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Old 12-06-17 | 04:20 PM
  #22  
Tourist in MSN
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Bikes: 1961 Ideor, 1966 Perfekt 3 Speed AB Hub, 1994 Bridgestone MB-6, 2006 Airnimal Joey, 2009 Thorn Sherpa, 2013 Thorn Nomad MkII, 2015 VO Pass Hunter, 2017 Lynskey Backroad, 2017 Raleigh Gran Prix, 1980s Bianchi Mixte on a trainer. Others are now gone.

Originally Posted by boomhauer
The drag is proportional to the number of magnets they have spinning around in there.
I believe the term is "reluctance", if memory serves.
No. When I said the following, that pretty much proves that if more power is consumed, then the drag is increased.

Originally Posted by Tourist in MSN
...
When I am off the bike, if I lift the front wheel off the ground and give it a spin it will keep spinning much longer if my light is turned off than if the light is turned on.....
The wheel spins for a shorter period of time when drag is increased, that drag is increased when the light is on.

*** ***

Originally Posted by gauvins
...
My perspective is that since efficiencies are essentially the same, total drag is the same, whether you have a high vs low output charger. It is only a matter of how drag will be distributed over the day. In my experience, batteries were fully charged within a couple of hours on a typical day, meaning that the charger had to deliver whatever wattage my phone would consume once fully charged, i.e. < 2W, A high power charger is more forgiving wrt power management. And drag wattage is very low anyway, and becomes meaningless when your speed goes down, climbing, and you want all of your few leg-generated watts to propel you up that nasty hill...
I pretty much agree with this.

I would add to that that if you had a lot of devices and a day of riding with most chargers was insufficient for your needs that your higher output charger might be beneficial.

I am talking in generalities here, there would of course be slight differences with different hardware, etc. (As an engineer, I of course have to add the disclaimer.)
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