Originally Posted by Aznman

There are 3 main types of dynamos: bottle dynamo, dynohub and roller dynamo.
All of them have severe disadvantages.

Dynohubs are often the most expensive and you would be required to buy specialized wheels.

Bottle Dynamos are loud, can slip and can cause tyre wear.

It is very easy to cause Roller Dynamos to malfunction because they are most exposed to dirt and mud.

I'm curious as to why there aren't any better options by now (the year 2013).
Are Contactless-Magnetic Dynamos any good? What about Dynamos that go on the chain?
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