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-   -   SIX thousand and FIVE hundred lumens !!!!!!!!!! (http://www.cyclebanter.com/showthread.php?t=256494)

[email protected] October 1st 18 11:14 PM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
http://reviews.mtbr.com/magicshine-l...2018-interbike

The beloved Magicshine brings us what we finally need in bike lights. Thanks to all the gods. 6500 lumens! I think you can have either 5000 or 1500 or all 6500 lumens. Thankfully now we will not only be able to blind everyone else on the road or trail, but we can now cause their eyeballs to burst into flames and maybe hopefully their heads will also explode. Yeah!!!!!!

I don't know why "sms" did not report this in his post about Interbike. This has to be the most important thing to ever come from Interbike. He is letting us down.

Here is the post from the article:
"This latest offering from Magicshine incorporates everything they have learned about MTB lights over the years. The Monteer 6500 is MTB headlight designed for the most serious mountain biking enthusiasts, downhill racers and those who want nothing less than professional grade lighting system that can outshine the landing light on a passenger airliner.
A max actual output of 6500 lumens is cranked out by 3x CREE XHP 50.2 and 2x XM-L2 LEDs. Like the Eagle series MTB headlights, Monteer 6500 is designed with multiple beam patterns modes, the XHP50.2 will put out a max of 5000 lumens of flood light, while the bottom row of XM-L2s shoots into the distance with up to 1500 lumens."

It even has "CREE XHP and XM-L2 LEDs". So you know its got to be great. I bet it even meets or exceeds that German bicycle light standard.

Jeff Liebermann October 2nd 18 02:29 AM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
On Mon, 1 Oct 2018 15:14:18 -0700 (PDT), "
wrote:

http://reviews.mtbr.com/magicshine-l...2018-interbike


A max actual output of 6500 lumens is cranked out by 3x CREE XHP 50.2
and 2x XM-L2 LEDs. Like the Eagle series MTB headlights, Monteer 6500
is designed with multiple beam patterns modes, the XHP50.2 will put
out a max of 5000 lumens of flood light, while the bottom row of XM-L2s
shoots into the distance with up to 1500 lumens."


Only $350.
https://magicshine.us/product/monteer-6500-mtb-headlight/
"Six cell battery pack uses super high capacity 18650 cells
for a 10500 mAh total."

Ok, let's do the math.

Cree XHP 50.2 LED specs:
https://www.cree.com/led-components/products/xlamp-leds-arrays/xlamp-xhp50-2
https://www.cree.com/led-components/media/documents/ds-XHP502.pdf
The LED can be wired for either 6 or 12V.

If I use an initial voltage of the cells at 3.85V, 3 cells = 11.6V,
which is close to the maximum operating voltage and the end of the
graph on Pg 8. At 11.6V, it draws 1.5 amps per LED and produces 180%
of rated output (Pg 9) or:
1.8 * 1000 lumens @85C = 1800 lumens
Three of these LED's will produce a total of 5,400 lumens. Close
enough to the spec methinks.

Cree XM-L2 LED specs:
https://www.cree.com/led-components/products/xlamp-leds-discrete/xlamp-xm-l2
https://www.cree.com/led-components/media/documents/XLampXML2.pdf
My guess(tm) is that these are running on one cell with a series
current regulator. At 3.85V/cell, the current could be set to
anywhere. So, doing this backwards, in order to produce 750 lumens
per LED, each LED would need to draw:
750 / 280 = 268% of rated output
From the graph on Pg 6, that requires 2.3 amps, which is getting a bit
close to the absolute max of 3.0A/LED. Total drain for both XM-L2
LED's is 4.6 amps.

Total current with all the LED's on is:
4.5A = 4.6A = 9.1 amps
Total dissipation is:
(11.6v * 4.5A) + (3.85v * 4.6A) = 71 watts

Let's see how long it will run at full power.
"Burn time ranges from 1.2H to 82H depending on modes"
I'll assume the best 2200 ma-hr cells. That would be:
3.85v * 2.2amp-hrs * 6 cells = 50.8 watt-hrs
which means the battery will last:
71 watts / 50.8 watt-hrs = 1.4 hrs
That also works as advertised.

The LED's can (probably) deliver the specified 6500 lumens total, but
the 71 watts of heat produced by the LED's will need to be radiated or
conducted somewhere. I don't see any cooling system on the package.
Building it out of mostly aluminum doesn't work without some kind of
air flow:
"To maximize heat dissipating potential, light housing has
been redesigned with hard anodized aluminum which covers
almost the entire light body."
Swell, no fins to increase surface area.

