From: freshair@iastate.edu (James W Gregory)
Subject: Need a better headlight system...
Organization: Iowa State University, Ames IA
Date: Fri, 6 Nov 1992 14:07:28 GMT

I'm looking for a better headlight system for use this winter when I'm
delivering pizzas.  My requirements:

1)  Must be able to last for at least four hours.
2)  Very bright (so I can see potholes in the dormitory parking
lots--I blew out a tire after hitting one of these because my previous
light was too dim :-( ).  At least 3 watts preferably.
3)  Will work in rain and snow, and at a temperature down to - 10 F or
so.
4)  Compatible with studded tires and/or tire chains.

The long run time seems to preclude any kind of battery system.  (I
could carry a set of spare batteries and change them when the others
go dim, but I'm afraid of getting stranded with two sets of dead
batteries on some night that I have to work late.)  Plus, the cold
temperatures supposedly will sharply reduce the power of gel cells (or
so I've heard).  

I'd prefer to use a generator system if possible.  Most types I've
used in the past, tho, slip when it is wet, and freeze up entirely
when they get snow and ice on them.  Bottom-bracket-mounted generator
sets also would not work with chains or studded tires, since they rub
on the outer circumference of the tire.

I'm currently using a cheap generator set that I modified following
the suggestions of John Forrester in _Effective_ _Cycling_.  I put a
thick coat of epoxy on the outer periphery of the generator wheel,
then wrapped nylon mesh around and around the wheel, until the diameter
of the wheel was approximately 1.5 times as large as before.  The
epoxy I used (called "Plastic Steel") supposedly had finely ground
steel particles in it, so it is very hard and wears very little.
Since the diameter of the wheel is larger, the amount of force
required to get the generator turning (i.e. to generate enough
"starting torque") is less, and therefore the generator is less likely
to freeze up in adverse weather.  I used it for 4 hrs in the rain last
Sunday night, and it did not slip once.  Increasing the wheel diameter
does lower the total speed of the generator, and hence its power
output is lower.   To compensate, I took off the rear taillight
(replacing it with a vista light, which I think is one of the greatest
things to hit bicycling since the clincher tire) and used the
generator to power only the halogen-equipped headlight.  (The
headlight, by the way, is the head off of a focusable Radio Shack
flashlight.  This allows me to focus the headlight to adjust for
different riding conditions).  

I'm anxious to see how it works in snow.  John Forrester claims it
won't freeze up.  I hope he's right.  But I'd welcome anyone else's
ideas for a headlight that fits the abovementioned requirements.

-- 
-------------------------------------------------------------------------------
Jim Gregory      freshair@iastate.edu    |  "10,000 lemmings can't be wrong"
Dept. of Plant Pathology, ISU (by day)   |          - anonymous
Fresh Aire Delivery Services (by night/weekends)
From: jbrandt@hplredHPL.HP.COM (Jobst Brandt)
Date: Tue, 3 Nov 1992 16:16:46 GMT
Subject: SF Bicyclist shoots attackers
Organization: Hewlett-Packard Laboratories, Palo Alto, CA