Tuesday, May 11, 2010

How to read a corner.

This should come as no surprise but blind corners hide both hazards and their characteristics. Since we don't have x-ray vision the hazards will remain hidden until we actually get there. By looking for clues, however, we can get some advance idea of the corner's direction and make-up.

Hopefully we're all on the same page. The page that says maintaining as large a visual lead as possible is critical. That's because we're scanning for critical information. Notice the tie-in provided by the word "critical". I've typed that word three times in three sentences. Must be important. The earlier we get information the better. During that scan we're looking for clues that will tell us something is upcoming long before our eyes can actually spot it. Watching the painted lines on the roadway can give us early clues about the corner. The lines will tell us about which direction the road turns, how tight the turn is, and a bit about the camber of the corner.

Scan the fog lines on either side of road and the yellow line in the middle. Look at the point where the lines converge and disappear from our view. The clue about the corner lies in that place. You're looking for the spacing between the lines. With a picture being worth a thousand words, take a look at these few thousand.

In the photo above the lines maintain a relatively constant relationship to each other. There's a fair amount of space between them. This corner will have a fairly constant radius. It's not what you would call a particularly tight turn or sharp corner.

In the corner above the lines converge more quickly but don't actually look to be touching. The curve is tighter than the first one.

In the photo above the lines seem to almost touch where they disappear between the tree on the left and the bushes on the right. That's a clue that this turn is going to pretty tight. By now the sun was shining brightly and washing out the lines. It's harder to see than I wanted it to be. Sorry, but you get the idea.

Some riders use telephone poles and the wires they carry as indicators of direction. Just be aware that sometimes they lie as you can see below. Depending upon your particular bike, you may not want to be riding out there!

Clues are just that. Indicators but not force fields. This is a good time for a couple of reminders. Anytime we can't see all the way through a corner we have to expect the worst. Our entry speeds should be set accordingly. Better to be pleasantly surprised than to meet nasty surprises like in the photo below.

Never commit to the apex until the exit of the corner is visible. Until that point we're making a critical decision without all the information. Not a good idea, at all!!!

Reading corners and reading the written word have something in common. The better our reading skills are the more information we will have available to us. Better information enables better decisions. Next time you're out riding corners ( and I hope it's real soon! ) practice reading the lines. By the way, if there are no lines on the roadway, use the edges of the road as clues.

Miles and smiles,

Dan

19 comments:

Mike said...

Very nice post, Dan! Really great info here. Taking curves properly has to be one of the most important aspects of safe motorcycling considering it's the number one killer. At least I'm pretty sure it's number one. But you know that. I learned a lot here on this post. I have to admit that so far my approach has been to figure that I can take a curve at approximately 15 mph above the posted curve speed. That's if it's not raining. The bad part about that is it doesn't take into consideration unseen road hazards and surprises or the pesky decreasing radius curves.

Thanks again for taking the time to do this!

American Scooterist Blog said...

Great refresher! Thank you!

Harv

Dave said...

Dan

More great info thanks.

Now lets see if I can put this in to a proper question

How one enters a curve relative to the apex and speed is what determines were your exit point will be.

This is my take on the phrase outside inside outside. Am I close off base or should I park my scooter and take up knitting straight jackets ?
Thanks
Dave aka Old F

Jeffry said...

Great text and visuals. I still have room to improve in this area and will take advantage of your post. Thanks.

bobskoot said...

Dan:

I got a gentle reminder when I saw those telephone poles and wires out in the field with no road beside them.

I was briskly following along the road twisting my way and following the power lines when after one curve the lines stopped following the road. Lucky thing I still had one eye on the edge of the road.

Also another trick is to keep your eye on your GPS as you are climbing a hill, for it tells you which way the road goes when you reach the top. Also when on our trip into Hell's Canyon you are alerted to switchbacks with ample warning

I am getting better at reading those lines, whether parallel or decreasing angle, you just don't know if it is decreasing radius or not.

thanks for the refresher

bob
Wet Coast Scootin

Bryce said...

The corner itself is not the problem,
it is the individual who designed the corner, never giving a thought to two-wheeled motor powered devices.

Then too the corner itself may be fine, however foliage intruding on the line of sight, surfaces of the corner be it strewn with all manner of slippery material including
lubricants and the effects of
hydrogen and two of oxygen.

Corners be they 90 degrees, more or less contrive to pitch us from our steeds, at any velocity.

bluekat said...

Bicyclist use the telephone poles as well. We watch them when climbing long hills hoping to see them begin to dip downward again. Please, please, dip downward!

