Anybody use a Hub Generator

I have a Sturmey-Archer dyno hub on the front of my old BSA three speed, that has given good service for thirty-plus years. I can't say that it gives good light, (not like modern rechargeable lights,) but it has the advantage of always being on the bike and always working. It has never burned a bulb out. Though I did change the bulb once when I switched to a different head light.
 
Dunno about "other accessories" but they certanly produce enough power to run a 6V headlight & tail light combination,preferably focused LED's.
 
I tought about making my own. If you turn a small DC motor fast enough, it will produce current. How much???
 
On a Nov. trip to the bike shop I saw 2 Trek Cruisers ($450-500) with generators in the front hub.

The idea is it operates the automatic shifter....but I could have swore I saw the end of a white wire coming out the bottom of the front hub, which means there MUST be a use for excess current.

Searching, I found a review here:

http://www.autobloggreen.com/2007/04/06/check-out-the-trek-lime-automatic-shifting-bicycle/


The reviews in the comment section are about 50/50, but the comment most intriguing is #6

1) Where does the electricity go that is not used to shift?
Your not shifting all the time, sure there has to be a little bit used to sense when it needs to actually shift, but that shouldn't use up much and there's no battery on board to store any excess unused electricity.

2) How difficult would it be to put a battery charger in the seat?
There is a mention of storing an Apple Ipod in the seat. Apple sold over 100 million of those and is coming out with an phone. Not to mention every other brand cellphone, portable game, personal organizer, GPS, flashlight, laptop, etc. These all contain batteries that need to be recharged. I'd Co-Market the "Lime" with Apple and anyone else that would pick up half the advertising cost and let 3rd parties sell the chargers. A bike that changes colors, recharges your favorite toy and low maintance, How COOL is that!


The review has a link to the actual Trek site here:

EDIT: This link doesn't work, but leaving it up for search clues

http://www2.trekbikes.com/lime/?step=bikeMenu



another commenter put up a NuVinci blog report, (may or not be useful) so I'm sticking it here:

http://phil.veloblog.ch/post/7/333
 
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Okay, here's the link, but it must be one of those "movie" type websites, like that sorry Sun website, that takes a dialupper 10 mins. to load:

Thats why the above link didn't work, I guess. Somebody with better connections and more patience could check it out for info:

http://www.trekbikes.com/lime/
 
wiki search on "hub dynamo", the Trek must be this Shimano DH3N70/71 setup:

http://en.wikipedia.org/wiki/Hub_dynamo
Shimano offer a variety of hub dynamos under the Nexus brand, such as the DH-3N70 (also called DH-3N71), which is advertised as having significantly less drag than the Nexus NX-30. However, the Shimano hub dynamos generate more drag than the SON[citation needed]. Some of the Shimano units come with an automatic light-sensitive switch.
 
A small hub motor (used on E Bikes) works better as a generator, with a LOT more watts - a 200W motor at motored bike speeds can provide a good 75-100W.
 
A small hub motor (used on E Bikes) works better as a generator, with a LOT more watts - a 200W motor at motored bike speeds can provide a good 75-100W.

A nice small generator hooked up to the SBP jackshaft would be awesome with someone kind of clutch engagement to reduce drag when not needed.
 
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