Lezyne Deca Drive 1500XXL Report

On Sat, 4 Mar 2017 17:24:52 -0800, sms
wrote:

There's a new light with a mount that automatically rotates the light
based on the way you are looking. It has a wireless transmitter that you
mount on your helmet.

I once prototyped a similar contrivance that mounted an IR spotlight
on your helmet. The headlight would then track the IR spot. Some
correctly concluded that it would be easier to just mount the light on
the helmet. These days, my guess(tm) that such a device might use
inertial MEMS sensors to determine head direction.

But you may be over-thinking this. Yes, with a light that delivers some
light to the sides, and upwards, you may not always need that side and
upwards spill, but it'd be hard to design a system that only had that
spill when you were turning are looking for street signs or branches.

T'is better to have over-thought and over-killed, than to never have
thought at all. As I indicated, I don't know what is optimum. I've
tried a "brick wall" side spill light, and it sucked because of the
lack of peripheral illumination. Similarly, one big hot spot with a
slow fade and wide illumination angle is bad because it blinds
oncoming traffic. I don't think we can pontificate as to what might
be the optimum beam pattern. The best we can do is play with
different ideas, and see how well, or badly, they work.

A slightly larger rechargeable battery and continuous side and upward
spill is fine.

Methinks more spill pointing downward onto the roadway, and less spill
in the face of oncoming traffic, might be a useful modification.

Proper optics would limit the intensity of the spill so
you didn't blind oncoming traffic.

Have you already forgotten my adaptive lighting scheme, where the
headlight intensity is controlled by the oncoming headlights. It's an
old scheme that's been around in automobiles since the 1950's or
perhaps earlier. What new today is that you can use the bicycle
headlight to also act as a sensor. One can also adjust the beam tilt
angle to match the oncoming headlights, so that bumps in the roadway
do not raise the beam into oncoming traffic. I think this is
mandatory in some jurisdiction on autos with HID headlights:
http://auto.howstuffworks.com/adaptive-headlight1.htm



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 3/4/2017 4:18 PM, jbeattie wrote:
On Saturday, March 4, 2017 at 9:36:54 AM UTC-8, Frank Krygowski wrote:

I'm astonished. What's the "period" on "periodically" whacking tree
branches? How badly have you been hurt by these "whacks"? Where on the
road are you riding when that happens? What do the SUV drivers and
truck drivers do when they come to these tree branches? Do you know
cyclists who have been injured by these tree branch whacks? Is there no
agency that keeps the streets clear of such hazards? Why would people
not demand that?

I'm astonished because I live in an area that gets _far_ more snow than
you do. Our club has (at least) weekly rides through a forested
metropolitan park, which gets far less truck traffic than any ordinary
street. Yet I may duck thin twigs with wet leaves perhaps once per
year, but probably far less than that; and if I didn't duck, there would
be no consequences.

I've never come across "low overhanging branches" listed as a riding
hazard in any of the dozens of cycling books I own, nor in any of the
three or four cycling classes I've taken, nor in the curriculum guides
for the courses I taught, nor in any online instructional articles I'm
aware of.

I'm not saying it's impossible to come across a branch so low as to
constitute a hazard; but I think it's got to be about as rare as, say,
dodging a turtle crossing the road. Or in Portland, dodging a salmon
crossing the road.

I believe everyone outside this discussion group considers this a
negligible issue. Why is this group different??

I ducked twice today (bike lane) and had to take the lane on HWY 30 to get around a giant Laurel that had basically slid or grown across the bike lane.

Please explain "slid or grown." IME, the growing happens quite slowly,
and I've got no experience with plants that slide out into attack position.

It was hailing before the rain.

Are you saying the hail was enough to beat a branch down to where it
would hit you? While I don't wish to sound repetitious, that's yet
another thing I've never experienced and never heard of.

This is a little piece of my commute, and depending on the year and
season, you can do a lot of ducking.
https://www.youtube.com/watch?v=LuIEtk7nvAY

And that may be the prime explanation for the entire phenomenon. In my
view, riding in that bike lane is precisely equivalent to riding in a
gutter. I would not ride at normal bike speeds that close to the road's
edge, therefore I'd not give a moment's thought to those roadside bushes.

But look at 0:18 and 0:26. The branches, thin as they are, seem to be
higher than the adjacent SUV's - IOW, higher than any normal cyclist's
head.

