BARF - Bay Area Riders Forum

Go Back   BARF - Bay Area Riders Forum > Moto > 1Rider


Notices

Reply
 
Thread Tools Display Modes
Old 07-24-2019, 05:10 PM   #16
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
My "never get out of the boat" comment was mostly tongue-in-cheek. But still, the graph in post #9 showing San Francisco with 2.5 to 3 times as many motorcycle crashes as Oakland and San Jose was a real WTF revelation. To any San Franciscan thinking about taking up motorcycling, my recommendation would be, first, to move.

Quote:
Originally Posted by ThinkFast View Post
I recall seeing data from a few years ago that showed a high correlation between returning boomer riders, heavyweight bikes and alcohol-related fatalities and injuries. Did you look at alcohol-related crashes in your research? It's a pretty easy story to imagine: returning rider buys that heavyweight bike they've always dreamed about. Goes out with the buddies for a daytrip, and "just has one beer." And then on the way back - surprise surprise - discovers that even one beer can compromise your ability to keep a big heavy bike on the road. Hypothesis: as this demo ages out, we will see less of this particular relationship in the data.
I found just that in a project last year. The following graph is derived from NHTSA's Crash Report Sampling System and its predecessor, the General Estimates System. It is an estimate of US crash involvement based on a statistical sample of police accident reports. It is not from the Bay Area crash data I'm using in this thread.



This is what I wrote in a post elsewhere:
Note the three humps at 1990, 2000, and 2010. Dominant age groups are: in the first 25-34; in the second 35-44 and 45-54; and in the third 45-54 and 55+. What do these groups have in common? Their birth year is mid-1960s and earlier--it's the same group of riders seen over a 20-year span. Unlike that group, the 1970-1990 birth-year cohort--now ages 50 and under--has never been a big part of the alcohol involvement group. At present, these riders--the < 25, 25-34, and 35-44 age groups--are a small and declining segment of the drinking-and-riding-and-crashing group. An eyeball projection out 5 or 10 years suggests that the pre-1960 cohort will be nearly gone and the overall rate of alcohol involvement in motorcycle crashes will be down around 3%.
__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 09-27-2019 at 10:41 AM..
DataDan is offline   Reply With Quote
Old 07-24-2019, 06:06 PM   #17
Slow Goat
Fun Junkie
 
Slow Goat's Avatar
 

Join Date: May 2017
Location: Pleasant Hill
Motorcycles: Make me feel better about life...
Name: Bob
Great compilation, Dan. Always good to have more understanding of what the numbers really are.
Slow Goat is offline   Reply With Quote
Old 07-25-2019, 12:24 PM   #18
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Freeway crashes by freeway

I've slowed down due to temporary burnout from work on 2-vehicle city crashes. The next topic will be freeway crashes, probably next week. But this morning I amused myself counting freeway crashes by freeway. It seemed to make most sense segmented by county. This covers about one-third of segments with reported crashes and 70% of total freeway crashes.

Bay Area Motorcycle Crashes on Freeways 2013-2017

freeway..county...........crashes
I-880Alameda615
I-580Alameda543
US-101Santa Clara527
I-80Alameda361
US-101San Mateo313
I-80San Francisco274
SR-4Contra Costa268
US-101San Francisco246
I-280Santa Clara234
I-80Solano230
SR-85Santa Clara200
I-80Contra Costa192

There's some fuzziness built in because I relied strictly on roadway name and didn't precisely locate each crash. US-101 in San Francisco probably includes some crashes on Van Ness, which is 101 north of the Central Freeway. I think SR-4 is not officially a freeway in a few sections between Martinez and I-80, and is definitely not a freeway east of Brentwood.
__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 07-26-2019 at 03:55 PM.. Reason: corrected table values
DataDan is offline   Reply With Quote
Old 07-26-2019, 02:25 PM   #19
mobileninja
Newbie
 

Join Date: Jul 2019
Location: San Francisco
Motorcycles: 2006 SV650
Name:
Love this data - very interesting =)
Thanks for doing all the work.

