Motorcycle Mirrors for Fat People
OK, here's the background ... I'm a "plus-size" male riding
a 2003 BMW K1200GT bike. The GT originally came with the
round "Mickey-Mouse ears" mirrors used by several BMW models,
attached to the instrument clusters on each handgrip. I had
two problems with the stock mirrors. First, I'm wide enough
that I couldn't see behind me without some body contortions;
the normal view from my riding position was of my shoulders.
(Of course, I could tilt the mirrors outward, to avoid my
shoulders, but that just exacerbated the issue of not being
able to see directly behind me, and increased the
aforementioned contortions.) And, secondly, the stock
mirrors' lenses weren't wide enough to give me a good field
of view out to the sides (unless tilted outward, as mentioned
above).
I quickly found that a popular "upgrade" to the GT is the
installation of the wide-oval, K12RS-style mirrors. It's a
simple plug-n-play substitution, requiring no modification to
the bike or mirrors, and the new mirrors were available at my
local dealer for about $90 a pair. In addition to having
lenses about 25% wider than the stock GT type (although
similarly narrower from top to bottom -- about 3"x5" vs 4"
round), the RS mirrors attach to the bike via sculpted-plastic,
two-rib arms that just look nicer (and more solid) than the
spindly, metal-bar, stock-GT mirror shafts. [But, as
we'll see later, I soon destroyed that sleek look. :-)]
Each KRS-style arm has a rotational friction joint
toward the base, which allows the mirror to fold back to the
rear upon stiff collision. I suspect that the original GT
mirrors would do something similar, just by their metal shaft
turning in the bolt hole. One note: the RS mirrors' arms will
slightly contact the stock windshield at full lock in either
direction, though I don't remember if it happens at all
windshield positions. They also tag my
Cee Bailey's +6"
windshield, but not enough to break anything or interfere with
steering.
The RS mirrors sorta' solved either problem, but not fully.
Their inside edges more or less correspond in position to the
stock mirrors, which means that the outer edge is an inch or
so farther out. So, by tilting them in a bit, I could see more
behind me than before, but still not as well as I might like.
And, by tilting them out, I could see better to the sides, but
again not optimally. So, setting aside the first problem
temporarily, I continued to address the second.
My first thought was to stick some of the little round,
convex-mirror, "fish-eye" lenses to the outside portion of
the RS mirrors. That would allow me to see vehicles in my
blind spots to the sides, but the stick-ons that were large
enough to be useful covered up way too much of the total
mirror surface. (I guess I should mention here that, in
addition to being old and fat, I'm damned near blind, and wear
trifocal glasses.) Also, of course, the big fish-eyes reduced
my view behind to less than what I had with the round mirrors.
Then someone on the Internet BMW
Riders (IBMWR) email list pointed me to
Multivex mirror
lenses. These are add-on lenses
that are flat on the inner 1/2 or more, but convex curved on
the outside edges. Once you get used to them, they almost
completely eliminate blind spots, allowing you to see a vehicle
in the mirrors right up until it enters your direct peripheral
vision. The lenses just stick onto the existing mirrors with
double-sided tape. There's a thin gap left, but I filled it in
on the top and sides with black silicone caulk. The Multivex
part numbers for the RS mirrors are 01031LH and 01032RH. I
love 'em.
So, now that the side-view problem had been handled, what to do
about the view behind? Well, it's simple geometry, really -- the
obvious answer was that the spread of the mirrors had to be
significantly wider than me (which is saying something, as I'm
significantly wide) in order for my reflected views to converge
behind me. I perused various internet forums (fora?) for
mirror-related threads, and I looked through after-market
catalogs for mirror extenders and such. On a previous bike, I
had a pair of
Saeng windshield-mounted auxiliary mirrors, but I wasn't
much impressed by them. I thought I had a hot lead with the
Verholen fairing-mounted mirrors, but after exchanging
some notes with a gentleman who had them installed on his bike,
I learned that their tip-to-tip measurement was no more than
that of the RS mirrors. Back to the drawing board ... I
bought a couple of small, cheap mirrors at the local
motorcycle super-store, and played around with various ideas
on attaching them to the RS stalks such that they extended out
past the regular mirrors. But, not only did that look cheap
and ultra-dorky, the results were very non-sturdy, and usually
interfered greatly with the windshield or other parts.
Meanwhile, winter arrived, and I moved my bike into the garage
for an extended session of maintenance and farkling.
The mirror issue sorta' hung in limbo for a while, until one
day I started thinking about somehow extending the actual
RS-mirror arms. I measured the upper and lower ribs of the
arms for cross-section, taper, and what have you. I
conducted thought experiments and made scratch-paper designs
for inserting a length of plastic or metal tubing into the
middle of the stalk, or even flattening two tubes into oval
shapes and lengthening the upper and lower ribs individually.
(BTW, I say "I" here a lot, but actually I was with a buddy
who was working on his bike, too, and we were constantly
bouncing ideas off one another, and kibitzing and whatnot, so
most things were sorta' collaborative efforts with constant,
real-time peer review -- most helpful.)
Anyway, nothing really panned out, and spring was approaching.
So, one day, before I could really think long enough to stop
myself, I just grabbed a nearby saber saw and cut one of the
RS mirrors in half, while it was still on the bike! Holding
the severed mirror head and looking at the stub of stalk still
attached to the instrument cluster, I thought to myself, "now
I really need to get something in place, or I'm gonna have to
go order another pair of mirrors (right after I clean all this
black plastic 'sawdust' off my bike)".
