Without the red key you're a bit screwed I'm afraid. The one remaining key cannot be re-registered with a new code without it, or for that matter any replacement blanks you get cut.

You can obviously use the bike with the one key you've got, but the stolen keys will remain registered to your ECU and your bike is at risk of being stolen (assuming they can make the connection between the keys and the bike).

The only proper way round it is to replace the ECU, ignition switch, seat lock, petrol cap and get three new keys including a red coding key. If you get lucky you might drop onto a full set of the above used, but they won't be particularly easy to find. The other alternative is to do away with the immobiliser altogether by sending your ECU off to somewhere like Off The Road in Germany who can reprogramme it and disable the immobiliser. This will be the cheaper, easier and quicker option.

For now, keep your bike in a locked garage and get yourself some serious padlocks and chains. The other problem you've got is, should the bike (god forbid) get nicked, insurance companies won't pay a penny out if the key(s) have been stolen.

Sorry to be the bearer of bad news. I feel for you.

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