San Francisco city riding is definitely a mixed bag. The combination of bad roads and impatient drivers means you have to be incredibly cautious about everything and everyone around you. You could be humming along between cars and find yourself heading straight for a huge pothole that is awkwardly shaped and need to figure out a way around it :|

Additionally, with the incredible boom of electric scooters and bicycles has actually made riding a motorcycle X-times harder. They weave in and out of the cars very fast and most of the time are not paying attention to other vehicles (me) coming down between the lanes. Especially downtown you have to be aware of all of them in all lanes at all times.

Riding in the city sucks =) I stick to larger main roads that move to fast for the scooters/bicycles any chance I can get.

Last edited by mobileninja; 07-26-2019 at 02:26 PM..
mobileninja is offline   Reply With Quote
Old 07-29-2019, 07:59 AM   #20
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Single-vehicle city street crashes

Twenty percent of Bay Area crashes in incorporated cities, but not on freeways, were single vehicle. In some, the motorcyclist lost control and grip, and the machine went down. In others, it hit a stationary object. This post will identify maneuvers that preceded these crashes and causes that contributed.

This graph shows the two kinds of crashes, going down and hitting something. Collision types "overturn" and "other" are combined because some agencies code the type of collision when a motorcycle overturns as "overturn" while others code them as "other", distinguishing them from car and truck overturns.




In 58% of the single-vehicle city crashes, the motorcycle was going straight, not turning, before the loss of control. It seems likely that these were crashes under braking, but the data does not provide that detail.




In 14% of all and 18% of overturns, the rider was not found at-fault. I suspect that other vehicles often contributed, perhaps by violating the motorcyclist's right of way, but were not involved in a collision and were not identified. Speed contributed to more than half. Improper turning, 13%, is a factor when the rider runs wide in a corner. DUI accounted for 8%.

__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 07-31-2019 at 09:58 AM.. Reason: slight mod to graph #2 for clarity
DataDan is offline   Reply With Quote
Old 07-29-2019, 11:41 AM   #21
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Two-vehicle freeway crashes

The 5700 Bay Area freeway crashes 2013-2017 were one-third of all police-reported motorcycle crashes in the region. Of those, 20% were single vehicle (the subject of an upcoming post), 60% were 2-vehicle (the subject of this post), and 20% were 3+ vehicle (no post since the crashes are much harder to evaluate). While I refer to the other vehicles involved in these crashes as "cars", they comprise every kind vehicle on the road: cars, SUVs, vans, trucks, buses, etc. However, I have not included bike-vs-bike crashes.

Fault in two-vehicle freeway crashes was nearly equally divided between the driver (51%) and the rider (49%).




Half of crashes were sideswipes, usually caused by the car. Close to 40% were rear-end, usually caused by the motorcycle. The remainder was distributed among several different categories.




This graph shows the pre-crash movement by the party at fault. When the motorcycle was at fault, it was going straight 68% of the time. When the car was at fault, it was changing lanes 85% of the time.




Finally, here are the primary factors behind the at-fault assessment. When the motorcycle was at fault, it was due to unsafe speed 70% of the time. For the car, it was an unsafe lane change 85% of the time

__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt
DataDan is offline   Reply With Quote
Old 07-30-2019, 09:25 AM   #22
GAJ
Veteran
 
GAJ's Avatar
 

Join Date: Mar 2008
Location: SANTA ROSA
Motorcycles: DRZ400SM, F800ST
Name: Geoff
Quote:
Originally Posted by DataDan View Post
Finally, here are the primary factors behind the at-fault assessment. When the motorcycle was at fault, it was due to unsafe speed 70% of the time. For the car, it was an unsafe lane change 85% of the time
Great stuff Dan.

I used to love lane splitting when I commuted before I retired.

