[net.cycle] Screeeech.....

jdi@ingres.ARPA (John D. Irwin) (12/04/85)

I've owned an 82 Yamaha Vision for six months, and am very happy with it,
except for a few small problems.  Actually the big problem isn't really a
problem at all, in the sense that the bike meets spec.

---  WARNING -- Reader's digest type story follows :-)  ---

So anyway, I was driving down highway 101, about 15 miles south of San Fran-
cisco doing about 50mph in the fast lane.  Traffic was medium (cars closely
spaced).

Rule #1:  Do not, NOT, NOT follow cars as closely as cars follow cars.

Getting back to the story, the person in front of me decided to play
"Death Race 2000" on the highway.  He hit his brakes so hard I saw the
tires loose traction.  So anyway, here I am barrelling towards this maniac
and NO-WAY am I going to be able to stop short of hitting him.  So I give
it a try anyway (I mean, what else is there to do? :-) and actually end up
going only about 10mph when I hit him.  Well, that was enough to cause me
to start to lose control of the bike, but it didn't really matter because the
person behind me hit me anyway.  (Which was probably a good thing, because she
stopped a LOT quicker than the person BEHIND her, who smashed her radiator
and the rear end of the car behind me very well).  Oh, the person who tried to
kill me didn't stop to see if he succeeded.

It's a very interesting feeling lying on a superslab thinking "Gee, I'm not
dead!"  (I was wearing my helmet, of course, but you probably know how much
that helps your mood when you see a crash coming only seconds away)

--- End of story ---

Getting back to the point, I wondered if anyone else out there who has a Vision
has (heard of/actually done) adding another disc brake to the front wheel.
This was done in the 83 Vision, which tells me it's probably a pretty good
idea.  But if it's going to cost me a whole new brake system...



Oh, one more thing.  The car that hit me from behind was a rental, so the
rental company is supposedly responsible for the damage their car did to my
bike (which was pretty considerable, but fortunately almost nothing down
in the 'guts' was hurt).  However, when I call them they all reply in the
'huh?' tone I'm sure you've all heard.  "Oh, gee, I think I'm supposed to
transfer you to Mr. XXX, please hold on................................"
Is there a fast way to make them notice me, or am I going to have to get a
lawyer and threaten to sue?

--
John D. Irwin
jdi%ingres@ucbvax.UNIVERSE

david@tekig5.UUCP (David Hayes) (12/05/85)

Dear John,



	Actually, the single disk on your Vision should have been
able to lock up the front wheel in a panic situation.  If adjusted
properly, and assuming things weren't wet, your bike should be
able to outstop almost every car on the road.  I think tests show
around 130 ft. from 60 mph.  The three variables that got you here
were following to closely, although if a car can get stopped, so should
a bike. No. 2 is your ability to extract near 100% stopping power
from your bike, very hard without practice. No. 3, a front tire
as good as OEM.  Granted,  haven't practiced panic stops myself, so
I'd probably be picking myself out of someones tail light too.

One other choice is to brake heavily, then try and miss the car in
front to one side or the other.  Since you were in the fast lane,
I would have tried for the guard rail side, again not too easy
with a nice chrome bumper rapidly approaching your adams apple.

Remember, it is always better to brake hard than to lay it over,
since a sliding bike me develop around .3-.4 G's and up on the 
tires it can approach 1 G of stopping force.  If you liken 
yourself to James Bond you are allowed to slide UNDER those
high trucks.

dave

levy@ttrdc.UUCP (Daniel R. Levy) (12/07/85)

In article <355@tekig5.UUCP>, david@tekig5.UUCP (David Hayes) writes:
>
>One other choice is to brake heavily, then try and miss the car in
>front to one side or the other.  Since you were in the fast lane,
>I would have tried for the guard rail side, again not too easy
>with a nice chrome bumper rapidly approaching your adams apple.
>
>Remember, it is always better to brake hard than to lay it over,
>since a sliding bike me develop around .3-.4 G's and up on the
>tires it can approach 1 G of stopping force.  If you liken
>yourself to James Bond you are allowed to slide UNDER those
>high trucks.
>
>dave

Envision the 'James Bond' biker falling to the pavement under a high
truck (after bumping his head on a downward-poking part of the under-
structure) and **CRUNCH** go the rear steamrollers (er, wheels).  Gorey.
-- 
 -------------------------------    Disclaimer:  The views contained herein are
|       dan levy | yvel nad      |  my own and are not at all those of my em-
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| at&t computer systems division |  upon which I may hack.
|        skokie, illinois        |
 --------------------------------   Path: ..!ihnp4!ttrdc!levy

marauder@fluke.UUCP (Bill Landsborough) (12/09/85)