At 0:37, the bike lane is effectively two feet wide and entirely in
reach of a passenger door opening. If traffic were blocked as shown in
places and I chose to get by, I'd probably pass on the left as normal
traffic does. If I did pass on the right, I'd be creeping by. At low
speed those twigs would not pose a hazard.

Understand, we have very few bike lanes around here. The few we have
are much wider and are clear of such shrubbery; yet I still generally
avoid them, mostly because of surface debris. Shrubbery would be
another reason to avoid them.

--
- Frank Krygowski

On 3/4/2017 8:13 PM, James wrote:
On 05/03/17 04:36, Frank Krygowski wrote:


I'm astonished. What's the "period" on "periodically" whacking tree
branches? How badly have you been hurt by these "whacks"? Where on the
road are you riding when that happens? What do the SUV drivers and
truck drivers do when they come to these tree branches? Do you know
cyclists who have been injured by these tree branch whacks? Is there no
agency that keeps the streets clear of such hazards? Why would people
not demand that?


While I was living in Brisbane, I used a section of road where there is
a painted on bike lane and young planted trees that overhang the bike
lane at times. They may have been trimmed, but a year ago I would move
just outside the bike lane to avoid branches.

/data=!3m6!1e1!3m4!1sM4L3bVhiqbK8iGQCb9-7xg!2e0!7i13312!8i6656!6m1!1e1
No injuries or other mishaps to report.

The trees don't seem to present the hazard being discussed. I'd think
that if they grew into hazards, cyclists would complain and the hazard
would soon be removed.

BTW, tree branches over sidewalks are an annoyance my wife and I
encounter, but of course, that's when walking, not bicycling. I have
been known to carry clippers and trim some of those. And on one local
hidden bike path (the kind of thing only school kids know as a
shortcut), I've cleared some weeds that were over-growing the path. But
I've never had to think about doing that on a road.

--
- Frank Krygowski

On 3/4/2017 2:08 PM, sms wrote:
On 3/4/2017 8:25 AM, jbeattie wrote:

snip

I periodically whack tree branches, too. After the recent snow storms,
there were lots of tree branches hanging into the roadways. It was a
real problem. Now the problem is residual blow-down and gravel --
which won't get swept for months.

You need to move to Frank's area of Ohio where the city does a really
good job of driving panel trucks down the right side of the street to
knock down low-hanging branches. They have a schedule for doing this,
similar to the street-sweeping schedule.

I suppose the city does occasionally drive trucks down the right side of
most streets. But like all the other trucks and SUVs that are taller
than cyclists, they do it just to get places. They drive on the right
because in this country, everyone drives on the right.

Do California drivers really dodge around low-hanging branches until
they become safety hazards for bicyclists? I remain astonished. And
I'd love to see photos.

(I have ridden in California, BTW. Los Angeles, San Francisco and
several smaller towns, plus country roads. Somehow, I never encountered
the hazards you fear.)

--
- Frank Krygowski

On 3/4/2017 1:09 PM, Sir Ridesalot wrote:
On Saturday, March 4, 2017 at 12:36:54 PM UTC-5, Frank Krygowski wrote:
snipped a lot about lowhanging branches
I believe everyone outside this discussion group considers this a
negligible issue. Why is this group different??

--
- Frank Krygowski

Maybe it's because in OUR areas it is a thing we encounter frequently. The problem with you Frank is if you don't personally see something then in your mind it simply can not exist.

Got photos?

Seriously: Three or four photos of real branches hanging over a real
road as low as a cyclist's head would do a lot to convince me. It would
be even better if the photos showed the branches that low over the
portion of the road where a competent cyclist would ride.

The usual advice is to ride at _least_ three feet from the right edge of
the road, and many say further left than that is better.

Sir, you've posted photos of other things before. If these hazards
really are so common, you should be able to get the photos in a day or two.


--
- Frank Krygowski

On 3/4/2017 6:12 PM, Frank Krygowski wrote:

Sir, you've posted photos of other things before. If these hazards
really are so common, you should be able to get the photos in a day or two.

And I've posted photos of low hanging branches over-hanging the right
side of the right lane. And not in "the gutter." It's hopeless. You are
like Donald Trump and "alternative facts." No amount of proof, and no
number of people asserting that they have experienced this issue, will
ever convince you of something you've already convinced yourself is not
true.

