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  #1  
Old March 5th 17, 07:56 PM posted to rec.bicycles.tech
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Default More About Lights

Since you people have been talking about lights I've been looking. Like sms I really don't like the idea of having normal batteries that wear out quickly or the idea of always keeping your battery on charge.

This means you need a bulb generator or a hub generator. The hub generator seems a good answer but they don't appear to make half of the power of a bulb generator.

But that's a little hard to tell since they seem to have a great deal of trouble listing the output of the various dynamos.

You can get a 6 watt bulb generator but the hubs appear to all deliver 3 watts.

Now there are extremely efficient hubs that even Frank wouldn't have any trouble peddling in his old broken down and crippled state.

But when you look up the lights you find the same problem - you have a very difficult time finding power in and lumens out.

There are a few things that I really like the idea of in a commuter bike:

A front wheel hub generator - the German Schmidt which is extremely reliable and apparently is 78% efficient so Jorge could not complain that he is having trouble pedalling against the tide.

The Shimano Alfine is an 11-speed rear hub which has the decided advantage of being able to put a total cover chain guard around the entire chain and SINGLE SPEED front ring and still be able to leap tall buildings in a single bound.

Now building this set of wheel would cost the better part of a thousand dollars and we're all a bunch of cheapskates.

But with bikes costing $5K+ I'm sure you could build the perfect commuter for half that amount.

  #2  
Old March 5th 17, 08:12 PM posted to rec.bicycles.tech
Sir Ridesalot
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Posts: 3,238
Default More About Lights

On Sunday, March 5, 2017 at 1:56:13 PM UTC-5, wrote:
Since you people have been talking about lights I've been looking. Like sms I really don't like the idea of having normal batteries that wear out quickly or the idea of always keeping your battery on charge.

This means you need a bulb generator or a hub generator. The hub generator seems a good answer but they don't appear to make half of the power of a bulb generator.

But that's a little hard to tell since they seem to have a great deal of trouble listing the output of the various dynamos.

You can get a 6 watt bulb generator but the hubs appear to all deliver 3 watts.

Now there are extremely efficient hubs that even Frank wouldn't have any trouble peddling in his old broken down and crippled state.

But when you look up the lights you find the same problem - you have a very difficult time finding power in and lumens out.

There are a few things that I really like the idea of in a commuter bike:

A front wheel hub generator - the German Schmidt which is extremely reliable and apparently is 78% efficient so Jorge could not complain that he is having trouble pedalling against the tide.

The Shimano Alfine is an 11-speed rear hub which has the decided advantage of being able to put a total cover chain guard around the entire chain and SINGLE SPEED front ring and still be able to leap tall buildings in a single bound.

Now building this set of wheel would cost the better part of a thousand dollars and we're all a bunch of cheapskates.

But with bikes costing $5K+ I'm sure you could build the perfect commuter for half that amount.


Once again; *SOME PEOPLE PREFER THE CONVENIENCE OF BATTERY LIGHTS FOR THEIR OWN USES!*

If I had to spend $2,500.00 for a commuter bicycle I'd seriously look at a used car just for commuting.

Cheers
  #3  
Old March 5th 17, 08:26 PM posted to rec.bicycles.tech
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Posts: 1,482
Default More About Lights

On Sunday, March 5, 2017 at 11:12:01 AM UTC-8, Sir Ridesalot wrote:
On Sunday, March 5, 2017 at 1:56:13 PM UTC-5, wrote:
Since you people have been talking about lights I've been looking. Like sms I really don't like the idea of having normal batteries that wear out quickly or the idea of always keeping your battery on charge.

This means you need a bulb generator or a hub generator. The hub generator seems a good answer but they don't appear to make half of the power of a bulb generator.

But that's a little hard to tell since they seem to have a great deal of trouble listing the output of the various dynamos.

You can get a 6 watt bulb generator but the hubs appear to all deliver 3 watts.

Now there are extremely efficient hubs that even Frank wouldn't have any trouble peddling in his old broken down and crippled state.

