Is there an updated Dynotest somewhere?
 

On 14/09/17 01:37, Sepp Ruf wrote:
Tosspot wrote:

It's coupled to a European dynamo light

What light is that?

http://radtouren-magazin.com/wp-content/uploads/2017/02/Herrmans_hblackpro_9323.jpg
from
http://radtouren-magazin.com/11530/e-bike/test-e-bike-scheinwerfer

(Compared to the DC version shown in the test, the dynamo H-Black-Pro is
somewhat dimmer.) It doesn't really matter because the Herrmans optic is
annoyingly unrefined in either version. And, needless to say, it's a low
beam with a symmetrical cutoff, so it is certainly not producing a DRL beam
shape.

That's the light I commute on (dynamo) and it's find for forest tracks
at night. It has the DLR on by default (which means the rear is on
permanently. Nice light, and going into 3rd winter so actually seems
waterproof!

Is there an updated Dynotest somewhere?
 

Sepp Ruf wrote:

For Rob who might experience mental drag uphill from just having to see a
big, heavy, non-laminated hub slowly revolving in the front wheel, the
smallish Shimano DH-T780-1N, 1.5W 250mA class, might suffice[1] once he
grows sick of the Soubitez. Best price I see is 96 euros a pair from CNC
Hamburg on ebay, no overseas shipping available, though.
http://www.ebay.com/itm/253093811841

[1]
DRL does not require more than 100 lumens if you get the optics right.

It's a bit puzzling how folks seem to excuse poor design in dynamo hubs
when they're considerably more fanatic about optimizing every other part
of a bicycle.

In particular, the 3 watt standard is utterly archaic. Folks now are
starting to use dynamos to power electronics, and I suspect most would
opt for more than 3 watt lights if useful designs were available.

I still don't understand why high-end builders like Schmidt don't use
salient-pole armatures, which could be constructed from standard motor
laminations (instead of the custom clawpole monolith used now). That
would shorten the iron path dramatically, reducing reluctance, reduce
the length of copper, reducing resistance. The performance gains can
be traded for lighter weight, higher efficiency or higher power.
Every motor builder in the world does it that way, why not dyamo hub
builders? Maybe there _is_ a technical reason, but it certainly isn't
apparent to me. The use of incandescent bulbs may have set the tradition,
but it's certainly no reason to continue.

At this rate I won't "get sick" of the Soubitez, I'll wear it out.

bob prohaska

Is there an updated Dynotest somewhere?
 

On Thu, 14 Sep 2017 05:46:06 -0000 (UTC), bob prohaska
wrote:

Sepp Ruf wrote:

For Rob who might experience mental drag uphill from just having to see a
big, heavy, non-laminated hub slowly revolving in the front wheel, the
smallish Shimano DH-T780-1N, 1.5W 250mA class, might suffice[1] once he
grows sick of the Soubitez. Best price I see is 96 euros a pair from CNC
Hamburg on ebay, no overseas shipping available, though.
http://www.ebay.com/itm/253093811841

[1]
DRL does not require more than 100 lumens if you get the optics right.

It's a bit puzzling how folks seem to excuse poor design in dynamo hubs
when they're considerably more fanatic about optimizing every other part
of a bicycle.

In particular, the 3 watt standard is utterly archaic. Folks now are
starting to use dynamos to power electronics, and I suspect most would
opt for more than 3 watt lights if useful designs were available.

I still don't understand why high-end builders like Schmidt don't use
salient-pole armatures, which could be constructed from standard motor
laminations (instead of the custom clawpole monolith used now). That
would shorten the iron path dramatically, reducing reluctance, reduce
the length of copper, reducing resistance. The performance gains can
be traded for lighter weight, higher efficiency or higher power.
Every motor builder in the world does it that way, why not dyamo hub
builders? Maybe there _is_ a technical reason, but it certainly isn't
apparent to me. The use of incandescent bulbs may have set the tradition,
but it's certainly no reason to continue.

At this rate I won't "get sick" of the Soubitez, I'll wear it out.

bob prohask

Not to argue but why is the "clawpole armature" used in automotive
"alternators".
--
Cheers,

John B.

Is there an updated Dynotest somewhere?
 

bob prohaska wrote:
Sepp Ruf wrote:

For Rob who might experience mental drag uphill from just having to see a
big, heavy, non-laminated hub slowly revolving in the front wheel, the
smallish Shimano DH-T780-1N, 1.5W 250mA class, might suffice[1] once he
grows sick of the Soubitez. Best price I see is 96 euros a pair from CNC
Hamburg on ebay, no overseas shipping available, though.
http://www.ebay.com/itm/253093811841

[1]
DRL does not require more than 100 lumens if you get the optics right.

It's a bit puzzling how folks seem to excuse poor design in dynamo hubs
when they're considerably more fanatic about optimizing every other part
of a bicycle.

In particular, the 3 watt standard is utterly archaic. Folks now are
starting to use dynamos to power electronics, and I suspect most would
opt for more than 3 watt lights if useful designs were available.

