I would caution you about trusting zipties in a small diameter application like that, especially where a fuel spill could be a danger. If you wrap a ziptie around something and it uses 40 teeth on the ziptie, the final tightening can be pretty much exactly what you want. When you wrap around something that only uses 10 teeth, the difference from 1 tooth tighter or looser is fully a 10% change in tension.
Pull too hard, it strips the plastic ziptie. Not enough and vibration can walk it right off. Had a fuel line of my own slip off the OEM fuel tank fitting, and was fortunate the engine wasn't hot or running, have seen a fuel fire before.
Now it and every fuel line and pulse line and vent line on that engine has a 1/4" - 5/16" radiator clamp (ring clamp, worm screw clamp, hexhead adjuster toothed clamp, call it however you know It) on it screwed down tight at both ends. Looks industrial, solid, and safe, which it is.
NOTE: I resisted the urge to buy a handful of 1'4" - 1/2" clamps they had right there on the shelf at Home Depot, and instead waited for 2 boxes of 10 clamps of the smaller range to come in from ebay. Had tried the larger range, left a huge ugly tail hanging out, getting in the way in tight spaces.
FYI: My fuel lines are run as fuel tank, shutoff valve, filter, fuel pump, another filter, reducer insert, carburetor. Vent lines from valve cover and fuel tank go to a tee (w/ reducer insert in valve cover vent line), then to an outlet filter. Pulse line from valve cover (correct placement after the flutter valve) to fuel pump. That's 22 clamps. No fear.