But in a car watching some of these guys split at large deltas with traffic despite big gaps on both sides of them makes my skin crawl.

Same for excessive speed within urban environments.
GAJ is offline   Reply With Quote
Old 07-31-2019, 06:51 AM   #23
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Single-vehicle freeway crashes

Of 5700 motorcycle crashes on Bay Area freeways 2013-2017, 1100 or 19% were single-vehicle, a proportion similar to city-street crashes.

As with single-vehicle city-street crashes (see post #20), single-vehicle freeway crashes were usually overturns--68% freeway vs. 61% city. Most of the remainder in both was hitting a stationary object. The cause of the overturns was likely the same as on city streets--overbraking--though, again, that detail is not in the data.




In 49% of the single-vehicle crashes, the motorcycle was going straight before the crash, and in 35% it had left the freeway travel lanes.




The distribution of primary factors is similar in overturns and object strikes. For all single-vehicle freeway crashes, 42% were due to unsafe speed, 37% to improper turning. "Improper turning" in the freeway context appears to be a maneuver that ended in failure to stay in the travel lanes, causing the motorcycle to go down or hit something on the shoulder.

__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 09-27-2019 at 10:43 AM..
DataDan is offline   Reply With Quote
Old 07-31-2019, 10:48 AM   #24
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Single-vehicle rural crashes

With crashes on freeways and city streets covered in previous posts, one last location category remains, which I call "rural", comprising non-freeways in unincorporated areas. While many of these were on our favorite back roads, others were in unincorporated communities in urban areas. For example, Castro Valley, with population over 60,000, is in this group. Unfortunately, to separate the unincorporated urbans from the back roads would have required going through 3000 crashes one by one, since there is no data element to characterize them.

While freeway and city street crashes were about 20% single-vehicle, 45% of rural collisions were single-vehicle, the subject of this post. Of 1358 single-vehicle crashes, 65% were overturns, proportionally similar to single-vehicle city and freeway crashes.




In 43% of single-vehicle rural crashes, the motorcycle was going straight before the overturn or collision; in 52%, it was turning or ran off the road. As might be expected, it ran off the road much more often in rural crashes, 28%, than in city crashes, 5%.




The causes of single-vehicle rural crashes were improper turning, 47%, unsafe speed, 37%, and DUI, 8%.

__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 07-31-2019 at 10:50 AM..
DataDan is offline   Reply With Quote
Old 08-01-2019, 12:58 PM   #25
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Two-vehicle rural crashes

As discussed in my previous post, the "rural" category includes many different kinds of roads. Some are back roads, some are basically urban but in unincorporated communities (e.g., Castro Valley), and some are more like freeways (Highway 17 and parts of Lawrence, Montague, and San Tomas Expressways). Correspondingly, crashes were varied, too. Some were the expected twisty road crashes, but others were more like city street and freeway crashes. It is an unfortunately artificial grouping that doesn't really tell us much about crashes in a particular environment.


Two-vehicle rural crashes were only somewhat more common than single-vehicle, 55-45%, compared to 80-20% for city and freeway. At-fault division differed, too: The motorcyclist was at fault slightly more often than driver in two-vehicle rural crashes, 51-49%, while it was usually the driver on the freeway, 49-51%, and in the city 37-63%.




Crash types reflected the different environments included in the category. Broadsides (31%) were the most common, as they were in the city. Sideswipes (27%) and rear ends (21%) occurred in relatively high proportions, as they did on both city streets and freeways. Overturns (10%) and head-ons (8%) would seem to be more closely associated with loss of control in a curve.




When the motorcycle was at-fault in rural crashes, it was going straight before the crash in 50% of cases. But at-fault pre-crash movement also included passing (15%) and crossing the centerline (14%), actions more typical of crashes resulting from loss of control in a curve. When the car was at fault, it was turning left or changing lanes in 49%.