I still don't understand why high-end builders like Schmidt don't use
salient-pole armatures, which could be constructed from standard motor
laminations (instead of the custom clawpole monolith used now). That
would shorten the iron path dramatically, reducing reluctance, reduce
the length of copper, reducing resistance. The performance gains can
be traded for lighter weight, higher efficiency or higher power.
Every motor builder in the world does it that way, why not dyamo hub
builders? Maybe there _is_ a technical reason, but it certainly isn't
apparent to me. The use of incandescent bulbs may have set the tradition,
but it's certainly no reason to continue.

At this rate I won't "get sick" of the Soubitez, I'll wear it out.

bob prohaska

Machine theory is a bit of a black art for me, but I suspect that the "less
optimized" magnetics in hub dynamos provides the extra leakage inductance
required to make it self regulate into a 12 ohm load. I fully agree that a
less well regulated output plus a switching regulator could work very well
with modern electronics.

Is there an updated Dynotest somewhere?
 

John B. wrote:
:On Thu, 14 Sep 2017 05:46:06 -0000 (UTC), bob prohaska
wrote:

:
:I still don't understand why high-end builders like Schmidt don't use
:salient-pole armatures, which could be constructed from standard motor
:laminations (instead of the custom clawpole monolith used now). That
:would shorten the iron path dramatically, reducing reluctance, reduce
:the length of copper, reducing resistance. The performance gains can
:be traded for lighter weight, higher efficiency or higher power.
:Every motor builder in the world does it that way, why not dyamo hub
:builders? Maybe there _is_ a technical reason, but it certainly isn't
:apparent to me. The use of incandescent bulbs may have set the tradition,
:but it's certainly no reason to continue.

:Not to argue but why is the "clawpole armature" used in automotive
:"alternators".

Because saliant pole alternators with the outputs required are
physically larger and heavier than the Lundell style.



--
sig 30

Is there an updated Dynotest somewhere?
 

Tosspot wrote:
On 14/09/17 01:37, Sepp Ruf wrote:
Tosspot wrote:

It's coupled to a European dynamo light

What light is that?

http://radtouren-magazin.com/wp-content/uploads/2017/02/Herrmans_hblackpro_9323.jpg
from
http://radtouren-magazin.com/11530/e-bike/test-e-bike-scheinwerfer

(Compared to the DC version shown in the test, the dynamo H-Black-Pro is
somewhat dimmer.) It doesn't really matter because the Herrmans optic is
annoyingly unrefined in either version. And, needless to say, it's a low
beam with a symmetrical cutoff, so it is certainly not producing a DRL beam
shape.

That's the light I commute on (dynamo) and it's find for forest tracks
at night. It has the DLR on by default (which means the rear is on
permanently. Nice light, and going into 3rd winter so actually seems
waterproof!

Very early adopter there! Don't you get a gap between the wheel and where
the large bottom patch of light hits the ground? I don't like that when
riding offroad.

I appreciate the lamp's concept though and hope they'll eventually come
around to using some nicer LED and putting more effort into smoothing out
the intensity and color transitions.

Is there an updated Dynotest somewhere?
 

On 9/14/2017 10:26 AM, Ralph Barone wrote:
bob prohaska wrote:
Sepp Ruf wrote:

For Rob who might experience mental drag uphill from just having to see a
big, heavy, non-laminated hub slowly revolving in the front wheel, the
smallish Shimano DH-T780-1N, 1.5W 250mA class, might suffice[1] once he
grows sick of the Soubitez. Best price I see is 96 euros a pair from CNC
Hamburg on ebay, no overseas shipping available, though.
http://www.ebay.com/itm/253093811841

[1]
DRL does not require more than 100 lumens if you get the optics right.

It's a bit puzzling how folks seem to excuse poor design in dynamo hubs
when they're considerably more fanatic about optimizing every other part
of a bicycle.

In particular, the 3 watt standard is utterly archaic. Folks now are
starting to use dynamos to power electronics, and I suspect most would
opt for more than 3 watt lights if useful designs were available.

I still don't understand why high-end builders like Schmidt don't use
salient-pole armatures, which could be constructed from standard motor
laminations (instead of the custom clawpole monolith used now). That
would shorten the iron path dramatically, reducing reluctance, reduce
the length of copper, reducing resistance. The performance gains can
be traded for lighter weight, higher efficiency or higher power.
Every motor builder in the world does it that way, why not dyamo hub
builders? Maybe there _is_ a technical reason, but it certainly isn't
apparent to me. The use of incandescent bulbs may have set the tradition,
but it's certainly no reason to continue.

At this rate I won't "get sick" of the Soubitez, I'll wear it out.

bob prohaska

Machine theory is a bit of a black art for me, but I suspect that the "less
optimized" magnetics in hub dynamos provides the extra leakage inductance
required to make it self regulate into a 12 ohm load. I fully agree that a
less well regulated output plus a switching regulator could work very well
with modern electronics.

Is it feasible to use a switching regulator when you've got as much
inductance as a typical hub dynamo? I'd have thought that causes problems.

But then, I'm not an EE.

--
- Frank Krygowski

Is there an updated Dynotest somewhere?
 

