Do you lose all electrics when it cuts out?
If so it sounds like the problem is perhaps the positive battery terminal itself, either the terminal or the wire to it.
If not.... I'm Currently doing the wiring loom on the cinq so i'll assume it's a similar setup power/ignition wise. If so there's also an ignition trigger wire connected to a bullet type terminal, which "should" be connected to a fuse (Maxi?), so it could be traced back from that to the connector to check that's secure, the fuse too, check that's not wiggling about.