I'm sorry - I just don't understand this comment. A dynamo light, to my knowledge, is nothing more than a light that does not need a battery. Quick searches show plenty of different dynamo lights on the market with different beam patterns. Wouldn't Day Safety just be akin to selecting the appropriate light? From my reading, dynamo lights are able to produce as much lumen as battery operated ones - are they not?

When it comes to dynamos, I think one of my questions to ppl who swear by them is if you feel a difference in the ride having the extra dynamo in the hub, vs a regular wheel. Is the drag, or the extra energy used to power the dynamo something you feel? Obviously, there is some extra energy that is required to power a dynamo vs a battery light, but is it even significant/a factor?

When it comes to Day Safety, how many people actually ride with lights on? There is a bike sharing program here (Bixi) that have dynamo front mounted flashing leds that are always on, but short of them, I don't think I have seen any cyclists in town ride with running daytime lights. Does it really make a difference?

Thanks!

Eric