On 9/14/2017 1:46 AM, bob prohaska wrote:
Sepp Ruf wrote:

For Rob who might experience mental drag uphill from just having to see a
big, heavy, non-laminated hub slowly revolving in the front wheel, the
smallish Shimano DH-T780-1N, 1.5W 250mA class, might suffice[1] once he
grows sick of the Soubitez. Best price I see is 96 euros a pair from CNC
Hamburg on ebay, no overseas shipping available, though.
http://www.ebay.com/itm/253093811841

[1]
DRL does not require more than 100 lumens if you get the optics right.

It's a bit puzzling how folks seem to excuse poor design in dynamo hubs
when they're considerably more fanatic about optimizing every other part
of a bicycle.

In particular, the 3 watt standard is utterly archaic. Folks now are
starting to use dynamos to power electronics, and I suspect most would
opt for more than 3 watt lights if useful designs were available.

Well, dynamos are not limited to 3 Watts. As James and others have
discussed, they'll put out more power if presented with bigger loads,
i.e. more resistance. They're essentially constant current devices. I
used to occasionally drive two halogen headlamps from my Soubitez roller
dynamo. Others do it with hub dynos. (It doesn't work well with a bottle
dyno, though, because the smaller drive roller is more prone to slipping.)

Second, despite the current fashion for mega-lumen lights, I've seen no
evidence that road cyclists need them, and I've seen the disadvantages.
IME, a good B&M LED headlight lights up a stop sign nearly 1/4 mile way.
It also illuminates the road very well; and with ever-improving LEDs,
the current models are probably better than the ones I own.

And it's a little ironic that the mega-lumen fans choose to ignore poor
optical design in their headlights, leading to inferior illumination
while blinding others. I think that's a bigger problem than a few
percent less theoretical efficiency in the dynamo.

Finally, there are devices which will power a phone or a GPS unit from a
hub dyno. Personally, I'd prefer to limit people from (say) playing
their stereo speakers while they ride!
At this rate I won't "get sick" of the Soubitez, I'll wear it out.

I've got two that are working very well. They're decades old. One was a
gift, from a friend who ripped out its output wire. A little solder
fixed that.

--
- Frank Krygowski

Is there an updated Dynotest somewhere?
 

Frank Krygowski writes:

On 9/14/2017 10:26 AM, Ralph Barone wrote:
bob prohaska wrote:
Sepp Ruf wrote:

For Rob who might experience mental drag uphill from just having to see a
big, heavy, non-laminated hub slowly revolving in the front wheel, the
smallish Shimano DH-T780-1N, 1.5W 250mA class, might suffice[1] once he
grows sick of the Soubitez. Best price I see is 96 euros a pair from CNC
Hamburg on ebay, no overseas shipping available, though.
http://www.ebay.com/itm/253093811841

[1]
DRL does not require more than 100 lumens if you get the optics right.

It's a bit puzzling how folks seem to excuse poor design in dynamo hubs
when they're considerably more fanatic about optimizing every other part
of a bicycle.

In particular, the 3 watt standard is utterly archaic. Folks now are
starting to use dynamos to power electronics, and I suspect most would
opt for more than 3 watt lights if useful designs were available.

I still don't understand why high-end builders like Schmidt don't use
salient-pole armatures, which could be constructed from standard motor
laminations (instead of the custom clawpole monolith used now). That
would shorten the iron path dramatically, reducing reluctance, reduce
the length of copper, reducing resistance. The performance gains can
be traded for lighter weight, higher efficiency or higher power.
Every motor builder in the world does it that way, why not dyamo hub
builders? Maybe there _is_ a technical reason, but it certainly isn't
apparent to me. The use of incandescent bulbs may have set the tradition,
but it's certainly no reason to continue.

At this rate I won't "get sick" of the Soubitez, I'll wear it out.

bob prohaska

Machine theory is a bit of a black art for me, but I suspect that the "less
optimized" magnetics in hub dynamos provides the extra leakage inductance
required to make it self regulate into a 12 ohm load. I fully agree that a
less well regulated output plus a switching regulator could work very well
with modern electronics.

Is it feasible to use a switching regulator when you've got as much
inductance as a typical hub dynamo? I'd have thought that causes
problems.

Happens all the time. Google "h-bridge", and notice all those diodes in
parallel with the switching components, allowing current always to
continue to circulate through some path. Typically the diodes are
in the same package as the switching component, eg MOSFET.



--

Is there an updated Dynotest somewhere?
 

On 9/14/2017 4:02 PM, jbeattie wrote:

As for dynos, I have to re-wire my mood light and get it up and running, maybe buy a bar mount since I no longer have a through-hole in my fork crown (such are modern CF forks on a disc bike -- and I'm not going to drill CF).

That sounds to me like a big disadvantage of a CF fork: the lack of a
mounting hole for a light, a front rack, or anything else.

I don't much like bike headlights at handlebar height. ISTM I get much
better illumination of the road when the headlight's about 24" to 28"
above the road. And it doesn't interfere with my handlebar bag (or
vice-versa) nor by packages in a front basket, etc. Also, less chance of
glare in my eyes.

--
- Frank Krygowski