Homebrew EFI -- the plumbing

GPz Parts

Grabbing the whole GPz1100 kit and kaboodle means that I've got the whole pile of motorcycle-friendly parts. In particular, the fuel pump and fuel regulator are external units rather than built into the tank.

System / Fuel Pump / Fuel Reg:

Low Pressure Fuel

There's a stock outlet stub from the tap, is that going to be big enough?
It'll need a fuel return stub back into the tank, and some way to stop that draining / siphoning.
Alternately, a small header tank with cooling fins could fill this role instead, topped up from the real tank.
I'd like to provide some way to access a tail tank while on the move. If the EFI pump is pulling from the tail tank and returning to the main tank, that should take care of moving the weight forward. This might involve some taps and non-return valves. 10L would be plenty.

High Pressure Fuel

While most vehicle fuel systems use solid fuel rails, etc, this isn't really convenient for a V-twin. The injectors are solidly held into the throttle bodies already, thankfully. All the fuel plumbing is going to have to use high-pressure EFI fuel line and clamps, but what the hell, there's only two injectors. Hopefully I can get all the bits in the right sizes (the pump outlet is particularly large). If the bit of line connecting the jets could be bigger than the injector stubs, that'd be good too, just like the stock GPz fuel rail.

Manifold Air Pressure

The fuel pressure regulator uses MAP as a reference pressure. The ECU may need a pressure input too. There's a vacuum reference stub on the top of each throttle body, these can be connected with vacuum hose and T-pieces. An inline fuel filter could be used to provide some extra volume for damping out pressure fluctuations.

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