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Talk about lucky, this guy went down on Mulholland Hwy...

Let's see, trying to ride a fully dressed HD as if it were a full on Track Bike, wearing sneakers, jeans and a white tee (at least he wasn't wearing a wife beater, although I'd bet dollars to doughnuts he has a closet full of them) and only a half helmet for protect..........all I can say it is lets hope he never breeds, coz he definitely came out of the low end of the intelligence gene pool. And while it is impossible to legislate away stupidity, it is possible to breed it out.

He was leaning his body away from the turn, counter leaning, which increases the lean angel of the motorcycle. Considering how slow he was going, if he had been leaning off to the inside of the turn I think he would have had plenty of lean angle and would not have been grinding hard part. If he had not levered his rear tire off the ground by grinding hard parts, he would have had more than enough traction to finish that turn. It is not like his tires slid out from under the moto.

Safe Travels,
Richard

He should have been in a lower gear...and...stupid fool had his foot on the ground. Expensive lesson to learn.

I read reviews of those big Harleys, and some of them apparently have very little cornering clearance. Hanson is right, he blew the little clearance he had by not leaning to the inside. His arms and shoulders are also tense and locked up - he's fighting his own muscle tension as well as the bike.

I know guys who can get decent handling out of a Harley bagger, but most of them have had experience on other kinds of bikes. I can't imagine someone with only experience on a StreetGlide and nothing else learning to execute sport riding techniques.

I saw this video a long time ago. Aside from having no gear for protection, I just kept thinking the mistake was all in that fearful foot.... If he'd kept it on the footboard, don't you think he would have gotten through it? Or do you think the hard scrape bumped his foot out there?

Don't know if he would have made it through, but he seemed to have slid the foot out himself...

I thought if you were going slow it was better to counter lean? I have been doing that on slow start turns out of driveways and it seems to help keep me on an angle. he needed to get away from the edge and leaning helps close the turn but he had no clearance, what were his options in this case? I know i don't know much but i would say his issue was speed. He couldn't lean enough to keep from going wide so his only option would have been a slower speed. Being reckless and taking a big cruiser that quick cost him. Lucky for him it didnt cost him a broken ankle.

JWF505 wrote:I thought if you were going slow it was better to counter lean? I have been doing that on slow start turns out of driveways and it seems to help keep me on an angle. he needed to get away from the edge and leaning helps close the turn but he had no clearance, what were his options in this case? I know i don't know much but i would say his issue was speed. He couldn't lean enough to keep from going wide so his only option would have been a slower speed. Being reckless and taking a big cruiser that quick cost him. Lucky for him it didnt cost him a broken ankle.

Gravity is always acting on the motorcycle and rider through their combined centre of gravity. The rider can change that centre of gravity to some extent by shifting their weight to the inside of the turn or to the outside of the turn (counter leaning). When riding straight down the road in an upright position, gravity is pulling the rider and the bike straight down and everything likes to keep moving in the same direction, that is called inertia. When you go into a turn, then the tires of you motorcycle are forcing the motorcycle into a new direction by friction between the tires and the road and this is necessary as a force must be applied to get the bike to do anything other than to continue in a strait line at the same speed. Think of swinging a rock on the end of a string around your head in a circle. You can feel the rock "pulling" on your hand, and we call this centripetal force but in fact you are pulling on the rock which is why it is moving in a circle instead of in a strait line. If you let go of the string, then the rock will travel off in a strait line as you are no longer exerting a force on the rock to make it "turn". The faster you swing the rock, the higher the centripetal force.

Motorcycle and rider experience the same forces, gravity pulling you down, and the centripetal force pushing you out. When you lean your motorcycle and body into a turn, you are balancing these two forces so that you neither fall over to the outside of the turn or to the inside. The faster you go, the greater is the centripetal force while gravity stays constant, so the more you must lean to balance these two forces acting on the motorcycle and rider. How fast can you go around a curve? Another way of asking this question is how far can you lean your motorcycle? Different motorcycle have different maximum lean angles before they start to grind hard part, but these forces do not act on just the motorcycle, they also act on the rider and the rider can move the centre of gravity of the combined motorcycle and rider by moving his body. If he moves his body inside, hanging off, he can effectively decrease the necessary lean angle of the motorcycle because he has changed the centre of gravity a bit. This is why racers lean off in order to maximize the available lean angle of their motorcycles.

What then of counter leaning?

