RSV1000r (2004) not starting, just turning over.

Hi, I have a 2004 rsv1000r. Its been fine until last month when it wouldn't start it just turned over. I took the key out for 30 seconds put it back in then it fired up. Again this happened where it just turned over but this time took key out put it back in but nothing. Had to do it again and again whilst stuck in a petrol station yesterday and took 10 to 15 mins of trying to get it going before it eventually fired up. What I think it may be is that the bike is not picking up the key?? When it fires up eventually it fires up straight away, it doesn't struggle at all, which is making me believe its electrical. Also a couple of times when I have gone to switch the bike off it has stayed running even with the key out! then after 10 seconds or so it turns off by itself! Whilst it was running without the keys in the clocks and lights were off just as if the bike was turned off. I rang my local apprilia dealer and explained all this and they said they could look at it but didn't know how long it would take them to find the problem, at £40 an hour I didn't want to risk it. The fuel pump also sounds at though its kicking in still when the bike is parked up switched off. So any help/ info will be helpful. There was another post with a similar problem I found (dated back to 2011) but no conclusion.
Please Help :confused

Are there any wires that are prone to corroding which can lead to starting issues??

Cheers, gave him a ring and explained but he couldn't really tell me anything without having a look at it, and he is about 3 hours away from me unfortunately.

Thanks Andreas, yes it's had a good few squirts of WD40 down the barrel in its life so will definitely give it a clean out with brake cleaner. And no it doesn't have an alarm fitted.

Redratbike, yea that sound just like mine! I had a tinker on with it last night and took the ecu off to have a look for any corrosion but the back doesn't seem to budge. May take it somewhere for someone to take a look inside. Thanks mate.

tried the brake cleaner down the ignition barrel and looking at the pool of black liquid on the garage floor it had obviously got some crap out! But unfortunately no luck.
What is strange though is the bike is left on an optimate all the time, I disconnect it every time before starting. Anyway, it wont start until the battery is just about flat on what seems like the last bit of power left in it. Done it a few times now. Iv ran the battery down so far today it was just clicking and not turning over, left it ten seconds tried again and it managed to turn over once (just) and it fires up! Baffled isn't the word:banghead

Had bike into aprilia dealer in Thirsk, North Yorkshire. He said the problem was the ECU so I bought a second hand one mad dropped it off . He phoned me the next day after fitting it and said it was not the ecu, it is he immobiliser unit and it needs a new one. It is quite expensive and I don't want to spend any more money on it especially after buying a second ecu.
I know people know how to bypass the immobiliser but keep it hush hush as not to let the info get into the wrong hands.
Can anyone PM me on how you can do this. Bike had been off the road a year now and really want to get back on it! Any help much appreciated!