Most motorcyclists have wondered about whether a black helmet is
hotter than a lighter color, like silver. The question is asked
quite frequently on Internet Forums, and there is no shortage of
opinions. Today I had a chance to actually test the theory for
myself, as I was considering a black helmet. It seems to be the only
color available right now in XL in the new Arai XC-Ram.
The story goes like this. We all know that dark colors absorb heat
and light colors reflect it. But many proponents of black helmetsclaim
that the 2 inch Styrofoam liner is a pretty darned good insulator.
They say that if there was any difference, it would only be a factor
at a standstill, that the moment you start moving, the wind will
dissipate the heat. But I don't go for subjective testing. As an
Engineering tech, I need to see concrete data.
I think those would be reasonable considerations, if the temps were
only a couple of degrees apart. And that is what I set out to prove
or disprove. Take a look at this test and my conclusions at the end.
I found the results to be very surprising.
Helmet Temperature Test
2012 Arai XC
Ram helmets Diamond Black vs Aluminum Silver
89 degrees. Mostly Sunny. Wind Speed Negligible. All air vents open.
Visors closed. Visors facing away from Sun. Air probes were placed
between comfort liner and inner styrofoam shell.
Test Equipment Fluke 87 Series 5 Multimeter with Temperature
Fluke 62 IR Thermometer
2 matched K Type Thermocouples with Air probe tips.
Here is a picture of the setup.
[TABLE="class: grid, width: 500, align: left"]
[TD]15 minutes *[/TD]
[TD]60 minutes **[/TD]
*Test error. I mistakenly inserted the probes in the sun, allowing
the probe for the silver helmet to
be exposed to direct sunlight for about 2 minutes, allowing it to
heat up. The first 15 minute sample may have been tainted, and
cannot be considered accurate.
** last 10 minutes of test were under cloud cover.
The first sample had me scratching my head, until I realized the
mistake I had made. But I knew that the temps would stabilize, and
it would not affect the subsequent samples.
1. The test proves that it is indisputable that at a standstill, a black helmet not
only gets hotter inside, but a lot hotter.
2. With a surface temperature 55 degrees above ambient temperature,
the black helmet was obviously absorbing a massive amount of heat.
The extremely high temperature of the black outer shell prevented
the inside of the helmet from
cooling down. While the inside of the silver helmet cooled down
under cloud cover due to the lower external surface temperature, the
inside of the black helmet continued to rise, even though the outer
temperature dropped. Getting the helmet out of the sun did not
provide any relief inside the helmet.
3. Even though this test was done at a standstill, I do not believe
that hot 90 degree air flowing over a helmet at speed could have
made much of a difference in reducing inside temperatures. Not only
that, but on a Goldwing, not that much air hits the helmet.
4. I had hoped for continuous sun. But the presence of clouds at the
end of the test turned out to be a blessing. It shows that once you
stop, even for a short time, the temps rise so rapidly on the outer
surface of a black helmet, that once you start moving, it can never
5. The temperatures of both helmets reached their peak fairly
rapidly, and then either stopped rising, or rose at a lower rate.
6. I was very surprised that the internal temperature of the Silver
helmet only rose about 6 degrees above ambient temperature up to 45
minutes. I think this may prove that wearing a helmet is cooler than
no helmet. I may go out in the Sun tomorrow and measure the
temperature of my bare head after 15 minutes.
7.Those who believe their black helmets are
not any hotter are kidding themselves.
I did not have time to make this a highly detailed experiment. But
the results are so skewed that the limited samples provided all the
data that was needed. I believe this is the only actual experiment
that has been done on this subject. Everything else on the Internet
is only opinions, which vary wildly. I think that my test now proves
the answer definitively. I would like to put the probes inside
the helmet and test the helmets while moving, but then I would not
be able to return them.
EDIT: It also should be noted that with a human head in the helmet,
those internal temperatures would have likely been higher for both helmets.
Not only would there be less ambient air to keep the temps down, but
our heads generate heat as well. The silver helmet would
not have remained as cool as it appears in the test. But at the same
time, the black helmet temps would have likely become unbearable.
This test should not be construed as an example of what the actual
temps are inside a helmet while riding, but rather looked at solely
by the differences between the two helmets.
The Black helmet is being returned, and I am going to wait for the
sliver one to arrive.
I hope this helps anyone considering a black helmet.
FWIW, the Diamond Black Arai is
gorgeous. I wish the results had been different.