gas shutoff

[tekebird]

how is this accomplished on modern sportbikes?

[55chevr]

The handlebar switch shuts off fuel pump on fuel injected bikes.

[tekebird]

What about a vacuume operated petcock.  basically serving the same safety wise as the elec fuel pump.  If the engine is not running producing  vacuume no fuel flows.

Hit the kill switch engine stops.....vacuume stops, fuel flow stops.

How about a mechanical Fuel pump

[Seldom Seen Slim]

I'd prefer something more guaranteed.  If, for instance, your hot engine hot hot engine is so hot it's begun diesleing -- you can shut off the ignition and it'l run on and so will the vacuum supply and ergo the vacuum-operated fuel pump.  Ditto a mechanical pump.

If you're running nitromethane we want you to have a thumb/finger-operated shutoff on the handlebars, no variance allowed.  If you're running nitrous oxide or race gas and have electric solenoids or fuel pumps -- the factory (or your own) electrical lkill switch on the handlebars is enough.

If you're running gravity feed, as long as you can reach the petcock shutoff with either hand -- while you're riding -- that'll pass tech.

If you're running nitromethane AND gravity-feed for the fuel -- you're a braver man than I, McGee!

[Frenchinjection]

Sorry to wake an old post but it has some detail that is useful.  One being nitro and a definite mechanical fuel shutoff.  But what about EFI and Methanol with a mechanical pump.  Kill the power and the injectors stop.  Even if the engine is dieseling without fuel it will stop.