Spinouts, motorcycles and skill

Well that will probably work for some people, but it's not going to work if you've already been riding for a while and actually know where the cornering limit of your bike is.

In fact if you're BOTH going fast (i.e. the corner had a large radius) AND taking a reasonable line through the corner (i.e. towards the inside of the lane, not the outside) THEN you've got quite a bit of space to play with getting upright and braking hard in a straight line. I've been motorcycling nearly every day for 25 years and I can tell you that straightning up and braking HARD really helps.

Let's look at some numbers.

Suppose, for example, that you're doing 80 mph (130 km/h, 36 m/s) and you'd need a 45 degree lean angle (1 G lateral acceleration) to get around the corner. From a = v^2/r the corner radius must therefore be

36^2/9.8 = 132 m. Suppose you're at the inside of a 3m wide lane, at the point you decide to straighten up. What distance will you travel before getting to the outside of that lane? There is a right angled triangle with you at the right angle vertex, the second vertex 132m to the side of you at the center of radius of the curve, and the third vertex (132+3) m from the center. Using Pythagorus, the distance from you to that third vertex is sqrt(135^2 - 132^2) = 28.3 m.

If you brake at 1G (instead of turning) for half a second you'll drop your speed to 31.1 m/s (112 km/h, 69.5 mph) while traveling 16.8 m of the available 28.3 m. At the same time you've dropped your 1G (45 degree lean) cornering radius from 132 m to 98.7 m (a 25%) reduction. Alternatively, you can now take that 132m curve at only 0.75 G (37 degree lean angle).

Either way you look at it, you're much better off now than you were half a second earlier.

-- Bruce

The real challenge is when you've committed yourself to a turn only to find there's sand/gravel strewn on the roadway, and if you ride for any length of time, this one'll eventually get ya. Another one is where someone in a car, who is apparently completely oblivious to your presence, places their mostly stationary vehicle directly in front of your moving bike.

There's physics involved in motorcycle riding that put you on the losers end of the stick regardless of any "mind over matter" :^), best to be paranoid at all times when riding. The minute you actually begin to enjoy the ride, some A-hole comes out of the woodwork and almost ends your life. But everyone's different, I know folks that've ridden incident-free for over a decade, yet others buy the farm in their first year. IMO, open highway criusing is the safest, city riding is the worst.

there's sand/gravel

eventually get ya.

If you are riding to the Vanishing Point, then this will never pose a problem. It is only when you ride faster than your sightlines allow that you will be caught by this one. Of course, many many many people frequently outride their sightlines, and then are surprised by accidents they "couldn't avoid". That's like saying you lost it on a corner that had a decreasing radius because your car was out of traction because you were entering the turn at

100mph. Not really an accident at all.

to your presence,

This is more likely. Again, it is not a given. A dozen years of riding in all seasons (and a little snow and ice to boot) and I have yet to be hit by a car.

city riding is the

Stats back you up for both car and bike accidents. Limited access highways are statistically the safest.

Exactly.

If you're riding or driving is 'reasonable and prudent', when will you ever find yourself entering a curve so fast that you know you won't make it?? If you clobber some pedestrian walking on the outside of that turn, your world as you know it is about to come to a screeching end.

Take it to the track.

jw milwaukee

On Mon, 2 Aug 2004 08:58:13 -0700, Cam Penner

Actually my point (although probably not well made) was aimed more at making the distinction between riding at a prudent, confident pace on familiar roads, v.s. the same confident pace on unfamiliar roads and getting surprized by a sand-wash over the pavement. Since that situation is never a problem in a car, the novice biker tends to get bit by it.

I rode a Kawasaki H2 (750cc, 3 cyl., 2-stroke) for about 3 1/2 years. That machine was one part powder keg and one part barrel 'o monkeys and was incredible fun, but I felt like I had a target painted on my chest or something. Every time I'd go for a spin someone would come close to taking my life. I enjoyed riding that bike more than anything, but I had to give it up. Oh well, I like my Outback Sport too. :^)

the distinction between

pace on unfamiliar

situation is never a

It's never a problem if you ride to the Vanishing Point. Familiar roads can NOT be ridden ANY faster than unfamiliar roads without sacrificing safety. Most people go faster over familiar roads, but are giving up safety in the process. You CAN NOT safely outride/outdrive what you can see no matter how many times you've been down that road before. Sand, oil, deer, children, lumber, etc. can all be lurking around the very corner you just rode through 2 minutes ago. Roads change. Even familiar ones. If you can't identify and avoid all hazards in your line of sight, and you can't stop within your line of sight, you are setting yourself up for an "accident" that is really just poor driving/riding to begin with.

machine was one part

like I had a target

come close to taking

up. Oh well, I like

Now you're on the other end of the crosshairs. ;)

The longer I ride, the fewer close calls I have. I see things happening sooner, and take the necessary steps to avoid close calls before they happen. I don't even notice myself doing it most of the time, but there is no other reason for it.

Ain't two-strokes fun though? I love the look on people's faces as my "little" 350 pulls away - like a rocket.

For those unfamiliar with the Vanishing Point technique, here's a website with a summary of it. At the bottom of the page is a link to a bunch of examples using real life road pictures.

Thanks Cam. Danny

Good reading. Thanks!

-Matt

What? Leaning a car? But seriously folks ... Frank Gardner, Australian race driver and extraordinary engineer wrote a book called "Drive to Stay Alive". Doubt if it's still in print but I still have my old copy. Dealt with a lot of situations but with a defensive focus. Learn about point fixation, getting a car unbalanced or just plain bad technique and practice. You'll be in a better position to go and condition yourself to avoid those things in a controlled situation BEFORE an emergency. Use a trackday or an advanced driver course or a very big paddock with no trees or burrows. Condition your responses so that the RIGHT response becomes your panic reaction.