Light works

On Saturday, August 30, 2014 5:23:48 PM UTC-4, jbeattie wrote:
On Friday, August 29, 2014 11:30:42 PM UTC-7, James wrote:

On 30/08/14 00:34, jbeattie wrote:



On Thursday, August 28, 2014 11:42:20 PM UTC-7, Lou Holtman wrote:







I think a roadbike with 8 bar inflated 23 mm wide tires on Belgium







cobblestones take a lot more beating than a ATB with 2.5 inch



wide







nobby tires with front suspension.







Maybe, but most of us don't ride on Belgian cobbles -- and look at



what they do to road bikes. Paris Roubaix is littered with broken



parts.







I don't know if a hub dynamo is a good thing on a mountain bike and



defer to those who use them. Personally, I wouldn't bother with one



because of all the wiring and additional crap on my bike that would



get infrequent use, being that night trail riding is not something I



would do often. A battery light would be a more reasonable option,



and I could simply shift a light from my road bike for trail riding.



I also wonder whether a dynamo would put out enough light when I was



picking my way up forested single track at 4mph. It seems to add so



much complexity without a real pay-off. The calculus is different on



a commuter that gets a lot of night time use.







Um, complexity? If anything there is *less* complexity, because the



power source is integral with the bike - where as a battery must be



strapped on somewhere, and usually still has a cable from battery to light.







Folks to 24h enduro MTB events with dynamo lights as their primary light



source. It can't be that bad, Jay, in fact the people who use them



often use them because they decide the dynamo light option is _better_.







--



JS



Complexity is a bunch of whirling magnets/coils in a hub, wiring, fixed mount lamps and circuitry to provide a stand light. If you believe the DYI set, nothing OTC is good enough, and you have to spend an afternoon at the kitchen table soldering LEDs, diodes,capacitors, etc. And then you have to do it all over again for bike number two, three, four, etc. I just snatch my battery light off one bike and throw it on another -- it takes about a minute.



My brother does 24 hour mountain bike races and uses a battery light. A summer race around here involves maybe seven or eight hours of darkness, and most of the 24 hour races are run on a circuit, so you just bring a spare battery -- assuming your battery has a less than seven hour life. My light has a 10 hour run time on "low" (350 lumens).



Again, I think there is a pay off on commuter bikes and bikes that are routinely run in the dark for long periods of time or on an out and back with no way to change a battery (e.g. PBP). Most of my night riding is well within my battery life, and a dynamo would just save me from forgetting to charge my battery -- which happens now and then. On those days, I have to rely on my flea-watt USB rechargeable "see me" Nashbar light. http://www.nashbar.com/bikes/Product...3759____204774 And I stick to the lighted arterials instead of going home up and down steep, dark streets with broken concrete, which is my preferred route some nights.



I used the Nashbar light today riding in the rain (first rain in over a month. It was great, except the pavement was too slippery). No way I would put a hub dynamo on my super-cool CAAD 9 rain bike.



-- Jay Beattie.

amen !

On 8/30/2014 6:33 PM, Phil W Lee wrote:
Sir Ridesalot considered Sat, 30 Aug 2014
10:10:17 -0700 (PDT) the perfect time to write:


Reading the entire thread I see a post where you say you are an electrical engineer.
Why don'y you just design something tthat you feel fits the needs of
nightime trails
MTB riders and test it then sell the design to a manufacturer?

The major design consideration with bicycle lights is the optics, not
the electronics.
Lots of light is useless if it all goes where you don't need it.

And unfortunately, optics are quite difficult to do properly in one's
home shop. At least, they have been for me. I've built some very nice
looking headlights, with excellent LEDs in them, and been very
disappointed with their illumination of the road.

--
- Frank Krygowski

On 8/30/2014 5:23 PM, jbeattie wrote:

Complexity is a bunch of whirling magnets/coils in a hub, wiring,
fixed mount lamps and circuitry to provide a stand light.