In article <355@tekig5.UUCP> david@tekig5Hayes.UUCP (David Hayes) writes:
>Dear John,
>One other choice is to brake heavily, then try and miss the car in
>front to one side or the other.  Since you were in the fast lane,
>I would have tried for the guard rail side, again not too easy
>with a nice chrome bumper rapidly approaching your adams apple.
>
>Remember, it is always better to brake hard than to lay it over,
>since a sliding bike me develop around .3-.4 G's and up on the 
>tires it can approach 1 G of stopping force.  If you liken 
>yourself to James Bond you are allowed to slide UNDER those
>high trucks.
>
>dave


I agree with you dave about its better to brake hard than to lay it
over because in the old days men use to say, " I saw that I was goin'
to hit the barrier so I 'laid it down.'"  Thats real dumb because
crash bars or aluminum cases on pavement make excellent slide rails
and the bike will never stop. (By the way, crash bars have been
outlawed in some states for this reason).

What usually happens to cause a rider faced with a collision is the
rider panics and grabs a death grip on the front brake, locks the
wheel and at the same time tries to turn to avoid the collision.  The
result is the bike goes down and both the rider and bike go under the
car (or whatever).

I would recommend riders first learn to ALWAYS use the front brake,
even with the simple, no panic stops.  That way it becomes very
automatic to always use it and therefore automatic in an emergency.
Also everyone should practice quick stops in an empty school parking lot
or somewhere there is good pavement and no cars.  Once you have
learned what your brakes are capable of you are much better prepared
for the surprises. 

Bill Landsborough
----

"Love is patient and kind; love is not jealous or boastful; it is not 
arrogant or rude... Love bears all things, believes all things, hopes all
things, endures all things."   1 Corinthians 13:4-7

animal@ihlpa.UUCP (D. Starr) (12/10/85)

While discussing the phenomenon of "laying it down," Bill Landsborough
remarked that:
> What usually happens to cause a rider faced with a collision is the
> rider panics and grabs a death grip on the front brake, locks the
> wheel and at the same time tries to turn to avoid the collision.  The
> result is the bike goes down and both the rider and bike go under the
> car (or whatever).
> 
This is not quite true.  According to Harry Hurt's study of motorcycle
accidents, in the vast majority of collisions the front brake is never
touched.  Instead, the car-driver reflex (stomp the right foot on the
brake) comes into play and the rear end slides out, putting the bike on
its side.  With the combination of modern front tires and the weight
transfer effects typical of motorcycles, it is rather difficult to lock
up the front wheel on dry pavement (if you don't believe me, try it some
time).  Regardless of the above nit-pick, the advice to use the front
brake as the normal method of stopping is still sound.

As an aside, I wonder if the idea of "laying it down" originally evolved
in the days before paved roads.  On loose gravel or dirt, a motorcycle
may very well stop more quickly on its side.  More likely, I suspect, is
that "I laid it down" sounds better than "I fell over."

Another nit-pick:

> ...crash bars or aluminum cases on pavement make excellent slide rails
> and the bike will never stop. (By the way, crash bars have been
> outlawed in some states for this reason).
> 
Outlawing crashbars <another aside:  did you know that only one motorcycle
manufacturer (BMW) actually calls the things CRASH bars?  The others use
less frightening language like safety bars, case protectors, dresser bars,
etc.> makes little sense.  They don't hurt anything if you stay upright,
and if you fall over they will at least keep your leg from getting stuck
under the bike, and reduce the engine damage somewhat.  Are you sure that
some states have outlawed them--the only regulations concerning crashbars
that I know of is that Arkansas *requires* them on 750cc or larger bikes
(although the law is not enforced in my experience).

	Dan Starr

"Wash your bike regularly; the salt season is upon us!"

marauder@fluke.UUCP (Bill Landsborough) (12/12/85)

