What is a good on road off road bicycle?

Batteries, either rechargeable or disposable, are often used to power electric bicycle lights. For bicycle touring, commuting or if managing your batteries is just too much of a nuisance, powering the lights with a electrical generator, or dynamo, may be a better option. Unlike batteries a dynamo lighting system has unlimited duration, but the maximum power output is relatively low (to some extent this is mitigated by good optics and slight overvolting of the lamp; a good dynamo nominally rated at 6 V is generally allowed to produce 7 V or so by its voltage limiting circuitry). In Germany it is illegal, for environmental reasons, to use lamps powered by disposable batteries except on the most lightweight cycles. This has stimulated the market for high quality dynamos such as B&M or Schmidt.