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From: Frank Krygowski <frkrygow@sbcglobal.net>
Newsgroups: rec.bicycles.tech
Subject: Re: bike light optics
Date: Wed, 10 Apr 2024 12:36:37 -0400
Organization: A noiseless patient Spider
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On 4/10/2024 7:06 AM, Rolf Mantel wrote:
> 
> Cheap hub dynamoes have a rolling resistance in the order of 15W to 
> generate 3W.  A good hub dynamo can probably get those 12W out of a 
> mechanical resistance in the order of 20W.

Wow. I wasn't aware that any hub dynamos were that inefficient. Can you 
say which brands those are?

-- 
- Frank Krygowski