|factors in choosing lane position||Eli Damon||4/20/12 1:52 PM|
I thought that some of you might find this useful. In preparing for a
presentation I'm giving next week, I made a list of all factors I could
think of that influence the choice of a lane position.
Also, let me know if you have anything to add to the list.
|Re: factors in choosing lane position||Willie Hunt||4/20/12 2:05 PM|
The list looks good! One factor that I use is positioning for the
inductive traffic light sensors, when other motor vehicles are not
present to trip the lights.
|Re: factors in choosing lane position||4ank||4/21/12 4:56 AM|
|Re: [BicycleDriving] factors in choosing lane position||Alan Forkosh||4/21/12 10:17 AM|
To the list of surface issues, I would add some construction issues:
parallel seams and cracks
Alan Forkosh Oakland, CA
|Re: [BicycleDriving] factors in choosing lane position||Serge Issakov||4/21/12 2:47 PM|
Glass, branches, goatheads.
|RE: [BicycleDriving] factors in choosing lane position||Mark Ortiz||4/21/12 7:40 PM|
Minimizing lateral moves.
Here’s an example: on the north side of Charlotte, NC, 49 crosses over I-485. This is a half-diamond/half-cloverleaf intersection: all on and off ramps to 485 are on the northwest side of 49. On the east side of 49 is a railroad right of way. Southbound on 49, you have a light before and after the overpass, then a third one shortly after that. 49 has four lanes (two each way), plus various RTO lanes and turn pockets.
Approaching the first light, there is an RTO lane leading to an on ramp, and two through lanes. On a bike, you need to be somewhere in the right through lane. As soon as you get through the intersection, a feeder lane comes in on the right, and the road goes to three southbound lanes across the overpass. For a short distance, across the overpass, that new lane is now the rightmost lane available to through traffic. Under a FRAP law, you’d have to cross that lane and go down the right side of it.
As soon as you get to the end of the overpass, that rightmost lane becomes an RTO lane, feeding the on ramp for 485 eastbound. On a bike, you can no longer use that lane; you need the middle lane again.
So to comply with a FRAP law, you’d be compelled to make a rightward cross right before the overpass starts, and then a leftward one immediately afterwards.
But that’s just silly.
What I do is go just into the rightmost lane after the first light, and go down the left edge of it, just right of the lane divider line. That lets motorists by me on the right, often with two wheels on the generous paved shoulder (an illegal move for them in NC, but at least I’m legal, and nobody cares about their pass because it obviously creates no problem). When the rightmost lane becomes RTO, I just go a little to the left of the line, and I’m in the proper lane for my destination, without having to cross anybody’s path.
I generally take the middle of that lane then, because after the light immediately following the overpass, that lane too becomes RTO, for a next light that follows very promptly.
This strategy is perfectly legal in NC because, Beck Michaels notwithstanding, I am only required to be somewhere in the rightmost lane then available for travel across that overpass.
|Re: factors in choosing lane position||#328 Gordon||4/24/12 9:42 AM|
A good, extensive list, including the ideas in the replies.
One suggestion regarding the presentation. There are 2 kinds of
locations where cyclists need to decide where to position themselves:
at intersections, and on the roadway between the intersections. (These
are in 2 of the 5 "Principles of Driving in Traffic" in JF's EC.)
Some of your points cleanly fit into one or the other; e.g. "edge
features" with the roadway between intersections. Others do not. If
you could arrange these to indicate which location(s) some pertain to;
or, indicate which they pertain to, (mark with an I, or B); that could
help non-cyclists or beginners understand our logic.
Will you have diagrams with this?
On Apr 20, 4:52 pm, Eli Damon <pub...@eli-damon.info> wrote:[ ... ]
|Re: [BicycleDriving] Re: factors in choosing lane position||trevor||4/24/12 8:11 PM|
Good idea. Besides "intersection" and "midblock", I would also add "interchanges" (merge/diverge and union/divide). The "right lane" is often the "wrong lane", even if not "preparing for a left turn". We all know that "right lane" means the rightmost one leading to where we're going, but they don't all know that. Interchange between two major roadways often have these extraneous side lanes that should be ignored when determining the proper through lane to use.
Police officers and freeway designers always want bicyclists to wait until the point of the diverge and cross a bunch of lanes at a 90 degree angle instead of merging early. In some cases, that may have to be very early depending on average speed of traffic and number of lanes with higher crossing conflicts.
|Re: [BicycleDriving] Re: factors in choosing lane position||Bob Shanteau||4/24/12 9:33 PM|
On 4/24/2012 8:11 PM, Trevor Bourget wrote:
I know what a merge/diverge is. But what is a union/divide.
BTW, last I checked, images are allowed in BicycleDriving. Perhaps we
|Re: [BicycleDriving] Re: factors in choosing lane position||trevor||4/25/12 12:37 AM|
Bob, a merge/diverge is where two lanes become one or one becomes two.
A union/divide is where two roadways join or split. The number of lanes doesn't change, but what an edge becomes a middle or vice versa.
Freeways often have unions and divides, surface streets less frequently, and when they do a union is often followed shortly thereafter by a merge, and a divide usually precedes a diverge.
I'll try to find some example maps to illustrate each of those scenarios, but I'm a firm believer that a thousand words is worth a picture.
Those terms, by the way, were part of Effective Cycling (Road 2) training materials.