When the motorcycle was at fault, it was due to unsafe speed 44%, a common factor in all environments. Other factors that appeared frequently were wrong side of road (18%), improper passing (13%), and improper turn (8%). These would seem to be twisty-road errors. Primary factors when the car was at fault, however, were more typical of city street and freeway crashes: right of way violation (41%) and unsafe lane change (22%)

__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 08-01-2019 at 08:44 PM..
DataDan is offline   Reply With Quote
Old 08-04-2019, 07:57 PM   #26
pobey
Rookie
 
pobey's Avatar
 

Join Date: May 2016
Location: Vallejo
Motorcycles: Zero Sr/s Premium
Name: Dan
Thank You Dan for posting this useful information. I'm always processing such information for my publications. Thanks again from another Dan.
pobey is offline   Reply With Quote
Old 08-05-2019, 12:41 PM   #27
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Crash Fatalities

Earlier posts in this thread have been about all Bay Area motorcycle crashes reported to police, non-injury to fatal, derived from the CHP-maintained database of collisions reported by all agencies. For the next few posts, I turn to fatal Bay Area crashes that appear in the US DOT's database of US traffic deaths since 1975, which has considerably more detail than the larger CHP database.


We've come a long way in 40 years. Though the number of registered motorcycles statewide (I have Bay Area registrations only for the past 15 years) is 25% higher now than in the late 1970s, annual California motorcyclist deaths have fallen by 40%. The Bay Area drop was even greater at 60%.



The age distribution reveals another significant change. In 1978 and 1979, 90% of deaths were of riders under age 35, annual deaths under age 25 averaged 105, and 55 teenagers were killed per year. Now, the < 35 group is less than half, only 104 under age 25 have been killed in the past TEN years, and in the past five years, 5 teenagers died in total.

The tragic loss of young lives would not be tolerated today, and it was not tolerated for long back then. In the 1980s, the horrific death toll drove two legislative efforts: The training requirement first for riders under 18 (1987) then under 21 (1991), and the all-rider helmet law (1992).
__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 08-05-2019 at 02:09 PM..
DataDan is offline   Reply With Quote
Old 08-11-2019, 07:27 AM   #28
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Fatal crashes by location

After the short detour into history, back to crashes 2013-2017. First, an overview.

Bay Area Fatal Motorcycle Crashes 2013-2017

fatal motorcycle crashes...332
motorcycles involved.......343
riders killed..............319
passengers killed..........8
non-motorists killed.......7

Non-motorists were 7 pedestrians and 1 bicyclist. More on that in a later post.


Distribution of fatal crashes by county is somewhat different than the distribution of all crashes seen in post #1. While Alameda County had more total crashes than Santa Clara, the Santa Clara crashes were more likely to be deadly. OTOH, San Francisco's crashes were much less likely to be deadly--dropping from third on list of all crashes to a distant seventh in fatal crashes.




Post #9 showed the extraordinary number of crashes in San Francisco. But they were less likely to be deadly than those in other cities.




In post #6, crashes of all severities were broken down by roadway type: non-freeway crashes within city limits, freeway crashes, and "rural" or non-freeway crashes outside of city limits. This is the same data in a slightly different graph.




Fatalities were distributed somewhat differently than non-fatal crashes.




The crash and fatality distributions make it possible to calculate crash lethality, the percentage of crashes that claimed lives, by roadway type. While city crashes were close to the average Bay Area lethality of 2.0% (see post #1), freeway crashes were less likely than average to be deadly, and rural crashes more likely.

__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt
DataDan is offline   Reply With Quote
Old 08-11-2019, 08:10 PM   #29
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Vehicles involved

The NHTSA fatal crash data includes VIN (first 12 characters), and an auxiliary file with make/model details is provided. In this post I will show the make, model, and style of the motorcycles in fatal Bay Area crashes and style of the other vehicles in those crashes.


