Carving it up on the street
There's an idea floating around that it is safest for street riders to only use half of their lane, the right half.  The idea is that this will keep the rider safest from oncoming traffic crossing over into the rider's lane.

Specifically we're talking about right hand corners we can't see around. Lefts too, but much more so rights - well, at least the US crowd is.

So, I approach a right hand corner, at what I believe to be a safe speed. I set up near the double yellow to maximize my line of sight. I plan my arc based on paint line arcs, tree line, other visual inputs, and just plain guessing. My arc will take me from the double yellow to the white line. I pick a turn point and flick the bike in.

As I flick the bike in, I spot a pickup truck coming the other way in my lane. As I'm already turning in, I turn in a little tighter and avoid him.

Now the issue being stated here is that my choice of lane position puts me in danger of being hit by that truck. That's simply not the case.

The only thing that would put me in danger of hitting that truck is riding too fast for the available sight distance - the amount of space between when I first see something and when I get to it.

On entry to a corner, the arc of an on coming car is naturally divergent with the arc of the motorcycle. On the exit of a corner, the path of the motorcycle is naturally convergent to the path oncoming car. The danger is not entering the corner but exiting the corner.

With a wide entry it's easier and safer to adjust your exit position than when using a low entry. In general a wide entry is safer and better for the overall performance of the motorcycle - performance that only matters on the track or in emgergencies.

The exit of the corner is what you can't see. Yet using a tight entry will limit your line of sight - reducing available reaction time, require a longer steering inputs - reducing traction, destabilizing the bike, and make your exit wider - putting you directly in the path of the danger you can't see.

Reasons for on coming vehicle in your lane impact:
at corner entry = riding too fast for sight distance
at apex (white line) = screwed all around
at exit = exiting the corner too wide and riding too fast for sight distance.

I have read one good reason for using a tight entry to a corner and it was combined with a tight exit strategy too. That was from Reg Pridmore describing riding on very narrow roads in either Sweeden or Switzerland. To me, that's just being smart about the environment you're riding in and not a rule that applies everywhere
For left hand turns you really don't wan't to be right on the double yellow at the apex unless you're absolutely certain it's clear.  In a left hand turn, if the tires are at the double yellow your body will be 2-4 feet into the opposite lane.  That's just not good when a Hummer is coming the other way.
Published Saturday, September 30, 2006 9:21 AM by Greg Gorman
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Comments

# re: Carving it up on the street@ Tuesday, October 03, 2006 1:21 PM

This debate is indeed ongoing. :)

I must agree that lining up on the outside of the turn arc is appropriate, even for right hand turns.  As you stated, I think the popular argument to the contrary insists that the rider is in a better position to avoid traffic that is approaching left of center.  I’ve even seen videos or pictures that attempt to substantiate this sort of position, where a rider is (nearly) clipped as the bike is negotiating a blind right hand corner.

The problem here is that in those cases where a rider suffers a near miss in a right corner, the reason that the miss seems so near and that the incident seems so surprising is because the rider has selected a line that offers more limited vision of the oncoming traffic.  When positioned on the inside of a blind corner, an approaching vehicle will indeed appear very suddenly, because we have self-imposed a limited sight line through the turn.

By selecting a line at the double yellow, then delaying the turn-in as appropriate (most of us have a tendency to turn-in too early for all corners, which puts us right back in the blind again on those tight right-handers), the rider is in the optimal position to see and avoid oncoming traffic (or obstacles in the road, etc.).  And of course, it’s critical to look through the turn (as far as you can see), beginning just before you flick into the turn.

And the idea of obstacles brings me to the next point I raise in this little debate.  What if it’s a very tight right hand corner with a big rock (or a stalled vehicle) sitting in your lane just beyond the apex?  And let’s say traffic is heavy in the opposite lane.  How does that inside approach (leaving you blind to the obstacle until the very last minute) sound then?

Again, and as you've stated here Greg, I think the optimal line is on the outside, delay the turn-in, make the dive for the apex and make it happen quickly (smooth, but abrupt… don’t slowly drift over), and most importantly, keep looking around the turn as far as you can see.  And of course, on the street leave a margin of cornering and speed so that you can react and avoid unknowns.

Having said that, if an approaching vehicle carries excessive speed, then it’s certainly possible that even the optimal approach will still result in a collision.  But in these extreme cases, our line position on approach is really not relevant.  And an inside line will likely be no safer.

My two cents. :)

by DeltaHotel

# re: Carving it up on the street@ Wednesday, October 04, 2006 9:19 PM

The other reason videos of a incidents like this are so surprising is because of the small field of view of the video camera.

Really anytime you are almost hit by a car, it is an extreme situation.  It's almost happened to me several times.  But that's several times in what, 100,000+ miles of riding?  In each case, what saved me wasn't what line I was on, it was being aware enough to see the situation and change my line and/or speed.

It's about being aware and being able to control.

by Greg Gorman