But when you look up the lights you find the same problem - you have a very difficult time finding power in and lumens out.

There are a few things that I really like the idea of in a commuter bike:

A front wheel hub generator - the German Schmidt which is extremely reliable and apparently is 78% efficient so Jorge could not complain that he is having trouble pedalling against the tide.

The Shimano Alfine is an 11-speed rear hub which has the decided advantage of being able to put a total cover chain guard around the entire chain and SINGLE SPEED front ring and still be able to leap tall buildings in a single bound.

Now building this set of wheel would cost the better part of a thousand dollars and we're all a bunch of cheapskates.

But with bikes costing $5K+ I'm sure you could build the perfect commuter for half that amount.


Once again; *SOME PEOPLE PREFER THE CONVENIENCE OF BATTERY LIGHTS FOR THEIR OWN USES!*

If I had to spend $2,500.00 for a commuter bicycle I'd seriously look at a used car just for commuting.

Cheers


I don't recall forcing anything on you. Or do you simply object to opinions?
  #4  
Old March 5th 17, 10:34 PM posted to rec.bicycles.tech
Sir Ridesalot
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Posts: 3,238
Default More About Lights

On Sunday, March 5, 2017 at 2:26:07 PM UTC-5, wrote:
On Sunday, March 5, 2017 at 11:12:01 AM UTC-8, Sir Ridesalot wrote:
On Sunday, March 5, 2017 at 1:56:13 PM UTC-5, wrote:
Since you people have been talking about lights I've been looking. Like sms I really don't like the idea of having normal batteries that wear out quickly or the idea of always keeping your battery on charge.

This means you need a bulb generator or a hub generator. The hub generator seems a good answer but they don't appear to make half of the power of a bulb generator.

But that's a little hard to tell since they seem to have a great deal of trouble listing the output of the various dynamos.

You can get a 6 watt bulb generator but the hubs appear to all deliver 3 watts.

Now there are extremely efficient hubs that even Frank wouldn't have any trouble peddling in his old broken down and crippled state.

But when you look up the lights you find the same problem - you have a very difficult time finding power in and lumens out.

There are a few things that I really like the idea of in a commuter bike:

A front wheel hub generator - the German Schmidt which is extremely reliable and apparently is 78% efficient so Jorge could not complain that he is having trouble pedalling against the tide.

The Shimano Alfine is an 11-speed rear hub which has the decided advantage of being able to put a total cover chain guard around the entire chain and SINGLE SPEED front ring and still be able to leap tall buildings in a single bound.

Now building this set of wheel would cost the better part of a thousand dollars and we're all a bunch of cheapskates.

But with bikes costing $5K+ I'm sure you could build the perfect commuter for half that amount.


Once again; *SOME PEOPLE PREFER THE CONVENIENCE OF BATTERY LIGHTS FOR THEIR OWN USES!*

If I had to spend $2,500.00 for a commuter bicycle I'd seriously look at a used car just for commuting.

Cheers


I don't recall forcing anything on you. Or do you simply object to opinions?


BUT you did NOT express an opinion. You said: On Sunday, March 5, 2017 at 1:56:13 PM UTC-5, wrote:
Since you people have been talking about lights I've been looking. Like sms I really don't like the idea of having normal batteries that wear out quickly or the idea of always keeping your battery on charge.

This means you need a bulb generator or a hub generator. The hub generator seems a good answer but they don't appear to make half of the power of a bulb generator."


You intaht case is not myself nor is it a lot of other people who prefer battery powered lights for whatever reasons thosepeople have.

Cheers
  #5  
Old March 6th 17, 01:08 AM posted to rec.bicycles.tech
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Posts: 1,482
Default More About Lights

On Sunday, March 5, 2017 at 1:34:33 PM UTC-8, Sir Ridesalot wrote:
On Sunday, March 5, 2017 at 2:26:07 PM UTC-5, wrote:
On Sunday, March 5, 2017 at 11:12:01 AM UTC-8, Sir Ridesalot wrote:
On Sunday, March 5, 2017 at 1:56:13 PM UTC-5, wrote:
Since you people have been talking about lights I've been looking. Like sms I really don't like the idea of having normal batteries that wear out quickly or the idea of always keeping your battery on charge.

