Zapped by a sputnik? The earnest search for clues

My mysterious altercation with the tarseal of a familiar cycle lane near London's moody Hogsmill River posed such worrying problems and question marks that I felt only a return to the admired St George's Hospital in Tooting, London, on Sunday would turn up the answers.
Last Monday I had been cycling home with a backpack of groceries from Aldi's supermarket in neighbouring Epsom when the ride was interrupted sufficiently to gather a modest crowd round me and the bike. Only feet beyond the spectators waited a pair of ambulances.

Sputnicked? ... The bike is released from the hospital's vigilant security watch, bearing a note, but sadly no clues about how it was struck down, rider and all.

You've probably noted a gap in the story, between the backgrounding and this totally changed scene. One moment, I'm cycling and the next – almost – I am on the ground, bathed in blood, and surrounded by strangers.

A Salisbury connection

As a reader, you're certainly entitled to know what happened.
As the somewhat reluctant main character in the drama, I feel similarly. And as I am in the role of chief character, surely discovering what happened ought to be simple.
Did a maddened bull race out from a hedge and gore the bike? Perhaps a UFO with steering problems landed in exactly the wrong place, sprawling me onto the track. Or following recent political turns, might it be that my birth in Salisbury is the connection? Might a cause be that of all the countries in the world I sailed to, I didn't ever get to grace a Putinland jetty nor anchorage.
At this stage I have to say that your narrator, the principal character who ought to be able to tell all, has very little idea about how it happened … and in spite of an investigative visit to good old St George's.

Blood, yes, clues, no

I walked all the way to the hospital yesterday to inspect and collect my bike, the method of travel that should provide the clues. I expected the damage to show itself, where a car might have struck me, or perhaps an aggressive overtaking cyclist had kicked in the spokes, maybe a guided sputnik hit home.
Would you believe it? Plenty of six-day-old blood on the machine, but otherwise not a hint of the cause of the crash.
There's been no chance of anyone tampering with the evidence because the machine has been in the conscientious care of the hospital's security experts, Terry Wynn and Ben Miller. Perhaps a Twittering is the way to go, to see if witnesses can be found …. (Watch this space – hopefully…)
Thanks very much for visiting the blogs for my adventure book, Sailing to Purgatory.