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I wouldn't be too concerned but if I did run wiring internally, I'd cover it with wrap-around sleeving (link to McMaster-Carr but there's lots of sources) and put a self-fusing tape wrap at each end and one in the middle to keep it closed.
Outside? Small zip ties, trimmed neatly. If you're really worried about it, a wrap of self-fusing tape or sleeving around the wiring before securing it with the zip tie.
In thirty-odd years of motorcycling I've had one abraded wire and it wasn't internal or at a zip tie, it was where the cable for a heated grip rubbed against a flexible bit of body panel exposing copper and I caught that before it failed.