avoiding objects while on a motorbike

The front brake assumes about 75-90% of the braking performance when you brake on a bike, depending on the style of bike. A sport bike will take more braking on the front wheel, whereas a cruiser carries more weight over the rear wheel and will have more braking power in the rear wheel. As you brake the weight shifts forwards over the front wheel. This lightens the load on the rear wheel and makes it more difficult for it to achieve any braking power.

Applying too much braking force causes the wheels to lock and skid. Once you are skidding you are not slowing down as quickly as you could. This is because the top layer of the tyre melts and acts more like a liquid.

Several reasons can cause you to be at more risk of skidding. Over-inflated tyres cause less tyre surface to be in contact with the road. Under-inflated tyres cause more tyre surface to contact the road (meaning more grip, but only to a point). A shaded corner in winter may still have frost or ice. Changing direction quickly could exceed the ability of the motorbike's grip levels.

In a skid, keeping both feet on the footrests and a lower centre of gravity will help you regain control.  You should also let off the brake until traction is regained, then reapply the brake.

Braking on slippery surfaces

If you are riding on a slippery surface, remember to use the brakes more gently. Riding on slippery surfaces is dangerous and you should minimise turning, braking and acceleration. Stay in a higher gear to avoid wheelspin and only brake when you are upright.

Staying upright gives you the best chance of stopping without the bike skidding from underneath you. Be prepared to put your feet out if that allows you to balance better. It will also prop you up if the bike does slip, but bear in mind you won't be able to use the rear brake if you take your foot off it. Applying the front brake first reduces the chance of a skid, and if at all possible, steering away from the hazard in the first place is preferable.

If you are riding after a rain shower, painted lines and metal manhole covers are extremely slippery when wet - far more so than wet bitumen. While the road will be more slippery than when it's dry, you should also be aware that there may be glare from the sun as well and this could obscure hazards on the road such as pedestrians, animals or potholes. 

Emergency braking

Upright is safest as the more your motorbike is leaning, the less grip you have. If your front wheel locks releasing the brake then reapplying it may prevent the front wheel from skidding out from underneath you. The rear wheel is more likely to lock because it has less weight over it.

When you are braking looking at where you want to go usually means you will steer automatically in that direction. Looking at the object you want to miss will often mean you will hit that object - it's called target fixation.

Emergency examples

Obstacle on the road: You are riding on a suburban street and a large piece of timber is immediately in front of you and there is no alternative but to ride over it. What should you do to keep control?

You should rise slightly in your seat, keep your balance neutral, straighten up the bike and hold onto the handgrips firmly to maintain control.

Animal on the road: If a dog rushes out in front of you, what should you do?

Slow down as much as possible, but don't avoid hitting it if there's no other option. You have a higher chance of surviving an impact with a small animal such as a dog than swerving into the path of an oncoming vehicle. If it's a much bigger animal, like a cow or deer, then you will need to make a split second judgement as to where you should steer.

Blowouts and punctures: If you get a blowout or puncture on your motorcycle, what should you do?

Avoid braking if possible. Close the throttle gradually and let the bike coast to a stop. Signal and move off to the side of the road. Keep your weight neutral if the rear wheel deflates; move your weight to the rear if the front wheel deflates.

Engine braking

If you don't use the brakes, and don't pull in the clutch, you will experience a small amount of engine braking when you release the throttle because of the inertia of the engine. The lower the gear you are in, the more engine braking you will experience because the lower gear will cause the engine to rev higher, thus providing more braking force.

Progressive braking

Progressive braking is when you apply enough braking force to start the transfer of weight to the front wheel, then progressively increase the force on the front brake to make full use of the front tyre gripping the road surface. Release brake pressure as you slow down to avoid locking the front wheel.

Stopping distance

The stopping distance is comprised of break reaction distance plus braking distance. At 50kph, your brake reaction distance is 14m - that's before you even apply the brakes.

This video explains motorcycle braking, showing you the differences in stopping distances using just the front brake, just the back brake, and both brakes together: