Safety - Flag
Johnson's flag mount
- Date: Thu, 31 Aug 2000
From: Ted Bennett
Subject: light pole for Greenspeed
List-Id: Recumbent Human-Powered Trikes <trikes.ihpva.org>
Back when my Greenspeed was new, I T-boned a car that
pulled out in front of me from a side street. The
driver didn't see me because the trike and I are lower
than the row of parked cars. I wasn't using the
flag supplied with the trike because I didn't like the
extra wind resistance and the flapping of the thing.
(I can't stand extra noise and rattles.) There were
a few interactions along the following lines:
"Hey, are you sure you should be
riding that thing on the roads? I can't see you."
"Oh? Then what are you
I decided to fabricate a pole, rigid so there was no
flapping and so that I could mount a light on it.
To minimize the weight, I chose aluminum tube, bent so
that the top couple of feet is vertical, and of a
diameter just under the inner diameter of the seat tube.
(I had to remove the glued-in plug at the top of the seat
tube to do this.) The tube was fixed in position
using a bolt through the threaded fitting at the top of
the seat tube that is standard on Greenspeeds. M5 I
believe. It was necessary to push a piece of wood
dowel inside the pole so that the bolt didn't crush the
The top of the tube is about seven feet above the ground,
and the top two feet or so is wrapped with a hideously
bright green tape and topped with one of those LED
flasher thingies. I chose one made by Eclipse
because it is only slightly wider than the pole itself
and can run in an up-and-down "chase" mode.
This worked well, but only for a short time. Turns
out that the AL tube allows enough flex that the
resulting waggling was enough to break the mounting of
the flasher, and it perished under the wheels of traffic.
The replacement is now attached by a custom made mount (aren't
drill presses handy things) which looks like it belongs
there, and has held up fine.
The only real drawback is that the pole, being
semipermanently attached, no longer allows me to store
the trike under my porch, and I can't ride under tractor
Anyone wanting to try my approach should be aware that
placing more lights up top results in a surprising amount
of leverage on the seat tube, something that Ian Sims may
be unenthusiastic about. For example, I tried
mounting a strobe light that is powered by a single D
cell but it perceptibly torqued the seat sideways in hard
turns and on bumpy roads. The obvious fix is to
remove the heavy bits (the batteries) to a low point on
the trike and run wires to the lights. Better yet
would be to arrange a row or several rows of LEDs in a
series of small holes drilled into the tube, with the
power source and electronics down low. Stay tuned.
- Recumbent riders often add a flag on the end of a rod as
it will help cars see you, especially with the seating so
low. Refer to this diagram for the
design to make a decal marked HPV to brighten it up. This
is done by:
- Printing out the letters on paper.
- Cut out each letter but keep them all together.
- Tape this to a piece of colored contact. (mine was
solid black)This is a 'sticky on one side' type of
film with a paper backing that is peeled off.
- Place all on a cutting board and cut out the letters
going right through to the contact.
- This gives you the individual letters to stick to the
- First mark the baseline on the flag with a pencil
before placing the letters to get them straight.
Thursday, 29 January 2009