Motorcycles in Fatal Bay Area Crashes by Style 2013-2017

sport14943%
cruiser8926%
touring3510%
traditional196%
enduro196%
dirt103%
scooter82%
other/unknown144%
total343 

"Style" is provided by R.L. Polk, an auto industry information service. The first three are pretty much what you would expect, but "touring" is loaded with Harleys, 22 of them. "Traditional" is what we used to call "standard"--unfaired, no cruiser styling cues. "Enduro" was probably a good description at one time, but it is now adventure and dual-sport. For "dirt" I combined street-legal dirtbikes and motocrossers (in road accidents). "Scooters" are what you would recognize as scooters.


Motorcycles in Fatal Bay Area Crashes by Make and Model 2013-2017

makemodelcount%
BMW 113%
 S 1000 RR5 
Ducati 113%
Harley-Davidson 9728%
 FL56 
 FX21 
 Sportster15 
Honda 4212%
 CBR600 RR10 
 CBR1000 RR6 
Kawasaki 3510%
 EX250/3007 
 EX500/6506 
 ZX600/6367 
 ZX10004 
KTM 41%
Suzuki 5115%
 SV/SFV6505 
 GSX-R60012 
 GSX-R7505 
 GSX-R10007 
Triumph 93%
Yamaha 6619%
 YZFR620 
 YZFR112 
 XVS9504 
other/unknown 175%
total 343 

I didn't include all makes in this list, excluding the ones and twos. Count on the make line is the total for the make. I broke out some model counts that might be of interest. Many different Harley models appear, but I don't know much about 'em except the two basic kinds of Big Twins and Sportsters. I was surprised how few Japanese cruisers appear in the data, and only one numerous enough to make this list.


Other Vehicles in Fatal Bay Area Motorcycle Crashes by Type 2013-2017

car9938%
SUV6023%
pickup3413%
minivan176%
other light truck62%
med/lrg straight truck156%
tractor-trailer156%
other/unknown187%
total264 

I didn't find much of interest in the make/model distribution so didn't include it (but will on request). For info, there were as many Priuses as Peterbilts--5 each.
__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt

Last edited by DataDan; 08-12-2019 at 06:31 AM..
DataDan is offline   Reply With Quote
Old 08-12-2019, 03:08 PM   #30
DataDan
Mama says he's bona fide
 
DataDan's Avatar
 
BARF Mod Alumni
BARFie winner 2010 & 2014
Contributor ++++

Join Date: Feb 2003
Location: San Luis Obispo
Motorcycles: Yamaha FJR1300
Name: Dan
Types of Fatal Crashes

Earlier in the thread, I covered types of crashes for all severities, non-injury to fatal, from the CHP database. For fatal crashes only, the NHTSA database includes more detail on the events of a crash, the subject of this post.


In Bay Area fatal motorcycle crashes 2013-2017, the motorcyclist was at fault in 75% of all cases and 62% of multiple-vehicle crashes. These percentages are higher than for all-severity crashes, 54% for all and 42% for multiple-vehicle.

In 73% of single-vehicle fatalities, the motorcycle ran off the road. In 14% it struck an object, and in 11%, the bike overturned. The assessment of these factors is made by NHTSA after examining the police crash report. One or more may occur--ran off the road, overturned, hit object--but the factor cited is the one judged to be the initial event of the incident.




Multiple-vehicle fatalities comprised many different kinds of crashes, as shown below. A collision with a left-turner, either oncoming or from the right, was the most common, 28%. This was also the most common non-fatal crash on city streets. Rear-enders, motorcycle striking, was the second most frequent fatal crash at 14%. These occur both on city streets and freeways. Sideswipes in the same direction of travel were the highest non-fatal freeway crash and third among fatalities.

__________________
How can I help seeing what is in front of my eyes? Two and two are four.
--Winston Smith

I see four lights!
--Jean Luc Picard

A is A.
--John Galt
DataDan is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -8. The time now is 11:47 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.