Hub generator
 

I am thinking of getting a german hub generator for when I buy my Giro 20 does any one use them on thier bents in here? and would they work on my old BLT halogen lights ?, or is not worth buying it at all? thanks

Study Peter White's material on lighting systems, including reviews of various types of dynamo hubs. The Schmidt hub is available for 16" and 20" wheels. At a dynamo's power output levels, you'll probably be happier with a modern LED light than with a halogen.

I am getting a SON built up for my Volae Expedition - still waiting for the rim to come in - hopefully this week. I am going to run a Solidlights 1203D LED light from the hub. You need a headlight designed to work with a dynohub - you can't just plug in a halogen light designed to run from a DC battery.

NiMH rechargeable batteries are a lot cheaper... :)

I have used NiMH rechargeables, but they have a number of problems:
- need to carry enough for your whole ride (could be 2 to 4 sets for an all night ride) that would be up to 16 AA batteries for one of my bikes
- they put out less voltage than alkaline batteries so lights are not as bright
- have to take the time to recharge them
- may not have them charged for a spur of the moment ride
- for multi-day events you have to deal with charging and spare batteries
- batteries are not happy in cold conditions and you'll need to replace more frequently
- they will have to be disposed of after a limited number of recharge cycles

A SON hub will last 20,000kms of riding and can then be economically refurbished and reused. If you do lots of night riding you can recoup the cost of a dyno hub. Less money up front is not necessarily cheaper.

Good points, but:
- Alkaline batteries don't output at 1.5V for a very long time
- Fast chargers can allow for a spur of the moment ride (although I read that the faster the charge, the lower the life expectancy of the batteries)
- Arent NiMH batteries supposed to work better in cold conditions? if low temps are a concern, you can use lithiums
- Sure they dont last forever, but the cost is recouped faster (compared to disposable batteries)
- Battery powered lights stay on when you're not moving

Your number of batteries for an all night ride is about right (same for me anyway), but I dont see how 16xAAs are a big problem to carry.

I didn't consider multi-day events, since I never do them.

What about the ongoing drag from the hub-generator? How do you measure that?

Personally I'd rather have a free-spinning hub and carry an extra set of batteries. LED lights these days are very efficient.

I use a 5Ah 14.4V NiMH bottle battery from batteryspace.com to drive my NiteRider Classic 12V halogen dual-beam headlamp (15W spot, 20W flood, or both) and two LED-array taillights. Even with all 35W blazing away it has enough burn time to get from home to office and back again (30 mile round trip) with some reserve for occasional errands along the way. I plug it into a smart charger every night.

I haven't found any LED headlamps that were bright enough to make me want to switch away from my 35 retina-scorching watts of halogen, though the new DiNotte Triple would likely hit the mark. But it's not worth (to me) the extra money to save the weight, since I already have a working system.

The SON hub dynamo might be able to provide enough power to drive something like the DiNotte Triple and some taillights, though I haven't done the math. I don't need it because I don't do overnight rides - I'm just a commuter going to work and back again.

This stuff is discussed in great detail on BikeCurrent. If you're interested, I suggest you check in there.

The drag is the sum of the load (bulb wattage) plus wiring and regulator inefficiencies. If the light is turned off the generator presents no drag.

are these are the solid lights your talking about ?? http://www.solidlights.co.uk/products/1203d.php

Here's a better answer than I gave earlier: an article (or pdf) in Vintage Bicycle Quarterly.

That's it. I have a bunch of pics of my mounting set up on my lazy randonneur blog Feb 9 & 10.

I have been snooping around your blog:D , Did you hook up the lights yet? and what's it like randonneuring on a recumbent ? , I have been looking through the Ontario randonneur site alot and want to start doing that one day cause I love riding at night under the stars and moon.

I'm still waiting on a rim to arrive at my LBS before I get to try out the 1203D.

I haven't done any brevets yet [first one is a 200K April 14th]. The snow is on its way out here in Canada so I should be riding my Volae again in a week or so. I have had it out for 100K rides and it is very comfortable and a pleasure to ride. My uphill speeds are quite a bit slower than on my DF bikes, but I haven't had much time to develop my recumbent muscles before winter hit. I expect to improve my climbing quite a lot, but I don't think I will be as fast as on DF bike. However, I simply wouldn't be able to ride 200K+ on any of my DF bikes without suffering quite a lot. If I was able to complete a 300K on my DF bike I would probably not be as fast as on my recumbent simply because I would have to stop more often and give my body a break. OTOH most randonnuers ride DF bikes.

The Ont Randos must start up around the same time as Alberta - early April. Definitely get out and ride the early season brevets. You'll have fun...:D Drop me a line a let me know how it goes.

My rim FINALLY arrived - cool the roads are clear as well. I should be able to get a good test in next week.

tell them to hurry and go for the test ride on Saturday or Sunday:)

hahahaha...best I can do is Wednesday evening - if they get the wheel built on time....:D