Frequently
Asked Questions
Will
I like this product?
How
safe is Isaac®?
Does
Isaac® meet SFI 38.1 performance levels?
How fast can I go and still be protected?
Why doesn't the performance chart show a range of loads
for Isaac®?
What about lateral (side) loads?
Why use shock absorbers?
How much can I move my head?
Do I have to send you my helmet?
How difficult is it to attach the helmet mounts to
the helmet?
Is the helmet weakened after drilling holes in it?
Will the angle of my car's seat make a difference?
Why
don't you put the crash video on your web site?
Why are these products so expensive, even the "cheap"
ones?
Where did the name "Isaac" come from?
Will
I like this product?
No. It's like buying insurance, you won't like it until you need
it. You will spend hard-earned money, spend time installing the helmet
mounts and have to futz with connections when you get in your car. Then
one day, when you least expect it, things will go very wrong and for about
50 milliseconds you will be proud of your purchase. Of course, you will
be too panicked at the time to realize this. You may wake up in a hospital
bed complaining about one thing or another. That's our objective: Racers
who are around to complain. It's part of the service. (Go
to top)
How
safe is Isaac®?
Isaac® has never been beaten in a crash test.
Never. Isaac is as safe as any product you can buy; safer if other products
are worn loosely. And because it isn't worn, it can't trap you in a burning
car by getting snagged on something. When we crash tested in July 2002,
we were the best product ever tested, reducing head loads from about 1,800
pounds (8.0kN) for an unprotected driver to just 225 pounds (1.0kN). A
few weeks later other products were tested with little slack and matched
our numbers. The important thing to remember is that the better products,
like Isaac®, have succeeded in removing nearly 90% of the head loads.
(Go to top)
Does
Isaac® meet SFI 38.1 performance levels?
Yes, Isaac® outperforms all other products in SFI testing.
However, it is not "SFI certified". For more information
on this subject, click here. (Go
to top)
How
fast can I go and still be protected?
It's not how fast you go, it's how fast you stop. Head loads are created
by the "G" force of deceleration in the driver's compartment.
The crash test is run at only 35mph, but the steel sled, with no "crumple
zone", stops in about 12 inches (30cm). The next time you are driving
on the street at that speed, imagine stopping that fast. That's you
stopping that fast, not your front bumper. This impact creates a load
on the upper neck that is twice the lethal limit. (Go to
top)
Why
doesn't the performance chart show a range of loads for Isaac®?
Because Isaac® is not adjustable and does not need to be kept tight.
It works the same way every time. Classic "head restraints"
work based on position. The tighter they are, the better they work. (Go
to top)
What
about lateral (side) impacts?
Standard lateral impact tests have not yet been developed for racing,
but they are in the works. Computer simulations indicate that Isaac®
will reduce head loads caused by lateral impacts by 50%. This makes sense.
Isaac® should offer some lateral support because one shock will
be in tension and the other in compression. Tether-based "head restraints"
only work in tension — you can't push on a rope. (Go
to top)
Racers
who use Isaac® tell us that it stabilizes the head when cornering,
especially on rough tracks. These are casual observations from racers,
however, not scientific tests. (Click here
for Racers' Comments.) (Go to top)
Why
use shock absorbers?
Shock absorbers
work based on velocity, not position. The higher the velocity the stiffer
they get. When do you have high head velocity? When you crash. The shocks
don't care where your head is when you crash, they are just along for
the ride. But when you crash they become almost solid. (Go
to top)
How
much can I move my head?
Anytime you connect something to your helmet you will lose some mobility.
Mobility with Isaac® occurs in two stages. The first is the natural
movement of the mechanical connections and the rollers on the belt. This
is
adequate for most racing — checking mirrors and flag stations —
and is equal to, or better than, what you would get with other products
that are tightened enough to perform as well as Isaac®. The second
stage is extra head movement that requires compressing or extending the
shocks. This is annoying at first, but is easy to get used to. With the
motor off, you can actually hear the damping fluid moving through the
shock valve. (Click
here for Racers' Comments.)
Summary:
If you have never used a head and neck system before you won't like it,
or any other product for that matter. If you have, you will. (Go
to top)
Do
I have to send you my helmet?
