انا للہِ و انا الیہ راجعون
Sad to hear about your loss.
Register an FIR just to be on a safe side. BUT, as for a harsh truth, you wont find your bike now. Forget it.
We can only HOPE for the best. And only HE (ALLAH) knows whats best.
Give Sadqa, Register an FIR, and if you have some contacts in Police, you MAY get an increased chance to recover your bike.