Originally Posted by
genec
You are not following the thread... yes I am making some big assumptions... one big assumption is that cyclists make up 20% of traffic... unlike today when they are a scant almost 2%.
The post I was responding to was about what would happen (specifically to arterials), theoretically, if suddenly we had 20% of commuters as cyclists; that's what my comment was built about.
And even with a left turn pocket, a cyclist will occupy the left lane for some period of time before reaching that left turn pocket... during that period, traffic will have to slow to the cyclists pace. And no, no hard braking is needed by motorists... even now... but they still have to slow down. That is exactly what happens now when a cyclist makes a left turn... only it happens so infrequently as to not be an issue...** try that with 10 or 20 times more cyclists on the road.
I don't agree, but I'm not really interested in arguing the point further. I have no evidence to back-up my assertion, it was simply idle musing based somewhat on experience. Disagree if you wish.
Originally Posted by
Bekologist
Left turning traffic causes significant traffic delays - and collisions - on roads, even multiple lane roads, without center turn lanes.
There are many many miles of two lane each direction, no center turn lane roads in the US.
True, but I believe the initial point I was responding to was about theoretical effect on arterials from 20% rider share. I think it's safe to say most of that 20% share would be in more urban environments, where traffic already moves fairly slow and arterials often have some sort of turn facilities (often for the very purpose of freeing up traffic).
And true, there are lots of roads without turn facilities - but the majority of what could be called arterials, both here in Fresno and in my experience a lot of California, has them. Couple that with the fact bikes are likely going to be in urban environments, and I'm not sure the effect on arterials would be that drastic. But, as I said, this is idle musing and I'm not really interested in pressing the matter.
Bike traffic taking an entire lane, moving 12 miles an hour, with limited opportunities to road share, would have a significant impact on ADT of most roads. hence some of the misguided efforts of some road crews to paint those shared lane arrows off to the side, contrary to MUTCD minimum standards.
Again, I disagree, but I have no evidence to back up my claims.