Probably completely off here but I would keep the sirrus as a work horse and buy a road bike for a bit of extra speed eg btwin triban 3
agred, upgrading the bike is pointless. A bit like buying a basic Ford Focus and paying to have electric windows and aircon installed.
Parts are much pricier as add ons than as a complete package with a bike
Most wall racks will take 2 bikes just put them head to toe (I could use a number here but don't want to offend).Thanks for the replies/advice
The idea of two different bikes vs one slightly better one is appealing. i got it in my head i've only room for one, this is why i got fixed on the upgrade or sell route.
The advice about buying another bike with the money made me think about my storage methods.
At the moment the bike is stored on a wall mounted rack held by the frame. I could change this to simple wall mounted hooks and store the bike upright on the front wheel making space for two bikes with roughly the same footprint.
Looks like i will keep the Sirrus as it is. Continue saving the unspent petrol money and start looking for another bike.
Thanks Guys.