Lights and reflectors the legal requirements


Maximum Pace
Oct 25, 2011
Setagaya, Tokyo
I want to get dynamo, too. Only problem for me is that I have too many bikes, and I know that once I have it on one, I'll want it on them all.
Yes. I have a dynamo hub on both of my bikes, with matching dynamo front light. My NFE also has a dynamo-operated rear light while the Bike Friday still uses a battery operated rear light (using Eneloop NiMH rechargeables). If you do significant night riding, a dynamo hub is the bee's knees. I even had a dynamo hub wheel built for one of my son's bikes, on the off chance that I might borrow it sometimes.

@joewein has the full, rectified and balanced setup for lighting and charging.
I no longer use my dynamo hub for charging. Back in the days I experimented with several different USB charger units imported from Germany. Some died, some fried buffer batteries or worse, my mobile phone! Limiting output voltage on fast descents can be a tricky business to get right for the developer of the hardware. This was probably exacerbated by the 20" wheels on my Bike Friday which result in 33% more RPMs at the same speed than with 700C or 650B.

Anyway, I am now using a 100 mAh Li-ion battery for keeping my phones (I usually carry two) and my GPS charged. It stores enough juice to keep all gadgets charged for a ride stretching over a complete two day weekend. If I were to do longer rides without any chance to recharge such as 1200 km brevets or multi-day touring totally off the grid then I might reconsider, but for now I am only using the dynamo hub for the lights, which use considerably more power than phones do and therefore are difficult to support with batteries.

Both of my bikes use Shutterprecision dynamo hubs and B&M Lumotec IQ Cyo lights (Premium on the NFE, N Plus on the BF). When I cycle at night I don't worry any more than if I was driving a car. On a 300 km brevet I ride in the dark for about 7 hours while on a 400 km brevet it's basically the whole night.


Maximum Pace
Dec 2, 2017
I bought a large Anker battery with 20,000 mAh and a smaller ~6,000 mAh one. The big one was not that much more expensive, but it is a lot, lot heavier whereas the smaller one is just a small, round cylinder. Unlike cheap rechargeable batteries, even the small Anker batteries have a fast charging port. (I noticed that the cheap battery I got is so weak, it doesn't even charge my lights.) 6,000 mAh is plenty for a day trip, enough to completely charge my lights and my phone with energy to spare.