My concern would be ingress of dirt and moisture causing corrosion.

Martin P

Make it such that the headstock can not be rotated full circle? Many 'homebrew' wind turbines have no moving connections – they rely on the wind not winding up the output leads very much, thus allowing the operator to occasionally unwind any twist in the cables through the bottom of the tower before the twist becomes excessive. You would only then need some multistrand flexible wires.

Sliprings are also used on turbines, but tend to be rather larger than a bicycle tube! Automotive alternators use a smallish slipring arrangement for exciting current for the rotor. Spark ignition engines use carbon contact with brass for the distributor rotor connection for the high tension spark energy.

You might think about the horn button within the steering wheel of some cars, although they are a rather intermittent piece of kit. Morris Minor comes to mind as an example.

There have been many bicycles made with front wheel dynamos, over the years. Surely there must be some around that you could investigate. Enquiring on a bicycle type forum may yield some precise explanations of the usual methods.

Hope that helps.

If the dynamo is on the front wheel, and the light turns with the handlebars as usual, then you'd need 2 sets of slip rings. All getting a bit iffy. Can you mount a bit of small bore tube from the top of the forks to the handlebar stem, parallel to the steering head but turns with forks, and run the wire up that

My bike has a dynamo on the rear wheel, the light mounted on the handle bar, one wire, and frame return, so the return is through the bearings for the steering, works ok for me.

Ian S C