Not to spoil the interesting back-and-forth, but since none of the local guys have chimed in I will.
This is part of Mulholland, a famous road for motorcylces and high-performance cars (and the "home stretch" for the folks who live up in the Santa Monica Mountains / Malibu Canyon area).
To put all of these crashes in that first video in perspective for you guys:
In the greater Los Angeles area, there are two "main" areas where all the motorbike riders seem to flock to. The first is Angeles Crest Highway, which runs in the San Gabriel mountains which are the east-west running mountains that form the northern border of the Los Angeles basin. ACH or Highway 2 as it is known, has a famous cafe way up in the mountains up there called Newcomb's Ranch, and on any given sunny day you'll see plenty of bikes up there, even on a random weekday (providing it's relatively warm and no snow/ice up there). On the weekends it's pretty insane especially during the summers. I'll see if I can locate a picture. I've seen a hundred bikes or more, easily, on a warm summer afternoon up there, and there are always at least as many bikes out running around on the various roads.
The other area is the Santa Monica Mountains and Malibu Canyon, including Mulholland which is where this video was filmed. I got my first canyon riding experience here because it is slightly closer to where we live as opposed to having to slog through the central Los Angeles traffic on my way to and from ACH. The famous motorcycle hangout up there is called The Rock Store and for whatever reason, it tends to attract a lot of the weekend warrior/douchey types, both of the cruiser/Harley crowd as well as the sporting crowd.
And, of course, like any canyon roads close to a major city, there are always the guys who are going to go out there and absolutely flog it - to hell with speed limits or consideration for others' safety (a-la-the Corvette crossing the double line, etc.).
Regarding the specific corner where you see all of these crashes, in my experience there are a few factors at play that you wouldn't know from looking at the video:
1) That corner is actually the last turn in a long succession of a section of road that is referred to locally as "The Snake" (See my attached image). People (I think) tend to think of it as "the grand finale" of the Snake and try to put a bit of flourish on it. Some people may be tired from the previous stretch which can be scary if you're not familiar with the road, and this can get people's heads out of the game for this big corner.
2) The majority of the crashes you see on the Snake are in that corner, right after people who have been traveling uphill through the Snake have come through some very technical turns, the last few of which are under trees and therefore shaded. I mention this only because from a sensory perspective, suddenly it's brighter than it was a few moments ago, and you have a little road to run on and gain speed going into that turn.
3) As you approach this turn (again going the uphill direction), you see what appears to be a wide-open, lefthand sweeping uphill turn. Some people get overanxious to get on the gas here; some people target fixate halfway through the turn. Other run it a tiny bit wide and instead of turning harder, stand it up and go into the dirt, while others overturn, hit that painted double yellow line and wash out the front tire. Other simply hit the brakes and tuck the front, or get on the gas too early/too aggressively.
4) This cannot be overstated enough - it is VERY well known locally that on any given day a) there are likely to be a crowd of people uphill from that spot (which you can see in the very last shot in the video, where the guy has a wobble and saves it) watching and frankly waiting for a spill, and b) the photographers will be up there. These things may contribute to some people getting self-conscious not keeping their wits about themselves, resulting in a small error which turns into a crash.
For my money, I like to ride everywhere *but* The Snake due to all the yahoos in cars and on bikes going way too fast, the sheer volume of yahoos, the dangerous nature of the road in terms of being able to predict (without a lot of local knowledge) the "sharpness" of the curves and camber (blind curves in other words), road debris which is very common up there (gravel from tiny rockslides mainly), and slow-moving traffic and the occasional animal/roadkill in the road. I have personally witnessed crashes just like you see in that video, in that turn.
See the image I've attached below. I've put a red box in the lower left hand part of the image, around the corner where the video is filmed. I've indicated the direction that the vast majority of those folks were traveling - uphill/West. I've also indicated where The Rock Store is located - where a lot of these guys who crashed were 10 minutes ago, telling each other testosterone-fuelled bullsh*t stories about how badass/fast/fearless they are. After they pick up the pieces and head back down, they will blame their equipment or debris or pretty much anything except rider error for their wreck.
https://goo.gl/maps/DrxJK
Please note: I am not a "speed limit/buzzkill" type of rider - though I generally attempt to adhere to the speed limit (and virtually always do in unfamilar territory) - I like to ride "fast" and have fun. But, I also have a STRONG AVERSION TO CRASHING and certainly to injury, hence my approach to riding - have fun, feel those turns, but live to ride another day.
Have fun/ride safe!
-Mark
p.s. here's a Google Map link to where we're talking about:
https://goo.gl/maps/DrxJK