In article <924@ihlpa.UUCP> animal@ihlpa.UUCP (D. Starr) writes:
>While discussing the phenomenon of "laying it down," Bill Landsborough
>remarked that:
>> What usually happens to cause a rider faced with a collision is the
>> rider panics and grabs a death grip on the front brake, locks the
>> wheel and at the same time tries to turn to avoid the collision.  The
>> result is the bike goes down and both the rider and bike go under the
>> car (or whatever).
>> 
>This is not quite true.  According to Harry Hurt's study of motorcycle
>accidents, in the vast majority of collisions the front brake is never
>touched.  Instead, the car-driver reflex (stomp the right foot on the
>brake) comes into play and the rear end slides out, putting the bike on
>its side.  With the combination of modern front tires and the weight
>transfer effects typical of motorcycles, it is rather difficult to lock
>up the front wheel on dry pavement (if you don't believe me, try it some
>time).  Regardless of the above nit-pick, the advice to use the front
>brake as the normal method of stopping is still sound.
>
Dan, you are right about the Hurt report.  Most riders do not touch
the front brake.  However the ones who use it "just for emergencies"
do what I described above.  And it is quite easy to lock your front
brake with most motorcycles on dry pavement, especially when you turn
the front wheel sideways!  We use to play a game in the Bay Area  as
to who could lock their front brake the longest on pavement and still 
keep going.  Believe me it is quite easy on most bikes. (I ride a
Kawasaki GPZ 1100 with Dunlop Sport Elite tires)

>Another nit-pick:
>
>> ...crash bars or aluminum cases on pavement make excellent slide rails
>> and the bike will never stop. (By the way, crash bars have been
>> outlawed in some states for this reason).
  
>They don't hurt anything if you stay upright,
>and if you fall over they will at least keep your leg from getting stuck
>under the bike, and reduce the engine damage somewhat.  Are you sure that
>some states have outlawed them--the only regulations concerning crashbars
>that I know of is that Arkansas *requires* them on 750cc or larger bikes
>(although the law is not enforced in my experience).
>
>	Dan Starr

I read in I think Cycle Guide magazine that Mississippi does not allow
crash bars.  I don't necessarily agree with their reasoning but I can
believe that it is true.

Bill Landsborough

dave@rocksvax.FUN (Dave Sewhuk) (12/17/85)

/* rocksvax:net.cycle / marauder@fluke.UUCP (Bill Landsborough) / 11:11 am  Dec 12, 1985 */
>Another nit-pick:
>
>> ...crash bars or aluminum cases on pavement make excellent slide rails
>> and the bike will never stop. (By the way, crash bars have been
>> outlawed in some states for this reason).
  
>I read in I think Cycle Guide magazine that Mississippi does not allow
>crash bars.  I don't necessarily agree with their reasoning but I can
/* ---------- */
I would hope they are not outlawed because a bunch of studies in Japan
and the National Traffic Safety board conclude that they help reduce
injuries significantly when a side collision occurs, like the bimbo that
ran into me.  Mr. Harley got a patent in 1938 on them.  I have to dig out
the stuff my lawyer sent me, but the data from from some of those
studies seemed pretty convincing that they help.  They not only
help prevent engine/bike damage, but it significantly reduces the damage
that can occur to the leg that gets between the bike and the other vehicle.
I am conviced I wouldn't have spent 7 months recovering from a smashed
up leg if my bike had them!!

I can't believe that crash bars will cause you to slide any further anyways.
Without them the side of your engine get scraped down, with side bars
they get scraped down by the asphalt.  Besides without them part of what
gets scraped is your leg!!  The equivalent 'braking' surface can't be
all that much different. If the engine dug into the road that hard I would
think that there would be a tendency to roll the whole works over.
Besides I would rather loose that kinetic energy slowly than suddenly!!

Dave

arpa: Sewhuk.HENR@Xerox.ARPA
uucp: {ihnp4,rochester,amd,sunybcs}!rocksvax!dave
ns: "Sewhuk:HENR801C:Xerox".ns@Xerox.ARPA

bob@pedsgd.UUCP (Robert A. Weiler) (12/19/85)

Organization : CONCURRENT Computer Corp, Tinton Falls NJ
Keywords: 

In article <620002@rocksvax.FUN> dave@rocksvax.FUN (Dave Sewhuk) writes:
>
>I can't believe that crash bars will cause you to slide any further anyways.
>Without them the side of your engine get scraped down, with side bars
>they get scraped down by the asphalt.  Besides without them part of what
>gets scraped is your leg!!  The equivalent 'braking' surface can't be
>all that much different. If the engine dug into the road that hard I would
>think that there would be a tendency to roll the whole works over.
>Besides I would rather loose that kinetic energy slowly than suddenly!!
>
>Dave
>
>arpa: Sewhuk.HENR@Xerox.ARPA
>uucp: {ihnp4,rochester,amd,sunybcs}!rocksvax!dave
>ns: "Sewhuk:HENR801C:Xerox".ns@Xerox.ARPA

As a side note, why not rubber coat or attach outward facing rubber
plates to the crash bars? This should make them a better braking
surface than the engine cases. I have never seen crash bars so
constructed. Has anybody seen anything like it?

Bob Weiler