Rebuilding a leaking vacuum actuated motorcycle fuel petcock. 1978 Suzuki GS 750

This is an uncut video of me rebuilding a vacuum actuated fuel petcock from a 1978 Suzuki GS 750.
It’s got a few miles in a few years on it but it’s back to good as new.

This petcock is one of those oddballs that don’t have an off position.
It has prime, on and reserve positions.
If the float bowls are dry you have to set it to prime in order to get the bike started.
Once the bike has started you can move it to the on position.

The on position will not flow any fuel unless the engine is already running.
The reserve position is fairly self-explanatory and is used once you run out of fuel in the on position. It should be used only get you to the nearest gas station.

This is one of many parts of my café racer build.