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Mark Hinchliffe·
Tips/trainingRiding/safety tips
··15 Comments·2 min read

Do motorcycle riders follow too closely?

Slow moving vehicle pull over turnout sign traffic follow
Broken lines on NZ winding road

A new study has found that one of the most common motorcycle crashes is riders running into the rear end of vehicles in front because they follow too closely.

The Virginia Tech Transportation Institute motorcycle crash study for Motorcycle Safety Foundation chose 100 volunteer riders to carry cameras so they could study their behaviour.

They recorded more than half a million kilometres of riding which included 30 crashes and 122 near-misses.

While the study is just the start of their real-world analysis, it did reveal the most common incident (35 crashes or near-misses) was riders crashing or just missing the rear end of the vehicle in front.

FOLLOW TOO CLOSELY?
Follow too closely tailgate

Riders often complain about being tailgated, but there is also a tendency for riders to follow vehicles closely. I confess to doing it myself.

The reason we follow closely is because a rider doesn’t have a bonnet/hood blocking their view of the road ahead.

Car drivers can’t see about 10m of road in front of them, so their visible road gap to the next vehicle is already 10m. If they then leave a gap of visible road, that is on top of the 10m.

Riders don’t have that 10m buffer. They see all of the road in front of their front tyre, so they tend to creep up closer to the vehicle in front, erroneously believing they are leaving a reasonable gap.

We also tend to want to overtake vehicles in front of us, so we follow closely to overtake quickly.

STOPPING DISTANCES

The problem is that a car with four large rubber contact patches on the bitumen will stop a lot faster than a motorcycle with two narrow tyres.

So if a vehicle stops suddenly, a rider has a lot less stopping distance before hitting the vehicle.

Also, it only takes a moment’s inattention and a stopped vehicle that is suddenly turning across the traffic looms up on us. Check this video.

We need to leave a three-second gap when we follow a vehicle. To gauge the gap, watch the rear of the vehicle in front pass a roadside object, then count to three and your bike should then be alongside that same object.

WEAVING TO AVOID A REAR-ENDER

Another cause of these rear-end incidents is that bikes cannot weave around a wide object, such as a vehicle in front, as quickly as a car can.

Yes, you may be able to steer or counter-steer your bike quickly, but after a quick flick of the bars, it tends to stand back up again.

Try it yourself. Steer or counter-steer the bike at any speed and see how far you go before the bike wants to stop steering and run straight again.

So if you are following a vehicle closely and it suddenly stops, you have less chance of avoiding the rear end of the vehicle. That’s especially true if you are riding in the middle of the lane like in the photo below.Follow too closely tailgate

You can increase your chances of weaving around the vehicle if you are riding in the left our right wheel track (depending on circumstances and whether it’s a left-drive or right-drive country).

In this position, you have less distance to weave and avoid the vehicle in front.

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Mark Hinchliffe
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15 Comments

  1. In the UK oriented MAIDS study, riders of 125cc and smaller bikes were vastly more likely to ride into the back of someone than any other group. At the time of the study a 125 could be ridden with minimal training and l plates, subsequent tests being taken on a 125 granting staged (33bhp for 2 years, then unrestricted) access. The first part of the test is an off road course that includes emergency stops and a swerve around an obsticle, both taken at 50 kph or more. Incidents of newly licensed riders rear-ending other vehicles appears much lower, although there is a confounding factor of almost all scooters here are 125cc, and the study postulates that some of the overrepresentstion may be down to the lack of engine braking on automatic transmissions.

  2. The person who has made statements about cars being able to stop and turn quicker than bikes is clearly not a rider and knows nothing of the dynamics of a bike. A motorbike can stop at upto 3Gs in the dry and provided there is no oil on the road a bike can still manage upto 2Gs in the wet and these numbers are prior to the advent of abs, and being a skilled filterer I have flicked a large bike from one side of a lane to another to avoid idiots trying to block me in the space of less than a car length. The issue is skill attention preparation and vehicle capabilities, the majority of people running into the back of vehicles will be predominantly novices scooter riders and cruiser riders and those who get over confident or distracted. When riding you need to remember that everyone is out to get you so you have to plan for the sudden stop, lane flick of the guy you’re beside or approaching being rearended or any number of things that often happen a hundred times in a twenty minute ride.

    1. Hi Al. I would love to know where your data is from? Most studies show cars decelerating at a max of 10m/s2 (1G) and motorcycles at 7.8m/s2 (0.78G). This is real world surface, bike and operator. You may want to read Vavryn, Winkelbauer, Austrian Road Safety Board, ‘Braking Performance of Experienced and Novice Motorcycle Riders – Results of a Field Study

      1. If Al is correct then I should be able to ride my bike down a vertical wall with plenty of G’s to spare.

        1. I just read that study and I’m now really worried!
          Worried that the best they could achieve on an abs fitted bike is 0.9g
          And worried that they could only get one g out of a modern passenger car.
          The test and data that I have seen rate a modern car such as a commodore with good tyres on good dry surfaces at one point two Gs deceleration. The data I gave was peek G deceleration which requires a lot of skill to maintain without skidding or lock up or abs.
          The data they have given is extrapolated from light traps over a distance including the reaction time and unless the rider came to a dead stop roll on time and is an averaged out calculation also there was no mention of the starting speed so I’m assuming it was 50kph the tests I quoted were carried out at over 100 kph . Now some body will say the speed shouldn’t matter but it does, more energy equals greater effort for longer to reduce speed and would result in a different outcome for even their test.

          1. Mr T, you are confusing down force as achieved by wings etc with stopping force. You can achieve more than a hundred gravities of stopping force by running into a wall.
            I have stopped a bike in less than a car length from sixty kph.
            And I have kept a bike upright sliding through sixty metres of oil until I had a choice of either keep going through a red light or put it down and kick it away from me and hope my jeans had enough friction to stop me before I hit the traffic. They didn’t but fortunately everybody had stopped because they saw two cars and my bike go sliding through the intersection before me. This was at 20 kph or so but on a steep downhill road.

  3. It’s not so much rubber contacting the road as rider skill. It’s much easier to learn how to do a hard stop in a car than on a bike. Cars have come a long way since the 4 drum systems in the 70’s and have cought up to and in some cases can better a bike.
    There’s too many variables to make a blanket statement about one being better.

  4. “…..chose 100 volunteer riders to carry cameras so they could study their behaviour. They recorded more than half a million kilometres of riding which included 30 crashes…..”

    Out of 100 riders studied for an average of 5000km each, almost a third of them crashed? 😮

    (I guess some may have crashed multiple times)

  5. lets do a comparison between cars and motorcycles in rear enders then make up our minds.

  8. Good topic this one firstly I always ride either the left or right hand tyre track as you say pretty much all the time but the one thing I tend do all the time is look 3 or 4 cars ahead so I can pick up what’s actually going on in front of me it’s not a perfect system but it’s saved my butt quite a few times over the years.

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