I have a battery light on my summer touring bike, It's OK because its light longer in the summer, often I dont need it..

I share it with my studded tire bike, which only got a couple days below 0C out here, so hub dynamo wheel investment does not pencil out..
batteries in my pocket, keeps it warm., cold batteries have a performance drop off..

.. and a hub dynamo wheels on my Brompton, and Bike Friday P. Llama .. these get daily use ..





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