This means you need a bulb generator or a hub generator. The hub generator seems a good answer but they don't appear to make half of the power of a bulb generator.

But that's a little hard to tell since they seem to have a great deal of trouble listing the output of the various dynamos.

You can get a 6 watt bulb generator but the hubs appear to all deliver 3 watts.

Now there are extremely efficient hubs that even Frank wouldn't have any trouble peddling in his old broken down and crippled state.

But when you look up the lights you find the same problem - you have a very difficult time finding power in and lumens out.

There are a few things that I really like the idea of in a commuter bike:

A front wheel hub generator - the German Schmidt which is extremely reliable and apparently is 78% efficient so Jorge could not complain that he is having trouble pedalling against the tide.

The Shimano Alfine is an 11-speed rear hub which has the decided advantage of being able to put a total cover chain guard around the entire chain and SINGLE SPEED front ring and still be able to leap tall buildings in a single bound.

Now building this set of wheel would cost the better part of a thousand dollars and we're all a bunch of cheapskates.

But with bikes costing $5K+ I'm sure you could build the perfect commuter for half that amount.

Once again; *SOME PEOPLE PREFER THE CONVENIENCE OF BATTERY LIGHTS FOR THEIR OWN USES!*

If I had to spend $2,500.00 for a commuter bicycle I'd seriously look at a used car just for commuting.

Cheers


I don't recall forcing anything on you. Or do you simply object to opinions?


BUT you did NOT express an opinion. You said: On Sunday, March 5, 2017 at 1:56:13 PM UTC-5, wrote:
Since you people have been talking about lights I've been looking. Like sms I really don't like the idea of having normal batteries that wear out quickly or the idea of always keeping your battery on charge.

This means you need a bulb generator or a hub generator. The hub generator seems a good answer but they don't appear to make half of the power of a bulb generator."


You intaht case is not myself nor is it a lot of other people who prefer battery powered lights for whatever reasons thosepeople have.

Cheers


Well, I didn't realize that English isn't your first language. So rather than me changing my comments I suggest that you learn English.
  #7  
Old March 6th 17, 01:03 AM posted to rec.bicycles.tech
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Posts: 1,482
Default More About Lights

On Sunday, March 5, 2017 at 11:32:51 AM UTC-8, Jeff Liebermann wrote:
On Sun, 5 Mar 2017 10:56:09 -0800 (PST), wrote:

But when you look up the lights you find the same problem - you
have a very difficult time finding power in and lumens out.


Hint: Measuring lumens is messy and expensive. Here's what it took
to verify lumens in 2014:
http://www.roadbikereview.com/reviews/2014-bike-lights-shootout-lumen-measurements
(I like the lumens/dollar bar graph).

For numbers and beam pattern photos, try:
https://www.bikelightdatabase.com
http://reviews.mtbr.com/2016-bike-lights-shootout-lumen-measurements
http://reviews.mtbr.com/2016-bike-lights-shootout-beam-patterns
http://road.cc/content/buyers-guide/212914-updated-your-guide-best-front-lights-cycling-beam-comparison-engine
http://www.roadbikereview.com/reviews/2014-bike-lights-shootout-tunnel-beam-patterns
There are others, but that's what I found in my bookmark collection.
There are also comparisons and tests on YouTube.

--
Jeff Liebermann

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


Thanks Jeff. These however all appear to be battery powered lights. We were sort of looking for lights that operated on the hub dynamo of 6V 3W or the Globe dynamo of 12V 6W or four times the power.

This is why the hub generator has so little drag.

  #8  
Old March 6th 17, 02:26 AM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 2,225
Default More About Lights

On Sun, 5 Mar 2017 16:03:30 -0800 (PST), wrote:

Thanks Jeff. These however all appear to be battery powered
lights. We were sort of looking for lights that operated on
the hub dynamo of 6V 3W or the Globe dynamo of 12V 6W or
four times the power.


