Really?
I'm not convinced of the science behind this.
Is this brought about by the horror clips of gasoline explosions at gas pumps ignited by static discharge? In those cases the static charge is generated by the operator getting into and back out of the vehicle. Most commonly the static charge is generated by the synthetic clothing against the synthetic seat covers. Ground straps on these vehicles have no effect.
Fuelling a race bike is different; very little in the way of synthetics, the rider getting off the bike is probably not fuelling the bike, the time of year when these events take place it's very hard to generate a static charge (humidity). Where there is potential to generate a static charge is the fuel moving through a plastic fuelling rig. I'd feel safer if the fuelling rig & operator were grounded or better yet a grounded conductive fuelling rig (no plastic).
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