Let's see what the package can do as a heat sink.
Latent heat for aluminum is 0.900 Joules/gm-K.
The light weighs 142 grams, which I'll assume is mostly aluminum.
The light dissipates 71 watts with all the LED's turned on.
I would guess that 75C would be uncomfortably warm for both the
electronics and the bicycle rider. That's a temp rise of 50C (50K).
Joules = Watts * seconds = 71 watts * seconds. Therefo
0.900 = 71 * seconds / (142 * 50)
Time(sec) = 900 seconds = 15 min
Not too horrible. One has 15 minutes of full brightness lighting, in
still air, before the LED's burn your hand or cause a thermal
shutdown.

When there's air flow, there will be more cooling and therefore take
longer to get hot.
The dimensions are 72 * 42 * 44 mm. Surface area is roughly:
(2 * (72*42/2)) + (2 * (42*44)) + (44 * 72)
3,000 + 3,700 + 3,200 = 9,900 mm^2
I'll finish this later as I need to do something else right now.

In my never humble opinion, the specs are quite real, but I have my
doubts about the ability the aluminum heat sink to remove the heat
produced. It's going to get very hot running at full power.

I bet it even meets or exceeds that German bicycle light standard.


Probably true because StVZO only sets the minimum requirements.
However if the spec has a maximum output, so as not to blind oncoming
traffic, it would probably fail. There was a proposal to limit
brigtness to 2.0 lux at 10 meters at eye level to reduce blinding
oncoming drivers and riders, but I don't know if that was added.
A bit of StVZO analysis:
https://swhs.home.xs4all.nl/fiets/tests/verlichting_analyse/verkeersregels/de_stvzo/index_en.html


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

Emanuel Berg[_2_] October 2nd 18 03:18 AM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
Jeff Liebermann wrote:

Ok, let's do the math.


I put a flashlight to the handlebars the other
day with re-openable cable ties. It seems to
work OK, a pretty solid fix. I cut the cable
ties with a combination plier so it looks neat
as well.

The flashlight is 3*AAA batteries with
9 diodes. How many lumens is that, do
you think?

I think I should get a proper bicycle light
soon tho.

--
underground experts united
http://user.it.uu.se/~embe8573

Frank Krygowski[_4_] October 2nd 18 03:35 AM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
On 10/1/2018 6:14 PM, wrote:
http://reviews.mtbr.com/magicshine-l...2018-interbike

The beloved Magicshine brings us what we finally need in bike lights. Thanks to all the gods. 6500 lumens!


6500 lumens? But... but... is that safe enough?

--
- Frank Krygowski

Frank Krygowski[_4_] October 2nd 18 03:37 AM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
On 10/1/2018 10:18 PM, Emanuel Berg wrote:
Jeff Liebermann wrote:

Ok, let's do the math.


I put a flashlight to the handlebars the other
day with re-openable cable ties. It seems to
work OK, a pretty solid fix. I cut the cable
ties with a combination plier so it looks neat
as well.

The flashlight is 3*AAA batteries with
9 diodes. How many lumens is that, do
you think?

I think I should get a proper bicycle light
soon tho.


One person who posts here spent years claiming that super-bright LED
flashlights were better than bike headlights.

Eventually, for Christmas I was given such a flashlight. It was bright
enough that as I drove a freeway on a dark night, it clearly illuminated
freeway signs overhead.

But it was still a terrible bike headlight. You need more than
brightness. You need proper optics, designed for the road. A circular
beam cannot do that.

--
- Frank Krygowski

John B. Slocomb October 2nd 18 03:50 AM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
On Mon, 1 Oct 2018 22:37:58 -0400, Frank Krygowski
wrote:

On 10/1/2018 10:18 PM, Emanuel Berg wrote:
Jeff Liebermann wrote:

Ok, let's do the math.


I put a flashlight to the handlebars the other
day with re-openable cable ties. It seems to
work OK, a pretty solid fix. I cut the cable
ties with a combination plier so it looks neat
as well.

The flashlight is 3*AAA batteries with
9 diodes. How many lumens is that, do
you think?

I think I should get a proper bicycle light
soon tho.


One person who posts here spent years claiming that super-bright LED
flashlights were better than bike headlights.

Eventually, for Christmas I was given such a flashlight. It was bright
enough that as I drove a freeway on a dark night, it clearly illuminated
freeway signs overhead.

But it was still a terrible bike headlight. You need more than
brightness. You need proper optics, designed for the road. A circular
beam cannot do that.


Come now, a flashlight works perfectly well ... just ride slower :-)
--

Cheers,

John B.

Jeff Liebermann October 2nd 18 06:40 AM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
On Tue, 02 Oct 2018 04:18:35 +0200, Emanuel Berg
wrote:

Jeff Liebermann wrote:

Ok, let's do the math.


I put a flashlight to the handlebars the other
day with re-openable cable ties. It seems to
work OK, a pretty solid fix. I cut the cable
ties with a combination plier so it looks neat
as well.