When going slow, the centripetal force is very small and the bike does not need to lean hardly at all to make a turn, but how tight can you turn if your handlebars are locked to one side and the bike is upright? Think of dog walking your bike through u-turn. So what is going on? Think of rolling a paper towel tube on a table... it rolls is a strait line. Now role a red-solo cup, and it makes a tight turn because it is not a cylinder, it is a conic section. The top of the cup has a larger radius than the bottom of the cup and it is this difference that causes the cup to roll in a tight turn while the paper towel tube, a cylinder, rolls strait. Think of you motorcycle tire as being the end of the paper towel tube, it is upright, and the end of the red-solo cup, it is leaned to the inside. When a bike is upright, it behaves like the paper towel tube, a cylinder but when it is leaned over then it behaves like the red-solo cup, a conic section. The more you lean the bike the tighter it will turn, but there is no large centripetal force acting on the bike to keep it upright. Please remember, to go faster in a turn we want to hang off to the inside to maximize the ground clearance as we balance the centripetal force against gravity, but the opposite is true when trying to make a very slow tight turn where we are trying to maximize lean angle in order to make a tighter turn when there is hardly any centripetal force acting on the motorcycle. To increase the lean angle in slow speed maneuverings so that we can make tighter turns, we counter lean, we move our bodies to the outside of the turn so that we can lean the motorcycle to the inside of the turn.

All of this is quite a bit of a simplification as we have not addressed items like force vectors, or the normal force with respect to the plane of the surface we are riding on, or the forces of a turn compressing the suspension of a motorcycle which decreasing ground clearance, this is not a physics lesson, but a good rider is not just a static passenger on the motorcycle. A good rider will understand how to move their body to get more out of their bikes when riding fast or riding very slow. Both techniques need to be utilized when appropriate, but this is not that easy. Many moto-cops are trained for slow speed manoeuvring and will counter lean even at speed, this is what they have been trained to do, and many regular riders never learn how to counter lean in slow speed manoeuvres which is why we see people dog walking their bikes in a u-turn. More accomplished riders will do both.

To be very clear, I understand how to move my body on the moto and why, but I am certainly not a good or talented rider. I am, however, a better rider than if I did not comprehend basic motorcycle dynamics, when to hang off to the inside and when to counter-lean.

I apologize is this post should come across as condescending, I am only trying to be informative.

Safe Travels,
Richard

@Hanson

Thank you for the lengthy and detailed explanation of the physics behind a lean. That was a doozy of a read. i went through it 2 or 3 times to comprehend it all and i doubt i have fully even still! While i fully intend to learn and understand all of the theory you spoke of I for starters am still a bit confused about this particular situation and how I can learn from it.
My understanding of things in a lean/turn are as follows:

Stay off the front brake, it will eat up your limited traction and compress the fork and thus lower you even closer to the ground.
Even throttle with perhaps a bit of rolling on to raise the front fork and keep you moving through the turn without the wobbles of slowing too low into a gear.

At low speeds you want to lean away from the turn to increase your lean angle while at decent speeds you want to lean into the turn to help keep your turning radius short and avoid running wide into the other lane or the shoulder. Also this increased lean helps you maintain speed and that can be fun.

I am not going to mess with counter leaning at higher speeds yet, ill stick to leaning into the turn if I am in a speed of above 15mph or so, basically any turn I make out of first gear. When making slow uturns I have found counter leaning to be the only way to complete the turn without putting a foot down.

I think in due time with some research and some visuals I can better understand all of what you were speaking about. For the time being I think I will stick with just knowing what to do!

Counterlean at low speeds and lean in at higher speeds.

You say he should have leaned into the turn, that would have decreased his lean angle in a slow turn? Well I will have to try that a bit on my next day off, as it would seem to me that it would put one off balance and possibly have the tires slip out from under since there is little centripetal force keeping you upright. I may have to play with leaning both ways more to feel the difference and learn for myself.

You seem to know what you are talking about, so if he had increased his lean to the inside to keep the bike less leaned in, avoided the hard contact and he would have finished the turn. My question is and maybe it is just reading into it too much and thinking too much about a simple turn, but wouldn’t have been even better if he had downshifted into a lower gear and come into the turn at a lower speed? He would have been able to counter lean and maintain the turn if he had just done the appropriate planning and actions before the turn.
I
t may be a bit silly sounding but one of the things they said in the BRC was ‘and expert rider uses expert judgment to avoid using expert skills’

I really liked that part, trying to think ahead and know what is coming and what needs to be done so you can take the easier path and avoid having to make emergency corrections. In this guy’s case he did not head that advice and came into this turn to hot. Right?