Potholes are dangerous, but bumps or a seam of humps in the middle of a lane caused by heavy vehicles pushing the tar up can be much more dangerous to motorcycles.
Yet they are less likely to be fixed than potholes in yet another example of how the authorities ignore and neglect motorcycles.
A pothole can cause a big jolt in the front suspension, kick the handlebars about and possibly damage a rim. But at least the suspension is set up to absorb most of the impact.
When a motorcycle runs into a pothole, the suspension should be at its resting sag point and as the wheel drops into the hole, the suspension actually extends a little to absorb the hit.
Most of the damage is taken by the lip at the other side of the pothole, but by this time the suspension may be unloading again (depending on the length of the hole and your speed) and lifting the wheel up and over the lip.
It’s also usually over fairly quickly and you can be on your way.
Bumps more dangerous than potholes
However, bumps in the middle of a lane are far more dangerous.
They are usually a lateral series of bumps or a raised seam that goes on for a while causing a prolonged and detrimental affect on the suspension and steering.
They can lift the front wheel off the ground, kick the bike left or right into the bush or oncoming traffic, or cause a tank slapper where the handlebars oscillate wildly.
They are also much more difficult to see than a pothole which is usually darker and has broken asphalt. Of course, some potholes can also have debris, gravel and even rocks the size of footballs as this photo shows.
A hump may not have any unbroken asphalt and unless the sun is low, it won’t create a shadow so it’s less visible.
If you’re following traffic, you can watch the cars in front bumping around when they hit a pothole which alerts you to take avoiding action.
However, you won’t get the same alert of an impending mid-lane hump because most vehicles will straddle them.
If you are following a big vehicle like a truck, they can obscure a lot of the road ahead and you could suddenly find yourself confronted with a big hump emerging from under their vehicle.
And because most traffic is not upset by humps which they straddle, fewer complaints are made to the authorities, so councils are less inclined to fix them quickly as they might a pothole.
In fact, roadworkers can actually create these humps when they fix a series of outer wheel track potholes (the most common) with a half-lane patch, leaving a centre-lane seam or hump.
So what do we do about bumps and lumps in the road?
Here are five useful tips for coping with bumps:
On country roads where these humps are more likely to occur from heavy trucks on under-engineered roads, it’s best to ride in the wheel tracks, not in the middle of the lane.
Don’t follow cars and trucks too closely or you may get no notice of a looming bump.
If you see a bump, wash off as much speed as possible, but let the brakes go again before you hit the bump to ensure the suspension is not compressed or it won’t absorb the hit.
Move your upper body forward to keep weight on the front wheel so it doesn’t lift as far. At the same time move your elbows up and out while holding on firmly to the bars. This will help absorb some of the handlebar kick or tank slapper.