No, please don't. We do not know how long your neck is, how big your neck
is, how big your shoulders are, where your belts ride on your shoulders,
how your seat is shaped or the angle of your seat. Besides, Isaac®
doesn't care since it doesn't really touch the body. That's why there
aren't different sizes. You may as well install the mounts youself, and
save the time and expense of round-trip shipping. (Go to
top)
How
difficult is it to attach the helmet mounts to the helmet?
If you have worked with helmets before it is pretty simple. If you have
not, you will need more patience than effort. All mounting hardware is
included, and the instructions are straight forward. All racers are good
mechanics, so give yourself about an hour or two. Look on the bright side:
You only have to do it once.
The adhesive mounting kit we offer is easier and faster than using nuts
and bolts. It takes about an hour to install the mounts, and you don't
have to check them periodically to make sure they are tight. The only
disadvantage is that you must wait 12 hours for the adhesive to cure.
(Go to top)
Is
the helmet weakened after drilling holes in it?
No. In all of our crash tests we used the cheapest, full-face helmet we
could find — fiberglass, not Kevlar®
— just to see if it would survive. For our first test we purposely
used a weak connection on one side and a strong connection on the other.
The weak connection ripped out of the fiberglass shell and all
of the load (nearly one ton) went to the other connection, which did not
break. We then used the same helmet, with strong connections,
in the next test. Not only did it hold up, we couldn't even find any cracks.
(Go to top)
Will
the angle of my car's seat make a difference?
No. Isaac®can be used with any racing seat provided it has normal,
three-inch wide belts. A more reclined angle allows more body motion forward,
regardless of the head and neck product you use, but does not alter the
general range of head and neck loads.
Also,
it works great with an office chair! Just attach some belts to the chair
and jump in with your helmet and Isaac® for some great holiday party
fun. And if you're the competitive type (what racer isn't?), slap an accelerometer
on that bad boy and see how many Gs you can generate!
(Remember,
don't drink and drive.) (Go to top)
Why
don't you put the crash videos on your web site?
We were going to put the videos on the web site until a racer
said, "If my wife sees that, she'll make me stop racing." Racing
is supposed to be fun. Trust us, you don't want to see them. (Go
to top)
Why
are these products so expensive, even the "cheap" ones?
Volume. Until they are required items, like harnesses and helmets, they
will remain expensive.
Development
costs are very high, especially for Isaac® since nobody knew how
stiff the shocks had to be. We ran many computer simulations and several
crash tests before we finally tuned the stiffness, something called the
damping coefficient. To put this in perspective, the license fee for the
computer simulation software alone is $25,000 per year. And don't ask
what crash testing costs. Of course, that doesn't include the cost of
researching the subject, engineering the prototypes, building the prototypes,
travel, patent lawyers who make sure we don't step on anyone's toes, etc.
Spreading that expense over a small volume is a painful exercise in accounting.
While
developing and manufacturing Isaac® is expensive, we are able to
keep costs reasonable by not having to carry various sizes, not needing
technicians who wait around for your helmet to show up, and selling it
directly to you. You are paying for the research and the physical product
only. (Go to top)
Where
did the name "Isaac" come from?
Yes, the product is named after some guy who has been dead for 276 years:
Sir Isaac Newton, considered by many to be the greatest scientific mind
in human history.
From
the very beginning we wanted to develop a system that would offset the
head loads that occured during rapid deceleration. In a perfect world
this would be an "equal and opposite reaction," Newton's Third
Law of Motion. The force on the head comes from the expression, "Force
equals mass times acceleration," Newton's Second Law of Motion.
Since the reaction force of a shock absorber depends on velocity, not
acceleration, adding up the forces results in a nasty little math problem
called a differential equation, which must be solved with differential
calculus. When the apple fell on Newton's head he tried to write an equation
for its motion using the math available in the 17th century. He couldn't
do it, so he invented differential calculus to solve the problem. He refused
to publish anything about calculus because he didn't think it was very
significant. It wasn't until others published articles about it that he
bothered to explain his invention.
Early
in the project one engineer commented, "If it wasn't for Isaac, we
wouldn't be able to do this."
One
must give credit where credit is due. (Go to top)
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