Well, there are different types of complexity. To me, "whirling
magnets/coils" are a lot simpler than the cutting edge chemistry,
combustible materials, voltage regulation circuits and thermal
protection circuits of a Li-Ion battery. Heck, I could build a sort-of
dynamo using junk in my basement. I could never build a Li-Ion battery!

In reality, the complexity addressed by the manufacturer is largely
invisible to the customer. The "whirling magnet" stuff isn't important.
For the user, the choice in this matter has more to do with the amount
of attention or maintenance required to get light when it's needed.

If you believe the DYI set, nothing OTC is good enough, and you have to
spend an afternoon at the kitchen table soldering LEDs,
diodes,capacitors, etc.

Those are kind of like the guys who build their own tube amps to listen
to their vinyl albums. Their numbers are small, and range from geek
tinkerers to ... well, guys who view the world far, far different than
normal folks do.

And then you have to do it all over again for bike number two, three,
four, etc.
I just snatch my battery light off one bike and throw it on another --
it takes about a minute.

Heh. Unlike most Americans, I'm crazy enough to have several bikes.
And I'm crazy enough to have generators on almost all of them. I just
ride the bike, whichever one it is. If it happens to be dark, I flick a
switch and I get light.

If (and back when) I had only one bike, of _course_ it had a generator
light.

But YMMV, of course.

--
- Frank Krygowski

On 31/08/14 03:07, Joerg wrote:
James wrote:
On 30/08/14 02:06, Joerg wrote:
James wrote:


This then.. http://www.starbike.com/en/son-edelux-2-led-front-lamp/


Seems to come without bracket. They need to offer with bracket. The
light is super expensive as it is (would be over US$200) and then I'd
expect not to have to build any missing stuff myself. Also, I hope that
black ring in back ain't plastic or it won't survive.


You didn't look very far. There's a metal bracket to attach it to your
bars. All nice and smooth so you don't cut for knee as you fly over the
bars, etc.


Got a link?


I don't know why I bother. It was on display on the link above.

http://www.starbike.com/en/son-schmi...dlight-holder/

--
JS

On 31/08/14 03:10, Joerg wrote:
James wrote:
On 30/08/14 02:20, Joerg wrote:
Lou Holtman wrote:


You have to realize that your commute route is far from usual.


Not in the Netherlands but in some parts of the world that is usual :-)

Even in your area it can be. I lived in your country for six years, in
Zuid Limburg. I rode over into Belgium a lot and over there we had lots
of remote and rugged mountainous paths that people used as shortcuts.
Many times I almost cussed my dynamo-driven lights because uphill they
produced so little light that I had to hop off the bike and walk it,
mostly to avoid doing an endo in a pothole that I didn't see.


Was that with a modern LED headlight?


No, bulbs. Regular and halogen. But with LED it's not much better unless
you have a battery because the super-caps only power most lights for 5
mins or so (when the dynamo is out of juice).


Actually it is much better with LED lights. They produce good light at
lower speed, due to the efficacy of the LED compared to halogen. Lumens
per watt for LEDs is many times better.

https://www.led-lighthouse.co.uk/how...-are-led-bulbs

--
JS

On 31/08/14 07:23, jbeattie wrote:


Complexity is a bunch of whirling magnets/coils in a hub

The coil (singular) is stationary on the axle. There is a ring of
magnetic material that is attached to the hub shell.

Shall we now discuss the complexity of battery construction and chemistry?

, wiring,
fixed mount lamps and circuitry to provide a stand light.

All of which is also usually a part of a battery powered solution -
wiring, mounting hardware, and circuitry to regulate the battery voltage
and supply the LED with a constant current.

If you
believe the DYI set, nothing OTC is good enough, and you have to
spend an afternoon at the kitchen table soldering LEDs,
diodes,capacitors, etc. And then you have to do it all over again
for bike number two, three, four, etc. I just snatch my battery
light off one bike and throw it on another -- it takes about a
minute.


I ride with guys who have lights like that. On several occasions they
have asked me to ride home with them because their battery has died or
their light has become faulty. Yay for their cheap Chinese lumen
boasting. I'd rather reliable.