On Saturday, March 4, 2017 at 6:01:34 PM UTC-8, Frank Krygowski wrote:
On 3/4/2017 4:18 PM, jbeattie wrote:
On Saturday, March 4, 2017 at 9:36:54 AM UTC-8, Frank Krygowski wrote:

I'm astonished. What's the "period" on "periodically" whacking tree
branches? How badly have you been hurt by these "whacks"? Where on the
road are you riding when that happens? What do the SUV drivers and
truck drivers do when they come to these tree branches? Do you know
cyclists who have been injured by these tree branch whacks? Is there no
agency that keeps the streets clear of such hazards? Why would people
not demand that?

I'm astonished because I live in an area that gets _far_ more snow than
you do. Our club has (at least) weekly rides through a forested
metropolitan park, which gets far less truck traffic than any ordinary
street. Yet I may duck thin twigs with wet leaves perhaps once per
year, but probably far less than that; and if I didn't duck, there would
be no consequences.

I've never come across "low overhanging branches" listed as a riding
hazard in any of the dozens of cycling books I own, nor in any of the
three or four cycling classes I've taken, nor in the curriculum guides
for the courses I taught, nor in any online instructional articles I'm
aware of.

I'm not saying it's impossible to come across a branch so low as to
constitute a hazard; but I think it's got to be about as rare as, say,
dodging a turtle crossing the road. Or in Portland, dodging a salmon
crossing the road.

I believe everyone outside this discussion group considers this a
negligible issue. Why is this group different??

I ducked twice today (bike lane) and had to take the lane on HWY 30 to get around a giant Laurel that had basically slid or grown across the bike lane.

Please explain "slid or grown." IME, the growing happens quite slowly,
and I've got no experience with plants that slide out into attack position.

On 05/03/17 13:05, Frank Krygowski wrote:
On 3/4/2017 8:13 PM, James wrote:
On 05/03/17 04:36, Frank Krygowski wrote:


I'm astonished. What's the "period" on "periodically" whacking tree
branches? How badly have you been hurt by these "whacks"? Where on the
road are you riding when that happens? What do the SUV drivers and
truck drivers do when they come to these tree branches? Do you know
cyclists who have been injured by these tree branch whacks? Is there no
agency that keeps the streets clear of such hazards? Why would people
not demand that?


While I was living in Brisbane, I used a section of road where there is
a painted on bike lane and young planted trees that overhang the bike
lane at times. They may have been trimmed, but a year ago I would move
just outside the bike lane to avoid branches.

/data=!3m6!1e1!3m4!1sM4L3bVhiqbK8iGQCb9-7xg!2e0!7i13312!8i6656!6m1!1e1

No injuries or other mishaps to report.

The trees don't seem to present the hazard being discussed. I'd think
that if they grew into hazards, cyclists would complain and the hazard
would soon be removed.

Google street view images may not be representative of precisely how the
shrubbery was when I was using that road.

When I was using that road I recall having to either duck out of the way
of low branches, or move right and into the "car lane".

I have complained about overhanging branches to council in the past.
Eventually they get tidied up, but only _after_ they have become a problem.

--
JS

On 3/4/2017 8:38 PM, Jeff Liebermann wrote:


Diversion: When measuring headlight lumens, I suspect one projects
the headlight beam against a white wall that's perpendicular to the
beam. That makes measurements fairly easy. However, when one
actually uses the headlight, it's projected against the roadway, which
is almost parallel to the beam, and certainly not perpendicular. If a
uniform beam is deemed to be desirable, then the light should be
brighter at the top of the beam, and dimmer at the bottom. Just a
thought.

I don't think that's a diversion at all. It's an important optical
principle, and it's one that's used for all the best headlights, whether
they're for bikes or for motor vehicles. It results in a beam that
evenly lights the road as seen by the operator, and it prevents
near-field hot spots that (as you've described) harm night vision.

--
- Frank Krygowski

On 3/4/2017 8:57 PM, Jeff Liebermann wrote:
On Sat, 4 Mar 2017 17:24:52 -0800, sms
wrote:

There's a new light with a mount that automatically rotates the light
based on the way you are looking. It has a wireless transmitter that you
mount on your helmet.

I once prototyped a similar contrivance that mounted an IR spotlight
on your helmet. The headlight would then track the IR spot. Some
correctly concluded that it would be easier to just mount the light on
the helmet. These days, my guess(tm) that such a device might use
inertial MEMS sensors to determine head direction.

I've built two much simpler systems to steer headlights using a
handlebar mounted control. That goes back probably 15 years. Before
that, I had a commercial headlight (Vistalight, IIRC) that was easy to
pivot when it was mounted on the handlebars. No wireless nor inertial
sensors needed.

Heck, remember the Tucker?

--
- Frank Krygowski