Tape, 3M electrical, and Zip ties ..
WB Bicycle Gallery: Robert Clark's Koga Miyata WTR
tail light follows the gear cable , downtube, Front derailleur to bb, then along chainstay,
then up rack strut.. to rack Mounted tail light
Or glued inside rear mudguard.. (the Koga WTR has grommets to use the foil layer in the SKS Mudguards as a conductor )
My Dynamo hub has twin lead , as they are Alternators , 80s The Old higher drag Bottle dynamos , used Frame ground,
But they were Bulbs [2.4w+0.6w] not LEDs then..
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