The Bafang BBS02 runs a fat “harness cable” from the motor to the four handlebar components (two brake sensors, throttle, and display), with a lump covering the junction where the four smaller cables emerge. Securing the lump to the head tube seemed like a good way to keep the motion in the (presumably) more flexible smaller cables:
From the rear:
I later bound the four connectors into a cluster using cable ties to further reduce the clutter and keep them from tapping the top tube.
The clip captures the cable tie in those indents:
The overhangs require easy cleanup with a square file to get rid of a few droopy threads. Avoid the temptation to print it standing up as an arch, because you want the perimeter threads to go around the whole thing, not across the thinnest sections. Trust me on this.
The OpenSCAD source code:
module HeadClip() {
CableOD = Harness[OD];
difference() {
linear_extrude(height=HeadTube[LENGTH],convexity=10)
difference() {
hull() {
circle(d=HeadTube[ID] + 2*WallThick,$fn=FrameSides);
translate([0,-(HeadTube[ID] + CableOD)/2])
rotate(180/(FrameSides/2))
circle(d=CableOD + 2*WallThick,$fn=FrameSides/2);
}
circle(d=HeadTube[ID] + HoleWindage,$fn=FrameSides);
translate([0,-(HeadTube[ID] + CableOD)/2])
rotate(180/(FrameSides/2))
circle(d=CableOD + HoleWindage,$fn=FrameSides/2);
translate([0,-HeadTube[ID]/2])
square(0.75*CableOD,center=true);
translate([0,HeadTube[ID]])
square(2*HeadTube[ID],center=true);
}
translate([0,-(HeadTube[ID]/2 + CableOD + WallThick - CableTie.z/2),HeadTube[LENGTH]/2])
cube([HeadTube[ID],CableTie.z,CableTie.y],center=true);
for (i=[-1,1])
translate([i*(HeadTube[ID]/2 + WallThick - CableTie.z/2),0,HeadTube[LENGTH]/2])
cube([CableTie.z,HeadTube[ID],CableTie.y],center=true);
}
}
I briefly thought of holding two pieces together around the head tube with M3 screws, but came to my senses: a cable tie is exactly what you want when holding a cable in place. Right?
The Smell of Molten Projects in the Morning 
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