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SCIENCE OF BEING SEEN - Positioning approaching a vehicle Pt 1

*** SCIENCE OF BEING SEEN *** Positioning approaching a vehicle Pt 1

Here's the most common crash scenario involving a motorcycle - it's the intersection (or junction) 'Sorry Mate I Didn't See You' SMIDSY where the rider fails to stop when a car emerges from the nearside - the rider's left-hand side here in the UK.

And here's why we should make our FINAL approach to such a junction as far away from the emerging vehicle as we possibly can.

Effect of different positions on the SMIDSY collision

It's all to do with the fact that the car doesn't block the road instantly - it has to start moving forward, and it takes a moment before it completely blocks the lane ahead of us.

Let's assume that when the car starts rolling from the stationary position (GREEN), it takes ONE second for the driver to start the vehicle moving.

After TWO seconds it's in the moved forward to the ORANGE position.

And after THREE seconds it's in the RED position and completely blocking the lane.

So, let's look at what happens if the rider is positioned:

:: left-of-centre in the lane

:: centre of the lane

:: right-of-centre in the lane

Let's assume all three bikes are travelling at the same speed, and that each rider has an equal ability to stop the machine. Let's also assume that each rider detects the car moving almost instantly, and if we take each rider's reaction time and add it to their best stopping distance, they'd actually come to a stop just the other side of the junction. And finally, let's assume from the moment the car begins to roll, it would take the rider TWO SECONDS to bring the bike to a standstill.



The Survival Skills ethos is to provide useful information for all riders at any level of development and skill. If you find a post useful, SHARE IT WITH YOUR BIKING FRIENDS!

That way, we ALL benefit!


Motorcycle rider approaching a junction with a waiting car on the left

It's fairly easy to see the results.

Remember, it takes TWO seconds for the car to reach the orange position.

The rider of the green bike who starts in the wide position is well clear of the orange car - collision averted.

The rider of the orange bike who starts mid-lane passes just ahead of the orange car - near miss.

The rider of the red bike who starts in the nearside position hits the front corner of the orange car - SMIDSY.

OK, in real life, there are plenty of variables - whether the driver boots it out of the side road, how fast the riders are moving, whether they are all equally attentive and have snappy reactions or are half-asleep...

...but hopefully you get the picture. Moving further from the 'Killing Zone' where the collision COULD occur by maximising our clearance from the immediate threat is almost always a good idea.

Advanced motorcycle riding isn't always that difficult.

Next time - what about the 'forgotten SMIDSY' when an oncoming car turns across the rider's path INTO a turning?



SOBS is my in-depth investigation into the 'Sorry Mate, I Didn't See You (SMIDSY) collision between motorcycles and other vehicles.

Created for the fire services 'Biker Down' course, it's based on science, not speculation. I aim to quash some persistent myths about how and why junction collisions happen, and show how motorcyclists can employ simple techniques to stay out of trouble!

BUY THE SOBS e-book -



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