hi all

i'm building a shimano alfine 11s road bike for dad, (gates belt drive), he's asked for the hub dynamo,

i was planning on running the cable for the rear light through the downtube, and through the left hand chainstay, using dura-ace DI2 grommets each end,
what hole size will i need for the grommets ?

for the fork, i don't yet feel confident with internal routing, so i was thinking of using an old SS spoke and making small U shaped loops to use with zip ties,
that is just one thought i've had, yet if there are any other ways anyone has used to good success, i'd really like to hear from you :)

btw the fork is to be lugged steel, with a disc brake, and the lights will be supernova, with the front mounting at the fork crown

many thanks

NBC