The flashlight is 3*AAA batteries with
9 diodes. How many lumens is that, do
you think?


Not enough info. Measure the current drain from the battery and I'll
give you a good guess(tm). I just happen to have a similar flashlight
handy, so I measured mine at about 160 ma. At 4.5V, that's 720 mw.
Generic T1(3mm) white LED's typically have an efficacy of about 20
lumens/watt. So the output would be:
0.720 watts * 20 lumens/watt = 14 lumens
I did a quick double check with my lux meter and measured 16 lumens.

Here's how it's done:
https://groups.google.com/d/msg/rec.bicycles.tech/UJdJQFTDgl8/NgOZUloVCwAJ
I was going to turn it into a web page, but after the rather
discouraging response I got from this newsgroup and two other forums,
I decided I had better things to do.

AAA Alkaline cells run about 900 ma-hr capacity, so at 720 ma, you get
maybe 1.3 hrs of operation.

I think I should get a proper bicycle light
soon tho.


Yep, good idea:
http://www.learnbydestroying.com/jeffl/pics/bicycles/slides/bicycle-flashlight.html

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

Sepp Ruf October 2nd 18 03:09 PM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
Jeff Liebermann wrote:
On Mon, 1 Oct 2018, " wrote:

http://reviews.mtbr.com/magicshine-l...2018-interbike


JFTR, that's not an actual review, it's "sponsored content."

A max actual output of 6500 lumens is cranked out by 3x CREE XHP 50.2
and 2x XM-L2 LEDs. Like the Eagle series MTB headlights, Monteer 6500
is designed with multiple beam patterns modes, the XHP50.2 will put
out a max of 5000 lumens of flood light, while the bottom row of XM-L2s
shoots into the distance with up to 1500 lumens."


Only $350.
https://magicshine.us/product/monteer-6500-mtb-headlight/
"Six cell battery pack uses super high capacity 18650 cells
for a 10500 mAh total."

Ok, let's do the math.


[tech calculations snipped]

In my never humble opinion, the specs are quite real, but I have my
doubts about the ability the aluminum heat sink to remove the heat
produced. It's going to get very hot running at full power.


Even on full power, the rather primitive
http://www.magicshine.com/wp-content/uploads/2018/07/MONTEER-6500-r-13-1.jpg
20 & 30 degrees beam delivers only half the 55,000 cd punch of the similar
looking Lupine Alpha, the latter being three times as expensive, though.
Nowhere close to an airliner landing beam's candlepower, of course, in
contrast to what is purported by Francis Cashedo's marketing hyperbole.

I bet it even meets or exceeds that German bicycle light standard.


And I doubt it would even meet the optical part of the simpler high-beam
standard.

Probably true because StVZO only sets the minimum requirements.
However if the spec has a maximum output, so as not to blind oncoming
traffic, it would probably fail. There was a proposal to limit
brigtness to 2.0 lux at 10 meters at eye level to reduce blinding
oncoming drivers and riders, but I don't know if that was added.


Decades ago, due to the introduction of those crazy bright, 36 lm, 2.4 W
halogen bulbs. The previous limit was 0.7 lx.

A bit of StVZO analysis:

https://swhs.home.xs4all.nl/fiets/tests/verlichting_analyse/verkeersregels/de_stvzo/index_en.html


No offense, but I'd characterize that as some facts and analysis, more
unrestrained interpretation and speculation, swamped in a stream of
consciousness, muddled by a lack of legal logic, trilingual challenges,
unfamiliarity with technical concepts and comparable automotive standards.
Worst of all, it's unlikely to get better by adding yet another source of
information or correction.

JBeattie October 2nd 18 05:29 PM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
On Tuesday, October 2, 2018 at 7:09:13 AM UTC-7, Sepp Ruf wrote:
Jeff Liebermann wrote:
On Mon, 1 Oct 2018, " wrote:

http://reviews.mtbr.com/magicshine-l...2018-interbike


JFTR, that's not an actual review, it's "sponsored content."

A max actual output of 6500 lumens is cranked out by 3x CREE XHP 50.2
and 2x XM-L2 LEDs. Like the Eagle series MTB headlights, Monteer 6500
is designed with multiple beam patterns modes, the XHP50.2 will put
out a max of 5000 lumens of flood light, while the bottom row of XM-L2s
shoots into the distance with up to 1500 lumens."


Only $350.
https://magicshine.us/product/monteer-6500-mtb-headlight/
"Six cell battery pack uses super high capacity 18650 cells
for a 10500 mAh total."

Ok, let's do the math.


[tech calculations snipped]

In my never humble opinion, the specs are quite real, but I have my
doubts about the ability the aluminum heat sink to remove the heat
produced. It's going to get very hot running at full power.


