The anotomy of a crash!

Have you every had the misfortune to find yourself lying next to your bike, shaking from the adrenaline and endorphins coursing through you, and wondering just how the hell you fell off? If you haven't. Well done, your part of a small and exclusive club, either that or Fred Gassit's quip, "If you ain't falling off you ain't going hard enough", may apply.

If like me, you've had that fall, or falls. They probably bug you to this day. Everyone falls off, with these unstable two wheeled things we like to ride it's only a question of time and distance before you do. Yet what happens when you have enough data from your bike to find out? What would you change?

Lucky for me (and you if you keep reading) I have had  a data logger fitted to my race bike for about six years. A data logger can show you just what you did differently on a quick lap, to a really slow, and often painful lap. I know we are talking a race track here, but don't be fooled this is track only.  Manufacturers in the future may put into their frankly under stressed ECU a recording mechanism to trap just what the hell happened if something goes wrong. Manufacturers are more interested in how their product failed in a mechanical sense than why it fell over. The implications are interesting though. That the ECU may be able to tell someone, insert the Police, lawyers etc, just how fast you and the engine were going, and how much you might have slowed down before the ouchy moment.

My data logger is an AIMSport GOLD BIKE. This unit has eight channels to record various inputs. The default inputs are things like road speed, a gyroscope, engine speed. I have added in a couple more including recording the throttle position sensor or TPS, exhaust gas analysis (lambda numbers), and engine oil pressure warning systems. Between the road speed, and horizontal gyroscope the software supplied by AIMSport can generate a track map, track sector breakdowns and allow for easy comparison on lap to lap.

Even with this information, I still sometimes find myself sitting in the dirt looking at a motorcycle and pondering, what the? So lets have a look at a crash from a data point of view, no wondering, just the facts.

Morgan Park low side, May 2010, Bike: Bimota db1 Beta EVO

This fall took place on the second lap of a race, when I had got myself free of my competition and was looking to make a gap on them. So lets cut into some data, thankfully graphically represented.

Morgan Park track map

First thing to understand is the track layout. The image here indicates the shape of the Morgan Park track, the corners are numbered to match the sections of the track we will investigate latter. The small arrow at the top of the image indicates not just the track direction but where the infrared triggering beacon is placed. I try to place it on the start finish line, so my lap times are as close as possible to those on my time sheets. Its a tight race track in its current configuration, top speed of the Beta Evo 195kmh on the front straight.

The next image shows in red my best lap of the track, and in black my crash lap. Across the top of the graphic you'll see a smattering of green, red, blue sections, the red and blues are numbered as corners, as per the circuit map. It can be clearly seen that the black  line plunges to zero in turn three as I fall, and then get going again.

Best lap vs Crash lap

The facts: So how did I crash?

Turn three opps

To allow a closer look at how, I've provided the detail image of just the run into turn three. Black trace is speed from my best lap, red  speed from my crash lap. I have added in the gyro readings for comparison as they tell much of the story, the blue line is from my best lap and the mauve line from my crash lap.
As can been seen from the image. I carry to much speed into turn three, 10kmh quicker than my best lap, hence the red line in turn three is way above the black one (marker A). I apex later as can been seen by the mauve line reaching its peak after the blue line (marker B).  At this point the front tyre screamed enough and let go. I slide into the dirt, but manage to recovery.


The reason:  So why did I crash?
To find the cause for my eagerness into turn three on this lap, we need to go back further in the data to turn two (marker C). Here you can see the black speed trace plummet from the red. Even though I had set a good first sector and one of my best top speeds for the weekend. The reason I shut the throttle here was due to seeing yellow flashing lights, a caution flag in effect on the pedestrian bridge crossing turn two. A caution would not put you off that much you might think, but turn two is blind. Not only blind, blind and fast. I'm using fourth gear through this left hand sweeper. As such I was expecting to find a rider or bike obstructing the track. The speed trace shows I was 20kmh slower until I rounded the bend and could see nothing on the track. From there I get the gas back on from the middle of the turn two section. As a result the black line passes over the red line only at the very end of this straight (marker D). That's me braking latter and harder into turn three desperate to make up time.  This is also where it all goes wrong and I loose the front end.

Best lap vs Crash lap

The lesson: How not to do it again!

Simple things to remember:

Don't go into a corner that much harder!
- There is an old saying, "Slow in and fast out, is better than fast in and dead out!", for me it was dead last! If I had gone in slower I would not have fallen off, so 10kmh was obviously way to fast, and way to late to get the bike turned. A fall like this has another added benefit if you want to see it that way. The marks my bike left on the track made a very good indicator as to where I should be coming off the corner. No longer turning! Odd to see it as a bonus I know but whilst I could see them I was using them.


More complex things to remember:

Do not allow myself to be flustered and frustrated after having my progress slowed.
- Its extremely hard to stay cool, calm and collected when you're strung out on testosterone and all those other natural drugs, and freaking out you might not win. Calm is fast. So keep calm, or cool, Zen, what ever you want to call it. It was a silly mistake for someone with my experience, hence I was kicking myself the rest of the weekend.

Check behind you, see if the opposition have closed the gap.
- Why did I not look behind me? Well, on a race track I never do. What's in front is what matters, those are the guys you need to pass. I also get a big personnel kick when riders start looking back, I take it as a sign of weakness. So I don't do it. In this case, a simple look over my shoulder would have told me I was in no danger of being passed, and possibly avoided the crash. Also, I knew I could lap faster than the guys behind me. Being in front I still had the capacity to get away unhindered, being in the dirt I was playing catch up. The lesson for me here is try to be more flexible in my thinking, looking back is an option to keep in mind.

Hope you enjoyed this little rant!!