Since it only seems to happen when you hit a bump, check those items that might come loose and shut down your engine. Coils and wires already mentioned. Loose, weak or missing sidestand spring. Sidestand switch and wires. Ignition switch wires. Kill switch wiring. Headlight bucket wiring.
I doubt you have a CDI failing. The plug might be loose on it though. Inspect all your wiring if you can't find something simple. Usually, something is loose and making/breaking contact to give you that condition.