Even on full power, the rather primitive
http://www.magicshine.com/wp-content/uploads/2018/07/MONTEER-6500-r-13-1.jpg
20 & 30 degrees beam delivers only half the 55,000 cd punch of the similar
looking Lupine Alpha, the latter being three times as expensive, though.
Nowhere close to an airliner landing beam's candlepower, of course, in
contrast to what is purported by Francis Cashedo's marketing hyperbole.

I bet it even meets or exceeds that German bicycle light standard.


And I doubt it would even meet the optical part of the simpler high-beam
standard.

Probably true because StVZO only sets the minimum requirements.
However if the spec has a maximum output, so as not to blind oncoming
traffic, it would probably fail. There was a proposal to limit
brigtness to 2.0 lux at 10 meters at eye level to reduce blinding
oncoming drivers and riders, but I don't know if that was added.


Decades ago, due to the introduction of those crazy bright, 36 lm, 2.4 W
halogen bulbs. The previous limit was 0.7 lx.

A bit of StVZO analysis:

https://swhs.home.xs4all.nl/fiets/tests/verlichting_analyse/verkeersregels/de_stvzo/index_en.html


No offense, but I'd characterize that as some facts and analysis, more
unrestrained interpretation and speculation, swamped in a stream of
consciousness, muddled by a lack of legal logic, trilingual challenges,
unfamiliarity with technical concepts and comparable automotive standards.
Worst of all, it's unlikely to get better by adding yet another source of
information or correction.


StVZO are job-killing regulations. Markets should be allowed to regulate light output. Die globalists, die!
https://www.brooksengland.com/media/...1638b377e8.jpg


-- Jay Beattie.

AMuzi October 2nd 18 06:09 PM

SIX thousand and FIVE hundred lumens !!!!!!!!!!
 
On 10/2/2018 11:29 AM, jbeattie wrote:
On Tuesday, October 2, 2018 at 7:09:13 AM UTC-7, Sepp Ruf wrote:
Jeff Liebermann wrote:
On Mon, 1 Oct 2018, " wrote:

http://reviews.mtbr.com/magicshine-l...2018-interbike


JFTR, that's not an actual review, it's "sponsored content."

A max actual output of 6500 lumens is cranked out by 3x CREE XHP 50.2
and 2x XM-L2 LEDs. Like the Eagle series MTB headlights, Monteer 6500
is designed with multiple beam patterns modes, the XHP50.2 will put
out a max of 5000 lumens of flood light, while the bottom row of XM-L2s
shoots into the distance with up to 1500 lumens."

Only $350.
https://magicshine.us/product/monteer-6500-mtb-headlight/
"Six cell battery pack uses super high capacity 18650 cells
for a 10500 mAh total."

Ok, let's do the math.


[tech calculations snipped]

In my never humble opinion, the specs are quite real, but I have my
doubts about the ability the aluminum heat sink to remove the heat
produced. It's going to get very hot running at full power.


Even on full power, the rather primitive
http://www.magicshine.com/wp-content/uploads/2018/07/MONTEER-6500-r-13-1.jpg
20 & 30 degrees beam delivers only half the 55,000 cd punch of the similar
looking Lupine Alpha, the latter being three times as expensive, though.
Nowhere close to an airliner landing beam's candlepower, of course, in
contrast to what is purported by Francis Cashedo's marketing hyperbole.

I bet it even meets or exceeds that German bicycle light standard.


And I doubt it would even meet the optical part of the simpler high-beam
standard.

Probably true because StVZO only sets the minimum requirements.
However if the spec has a maximum output, so as not to blind oncoming
traffic, it would probably fail. There was a proposal to limit
brigtness to 2.0 lux at 10 meters at eye level to reduce blinding
oncoming drivers and riders, but I don't know if that was added.


Decades ago, due to the introduction of those crazy bright, 36 lm, 2.4 W
halogen bulbs. The previous limit was 0.7 lx.

A bit of StVZO analysis:

https://swhs.home.xs4all.nl/fiets/tests/verlichting_analyse/verkeersregels/de_stvzo/index_en.html


No offense, but I'd characterize that as some facts and analysis, more
unrestrained interpretation and speculation, swamped in a stream of
consciousness, muddled by a lack of legal logic, trilingual challenges,
unfamiliarity with technical concepts and comparable automotive standards.
Worst of all, it's unlikely to get better by adding yet another source of
information or correction.


StVZO are job-killing regulations. Markets should be allowed to regulate light output. Die globalists, die!
https://www.brooksengland.com/media/...1638b377e8.jpg


-- Jay Beattie.


Nice try but it's not safe. No Federally mandated CPSC wheel
reflectors. Anything could happen!

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971




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