Last winter I was working on my corners. With the new bike corners are so much easier, I've gotten lazy. Time to get back to it. I'll have to make a point of looking at the lines. I haven't given much thought to how they look, or what they reveal. To me the last photo looks like the least sharp turn compared to the others. Obviously I need to work on it more. :)

SheRidesABeemer said...

I'll admit it, I just looked at the pictures. Nice curves. 8)

bluekat said...

If you're looking for ideas...I would love a post on downhill corners. :)

Charlie6 said...

Blind curves with cliff on the far side and rock wall on your side are the ones I dread.

Factor in gawking tourists in cages driving near or over the centerline and life can be interesting when you're on a motorcycle.

Good info as the others have remarked.

I'll just add, keep the revs up, engine braking is your friend, gravity is not on downhill runs.

jason.ewert said...

But what about those unseen road hazards! How do you get through them safely? I like to practice standing the bike up mid corner, scrubbing off speed then diving back into it.

(don't try this on a blind corner!)

I find this to be a good method of last resort. Any thoughts?

irondad said...

Mike,

You are correct in that a failure to negotiate corners is the leading cause of fatalities in Oregon's riders. The crash happens in the last third of the corner. Either the rider goes wide and hits a solid object or they cross into oncoming traffic.

This indicates that the riders were surprised by the curve or something in it. They weren't looking far enough ahead.

My goal is to give riders as many tools as possible to take care of themselves. So I'm pleased you found this of value.

Take care,

Dan

irondad said...

Harv,

You're welcome. Thank you for the positive comment.

Dave,

Provided our speed allows us to maintain control of our path of travel, it's really the apex that controls where we exit.

We should always enter a corner to the outside unless there is some extreme mitigating circumstance.

An early apex will tend to throw a rider wide on exit. A late apex will tend to pull a rider in closer.

That's the short answer. It's a great question and should probably have its own post to do it justice.

Jeffry,

Thank you for letting me know this was helpful. I'm pleased that it was. We all need to keep improving. Even instructors become students as required.

Take care,

Dan

irondad said...

Bobskoot,

Thank you for sharing your experience. I always appreciate it when somebody lends credence to my words!

As to the decreasing radius curves, the adage holds true. If you can't see the exit of a curve, expect the worst. Stay to the outside until you can actually see the exit. Simple, but powerful!

Bryce,

Exactly! Thus the importance of making sure we know how to deal with corners. The real world is never ideal.

Bluekat,

Thus the advantage of a motor. Doesn't matter if the power lines go up or down!

That last curve is actually two in one. The gentle curve to the right leads to a much sharper corner just out of sight.

Take care,

Dan

irondad said...

Gail,

Thank you for stopping by! I've been missing hearing from you on your blog. Congratulations on the new car. Snazzy!

Take care,

Dan

irondad said...

Bluekat,

I would be more than happy to do a post on downhill corners. Just guessing, but I'm presuming you must be taking Skyline Road out of Salem. Both Vitae Springs Rd. and Skyline have downhill corners. Since you seem pretty familiar with the roads near the wildlife refuge, I'm guessing Skyline is the most used one. That one is also tighter and can be more scary at times, isn't it?

What might be more fun is to go ride with you on Gap Road coming into Brownsville from the South. Not far from you that way. There's a couple of interesting downhillers in that direction. Afterwards, you could write the post on your blog. Just a thought.

Take care,

Dan

irondad said...

Charlie6,

I can almost feel the shudder from the roads you talk about. Yikes!

You're right about gravity not being a friend. On the other hand, the trick is to keep the throttle open enough to avoid overloading the front tire. Engine braking does the opposite if done at the wrong time. Tricky sometimes.

Jason,

There is some validity to doing what you describe. If a rider is doing that to combat entering the corner too quickly, then the key is to fix the entry speed next time.

The same goes for unseen hazards. The key would be to spot them as soon as possible to mitigate the surprise factor. If we can't see through the turn, we have to expect these kind of things adjust our speed accordingly.

On the other hand, crap happens, as they say.

When crossing areas of low traction in a corner, straightening the bike is appropriate to get rid of lean angle. We straighten, ride through, then lean for the corner, again.

If you need to scrub speed off quickly if something does go wrong, the technique you describe is absolutely correct. With the caveat that it takes space to do so. One's execution needs to be spot on.

Actually, your question opens a door to many things like which path of travel do we take? It deserves its own post like Dave's comment. Hmmm...

Take care,

Dan

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bluekat said...

Actually, I use Battle Creek Dr. There is one S curve that heads downhill coming out of Salem. Not terrible steep or sharp, but enough to know I need to work on it.

Ah yes, Gap road is our route to Eugene. Very fun going south...corners up and straight (more or less) going down. Oh wait, you said "from" the south. That's the hard way! Ok could be fun...I think...shakes head, muttering underbreath. :)