Most builders like using the factory style fitting for traditional looks and because it has a screen built into it to keep larger particles out of your engine.
Steel : 1 1/8" Diameter
Aluminum 1 1/4" Diameter.
There is a 2-10 wk production time for our custom hand made goods like our Galaxy Grips, PLUG WIRES, Pegs, Engine/Magneto/Fork Covers, etc. Production time varies depending on shop demands.