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Old September 14th 17, 06:46 AM posted to rec.bicycles.tech
bob prohaska
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Posts: 102
Default 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



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