So, the no-nonsense engineer in me came forward and decided:
we need reasonable strength and rigidity, not too much weight,
and a sturdy but relatively simple and easy assembly. I
quickly decided that the top and bottom ribs could each be
extended by a flat piece of metal, and that the plastic
surfaces of the ribs could be notched so that the metal
extensions would fit more or less flush (on the outsides). I
originally was thinking to screw the metal to the plastic, but
changed that to a pair of bolts at each end going through both
metal plates and the plastic stalk in between. It wouldn't
look pretty, but maybe I could find something to cover it.
Grabbing some 1/8-inch steel stock I had lying about in the
garage, I made two "rib extensions" that would extend the
mirrors out an additional four or five inches on either side.
To roughly match the taper of the original plastic ribs, I
cut three sides with with a saber saw (using the existing
edge of the stock for the leading side of the extensions) and
then used a bench grinder and a file to clean up and round the
edges and corners. The resulting dimensions were:
Once I had the extension pieces, I clamped them to the divided
mirror parts, marked the end positions, and then notched the
plastic ribs (using a Dremel® tool with a cut-off wheel) to
accept the extensions. (Actually, only the upper rib ends were
fully "notched". The lower ones were more sorta' flattened at the
appropriate angle.) And, on the inside piece (the mounting-stalk
end), I inserted a large hex-nut between the ribs, to widen the
gap and lessen the angle at which it tapered. It sounds more
complicated than it is ... see the photos.)
To attach the extensions to the plastic ribs, I again clamped
the extensions in place, then drilled a pair of holes at each
end of the assembly, piercing upper and lower extensions, and
the plastic in between. Note that there is some sort of
flat, metal reinforcement embedded within the plastic on the
outer end, near the ball joint. Originally, I was going to
use regular pan-head bolts, cut to the needed lengths, and
maybe acorn nuts on the bottom, to fasten the pieces together.
At some point I realized that I could countersink the holes
at the head ends, use flat-head bolts, and get a more flush
fitting. Along this train of thought, I also realised that
I didn't have to use nuts -- since the extension pieces were
fairly thick steel, I could just tap threads into the lower
holes and the extensions themselves would be the "nuts", again
giving a flush surface. And, somewhere along the line, I
decided to reverse one bolt at each end, so that one of each
pair would thread in from the top, and one from the bottom.
So, I redrilled the holes in the extensions appropriately
(a smaller size for the holes to be tapped, larger for rest),
countersank or tapped the holes as needed, and installed
flat-head bolts which were then ground flush (with the Dremel®
tool) where they protruded. I ended up using 10-32 stainless
steel bolts (just because that's what I had -- purists will
want to used a metric size, I'm sure). After everything was
assembled and tested, I backed out the bolts a bit, applied
some Loctite®, and tightened everything back up.
Again using the Dremel® tool, I went over the
metal pieces, rounding edges and corners such that the
extensions "flowed" as much as possible into the lines of
the plastic end pieces. I rubbed the whole assembly with
my hands, looking for points and sharp edges to grind down.
The end result was a very sturdy, not too heavy, extended
mirror. The look was sorta' robotic-arm-ish, in a geeky
and somewhat dorky way. But, I'm old and fat anyway,
and certainly no fashion plate, so the looks were entirely
secondary. The thing met all of its initial requirements,
and did the job for which it was designed. Mounted on the
bike, the extended mirror arm easily let me see a point
directly behind me, while the Multivex lens still provided
great coverage of the traditional blind spot to the side.
Woo hoo!
Notice that the space between the upper and lower extension
bars just cries out for farkles. :-) It would make an
ideal place to install a bank of switches, or LED indicators
or turn signals, or who knows what ... I decided to
just slip something over mine for the nonce, to cover up the
hacked-ends look. I thought about a piece of rubber or
neoprene hose, stretched to fit, but I ended up using some
1.5-inch-diameter, 2:1 heat-shrink tubing, black. I slipped
it over the whole shebang, shrank it with a Bernz-O-matic®
torch (careful!), and trimmed the ends. It worked great!
I'll probably add another layer of heat-shrink, just to
toughen it up a bit, and then wrap a band of electrical tape
around the arm where it hits the edge of the windshield at
full lock.
So, with the prototype built and working, I pretty quickly
(one evening) did the other mirror. Went for a test ride --
oh my, they're awesome! On a couple of subsequent commutes
to work, I was able to clearly see directly behind me (which
is a must in rush-hour interstate traffic) with just eye
movements, and I still had all of the excellent side vision
provided by the Multivex mirror lenses. This mod immediately
became one of those "how did I ever live without it?"
things.
So, to anyone with a "width" issue in using your mirrors, I
can highly recommend this sort of construction, or something
similar, as a potential solution. Cost is fairly modest, if
you have a pair of RS mirrors and are minimally handy with
small power tools. This web page should supply all the
instuctions needed, as there's nothing really critical
involved. If this idea solves your problem, I'll accept
polite applause with modesty and grace (but, if you
irreparably screw up your mirrors or your bike, or hurt
yourself with a tool or technique, it's all your fault and
you're on your own).
Copyright © MMXII by William K. Brummett. All rights reserved.
The background image was sent to me by someone. If
it's rightfully yours and needs to be attributed, gimme a yell.
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