There's left luggage at HR but I'm not sure how expensive that is.
There are multiple self storage units in and around London too but I'm not sure how they work since the fertilizer bomb plot.
directory services (yellow pages and thomson local)
http://www.yell.com/ucs/HomePageAction.do
http://www.thomsonlocal.com/
The major cycling groups in London who might help are
cyclists' touring club -
http://www.ctc.org.uk/
London cycling campaign -
http://www.lcc.org.uk/
Try calling/e-mailing around the bike shops in London and quiz them
These are some of the reputable shops
http://www.condorcycles.com/store.html - quite possibly the best in London
http://www.brixtoncycles.co.uk/find_us.html
http://www.bikefix.co.uk/index.php?u...&bsm_code=#a61
http://www.onyourbike.net/
http://www.sigmasport.co.uk/app/web/...&qssubmenuid=0
The bigger chains that may also help but I strongly recommend you avoid Evans Cycles.