My brother does 24 hour mountain bike races and uses a battery light.

Good for him. This guy produces lights for 24h MTB racing - including a
dynamo system - because people want them. http://www.cncdelite.com/

A summer race around here involves maybe seven or eight hours of
darkness, and most of the 24 hour races are run on a circuit, so you
just bring a spare battery -- assuming your battery has a less than
seven hour life. My light has a 10 hour run time on "low" (350
lumens).

I'd prefer not to have to stop.

Again, I think there is a pay off on commuter bikes and bikes that
are routinely run in the dark for long periods of time or on an out
and back with no way to change a battery (e.g. PBP). Most of my night
riding is well within my battery life, and a dynamo would just save
me from forgetting to charge my battery -- which happens now and
then. On those days, I have to rely on my flea-watt USB rechargeable
"see me" Nashbar light.
http://www.nashbar.com/bikes/Product...3759____204774 And
I stick to the lighted arterials instead of going home up and down
steep, dark streets with broken concrete, which is my preferred route
some nights.

I never worry about what light to attach. I get on my bike and ride it.

I used the Nashbar light today riding in the rain (first rain in over
a month. It was great, except the pavement was too slippery). No way
I would put a hub dynamo on my super-cool CAAD 9 rain bike.

I do most of my riding on my uber cool custom bike. I get compliments
from other riders when they see how my light illuminates the road at
night, and that it turns on automatically too. If I enter a race, it
takes me only a few minutes to swap the front wheel and front brake.
(Remember my front rim with the dynamo has a ceramic brake surface,
where as the wheel I race with doesn't - so I swap calipers and use
different brake blocks.)

http://www.gelliecustombikeframes.co...00km-re-paint/

https://www.flickr.com/photos/55102679@N05/14904578498/

https://www.flickr.com/photos/55102679@N05/14948765991

--
JS

On 31/08/14 08:30, Phil W Lee wrote:
Joerg considered Sat, 30 Aug 2014
10:13:04 -0700 the perfect time to write:

wrote:
AMAZING

each new visit to an old search question brings an AVALANCHE of material as here

https://www.google.com/#q=EFFECT+OF+...BICYCLE+WHEELS


I am not concerned about rotating mass but more about suspension
behavior. That becomes less than ideal if the non-suspended side gets
heavier. Goes for pretty much aany kind of vehicle.

If it were that big an issue on a bicycle we wouldn't have disc brakes
though, would we?

The vital thing isn't absolute mass but the ratio between sprung and
unsprung mass.
Given that the rider accounts for such an overwhelming majority of the
mass, a few grams added to the hub in return for decent and reliable
lights is generally regarded as a very worthwhile trade-off.
And of course, LEDs are far more resistant to shock and vibration than
filaments.


Don't confuse the issue with logic, Phil.

--
JS

On Sat, 30 Aug 2014 14:46:03 -0700, Jeff Liebermann
wrote:

On Sat, 30 Aug 2014 10:04:18 -0700, Joerg
wrote:

Head lamps are outright hazardous where I ride. Gets you tangled into a
tree branch in a jiffy and then there's probably going to be a rescue
effort followed by an obituary.

Drivel: I get mildly irritated when some calls the front light a
"head" light, and the rear light a "tail" light. We inherited those
terms from the horse and buggy era. They apply nicely to horses,
donkeys, mules, and other beasts of burden, but not motor or human
powered vehicles. Unless you plan to have your bicycle pulled by one
of these, please use a more appropriate term.

It's also not a "lamp", which implies that something burning is
producing the light. Unless you use fire to illuminate your path,
please use the term "light" instead.


Hmmm... My dictionary translates "Lamp" as "an artificial source of
visible illumination"...
--
Cheers,

John B.

On Saturday, August 30, 2014 5:46:03 PM UTC-4, Jeff Liebermann wrote:
On Sat, 30 Aug 2014 10:04:18 -0700, Joerg

wrote:



Head lamps are outright hazardous where I ride. Gets you tangled into a

tree branch in a jiffy and then there's probably going to be a rescue

effort followed by an obituary.