Sorry, I thought you were still open to looking at battery powered
lights. Here's what I fished out of my bookmark dumpster. No reviews
and few tests, but some interesting dynamo graphs and numbers:
http://www.myra-simon.com/bike/dynotest.html
http://pilom.com/BicycleElectronics/DynamoCircuits.htm
http://www.eeweb.com/blog/extreme_circuits/power-mosfet-bridge-rectifier

This one is well worth reading (or skimming) and has quite a few test
results:
http://swhs.home.xs4all.nl/fiets/tests/verlichting/index_en.html

This is why the hub generator has so little drag.


Well, let's do some arithmetic. If your dynamo is rated at 3 watts,
and your lighting is rated at 70 lumens/watt, then the most you can
perhaps deliver is 210 lumens. 6 watts will get perhaps 420 lumens.
Usually, it's less as the losses accumulate. Rectification losses,
optical losses, heat degradation, and connector losses all conspire to
produce lower output.

You might find it useful to know how bright you want your light. For
that, you'll need a Lux meter. I have a Lutron LX-102 which works
nicely, and two junk meters I bought on eBay for sanity checks:
http://www.ebay.com/sch/i.html?_nkw=lux+meter
Get one that has a wide range. Lowest on mine is 1000 lux, and
highest range is 50,000 lux.

Find a dark night and an accomplice to operate the meter and send them
down the road to the farthest distance that you might want to
illuminate with your headlight. Use a headlight or flashlight to
light up that area. Have your accompli's take a reading. It will
probably be zero. Now, cut the distance in half and take a
measurement. It will be 2x as bright (lux) at half the distance or 4x
as bright at 1/4th the distance. Adjust the brightness for what it
would have been if the light meter was sufficiently sensitive.

Converting the brightness (lux) to luminous flux (lumens) requires
that you know the distance to the accomplice, and the illumination
angle. (1 lux = 1 lumen/square-meter)

The form below makes a mess of bad assumptions but is good enough for
a rough approximation:
https://www.ledrise.com/shop_content.php?coID=19
Once you know how many lumens you think you need, and have adjusted
for overly ambitious expectations, you can determine which lighting
technology is suitable.

Lets say you want to see 8 meters ahead and 20 degrees to each side
(or 40 degree conical beamwidth) at 20 lux, which is rather dim.
Plugging into the web page above, I get 485 lumens needed. You won't
be able to do that with a 3w dynamo, but might squeeze by with a 6w
and an oval shaped beam.


--
Jeff Liebermann

150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #9  
Old March 6th 17, 06:50 AM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 2,225
Default More About Lights

On Sun, 05 Mar 2017 17:26:21 -0800, Jeff Liebermann
wrote:

Find a dark night and an accomplice to operate the meter and send them
down the road to the farthest distance that you might want to
illuminate with your headlight. Use a headlight or flashlight to
light up that area. Have your accompli's take a reading. It will
probably be zero. Now, cut the distance in half and take a
measurement. It will be 2x as bright (lux) at half the distance or 4x
as bright at 1/4th the distance. Adjust the brightness for what it
would have been if the light meter was sufficiently sensitive.


No brain today. That should be half the distance equals 4 times as
bright and 1/4th the distance equals 16 times as bright.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #10  
Old March 6th 17, 07:04 AM posted to rec.bicycles.tech
James[_8_]
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Posts: 5,491
Default More About Lights

On 06/03/17 12:26, Jeff Liebermann wrote:

Well, let's do some arithmetic. If your dynamo is rated at 3 watts,
and your lighting is rated at 70 lumens/watt, then the most you can
perhaps deliver is 210 lumens. 6 watts will get perhaps 420 lumens.
Usually, it's less as the losses accumulate. Rectification losses,
optical losses, heat degradation, and connector losses all conspire to
produce lower output.


We know that a 3W dynamo is quite capable of delivering more power than
3W, once the bicycle speed increases. 6W from a 3W dynamo is quite
achievable, and the retardation torque drops off as speed increases too.

--
JS
 




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