A few years ago when I built my first rando bike, I agonized over the choices and decided on a Shimano dynohub with a CYO headlight and dyno-powered taillight. For 2 SR series, PBP, and two 24-hour races it has been great - particularly not having any concern about battery life, changing batteries, or charging batteries.

I told myself I'd reconsider when it came time, and it's time. My new rando bike has a different wheelsize, so I'm at least re-lacing a new wheel. I'm sure there are better options this time around. Truth be told, I'd prefer all my watts be propelling me down the road.

Since this will be used for multiple nights of riding with no chance for recharging; runtime is a huge factor. Conditions will vary from urban to rural, riding all night long. I do typically have a small helmet-mount light to help read streetsigns and look around curves.

What kind of run-times are possible these days on a "see with" light in full-on mode?

That much battery capacity will be HEAVY, or use a lot of disposables. I think with those constraints, you would still be best off with a dynamo hub. I would suggest looking at the Shutter Precision dynamo's. Yes you will take a 6-7 watts penalty at night with the lights on, but during the day the Schmidt SON and Shutter Precision hubs will only draw only about a watt with the lights off.

All your Watts will be propelling you and the massive battery pack.

A Dinotte XML-3 tail with 4 cell battery pack (240g) has a run time of 5hrs at 50% power. So realistically to get say 30 hrs of runtime, you'll need 6-8 battery packs, and a total weight of ~2kg for batteries. Given the hassle of recharging multiple packs along with swapping mid-ride.

I'm normally a big advocate of battery lights, this is one case where hub power makes a lot more sense.

I agree that you're a good candidate for sticking with dynamo power.

Tail lights need a lot less power than headlights, so I think battery powered tail lights are fine, and there are many to choose from. Batteries in my tail lights last for months.

But have at least one dynamo powered headlight. They are very reliable, and I only see high quality dynamo powered headlights on the market.

Twin Schmidt E6 halogen headlights are a classic , secondary, gets turned on for descents.

crisp bright rectangle with surrounding light around it.. align the 2ndary to light, even further ahead ..

I have no use for the set I got because I cannot swing the travel to do those events,

and I'm Old and Slow.. PM me .. resale at wholesale cost..

Yeah, hauling massive battery packs up hills doesn't sound like fun.

Thanks for the input, it looks like for the longer brevets it's going to be dynamo power. fietsbob, thanks for the offer but I do already have a decent dynamo headlight. The CYO is not the very best but pretty good, not nearly as bright as some of the battery lights I see, but it gets the job done.

I might just give the Shutter Precision dynamo a try. They offered to give me one for the cost of shipping prior to PBP 2011, if I would write up a review. I eventually backed out, not wanting my brevet season to be jeopardized by an unproven unit.