Drivel: I get mildly irritated when some calls the front light a

"head" light, and the rear light a "tail" light. We inherited those

terms from the horse and buggy era. They apply nicely to horses,

donkeys, mules, and other beasts of burden, but not motor or human

powered vehicles. Unless you plan to have your bicycle pulled by one

of these, please use a more appropriate term.



It's also not a "lamp", which implies that something burning is

producing the light. Unless you use fire to illuminate your path,

please use the term "light" instead.



We return you now to whatever it was I interrupted.







--

Jeff Liebermann

150 Felker St #D http://www.LearnByDestroying.com

Santa Cruz CA 95060 http://802.11junk.com

Skype: JeffLiebermann AE6KS 831-336-2558

000000000000000000000


try here

http://www.summitracing.com/search/d...d=spot%20lamps

On Saturday, August 30, 2014 5:23:48 PM UTC-4, jbeattie wrote:
On Friday, August 29, 2014 11:30:42 PM UTC-7, James wrote:

On 30/08/14 00:34, jbeattie wrote:



On Thursday, August 28, 2014 11:42:20 PM UTC-7, Lou Holtman wrote:







I think a roadbike with 8 bar inflated 23 mm wide tires on Belgium







cobblestones take a lot more beating than a ATB with 2.5 inch



wide







nobby tires with front suspension.







Maybe, but most of us don't ride on Belgian cobbles -- and look at



what they do to road bikes. Paris Roubaix is littered with broken



parts.







I don't know if a hub dynamo is a good thing on a mountain bike and



defer to those who use them. Personally, I wouldn't bother with one



because of all the wiring and additional crap on my bike that would



get infrequent use, being that night trail riding is not something I



would do often. A battery light would be a more reasonable option,



and I could simply shift a light from my road bike for trail riding.



I also wonder whether a dynamo would put out enough light when I was



picking my way up forested single track at 4mph. It seems to add so



much complexity without a real pay-off. The calculus is different on



a commuter that gets a lot of night time use.







Um, complexity? If anything there is *less* complexity, because the



power source is integral with the bike - where as a battery must be



strapped on somewhere, and usually still has a cable from battery to light.







Folks to 24h enduro MTB events with dynamo lights as their primary light



source. It can't be that bad, Jay, in fact the people who use them



often use them because they decide the dynamo light option is _better_.







--



JS



Complexity is a bunch of whirling magnets/coils in a hub, wiring, fixed mount lamps and circuitry to provide a stand light. If you believe the DYI set, nothing OTC is good enough, and you have to spend an afternoon at the kitchen table soldering LEDs, diodes,capacitors, etc. And then you have to do it all over again for bike number two, three, four, etc. I just snatch my battery light off one bike and throw it on another -- it takes about a minute.



My brother does 24 hour mountain bike races and uses a battery light. A summer race around here involves maybe seven or eight hours of darkness, and most of the 24 hour races are run on a circuit, so you just bring a spare battery -- assuming your battery has a less than seven hour life. My light has a 10 hour run time on "low" (350 lumens).



Again, I think there is a pay off on commuter bikes and bikes that are routinely run in the dark for long periods of time or on an out and back with no way to change a battery (e.g. PBP). Most of my night riding is well within my battery life, and a dynamo would just save me from forgetting to charge my battery -- which happens now and then. On those days, I have to rely on my flea-watt USB rechargeable "see me" Nashbar light. http://www.nashbar.com/bikes/Product...3759____204774 And I stick to the lighted arterials instead of going home up and down steep, dark streets with broken concrete, which is my preferred route some nights.



I used the Nashbar light today riding in the rain (first rain in over a month. It was great, except the pavement was too slippery). No way I would put a hub dynamo on my super-cool CAAD 9 rain bike.



-- Jay Beattie.

(((((((((((((((((


http://goo.gl/Q1c3K6