Well, I've been informed of the end result regarding the clutch issue by BMW.
BMW UK stand fully behind the technical work that SPC have done. A top-notch job even (that might be my words, but its the general impression I was left with after talking to the guy from BMW UK).
SPC didn't fit the existing clutch, and they never saw the bike before the current one wore out. BMW Battersea (or BMW UK, depending on how you look at it) did fit the existing 2nd clutch at around the 25k mark due to a failed oil seal.
BMW have stated very clearly to me that the worn out clutch (16500 miles or so before wearing out) has nothing at all to do with the engine failure that occured 40 odd miles after the bike had its 3rd clutch installed.
Thats the good news.
The bad news...
I am still left with the impression that Pete did not contact BMW on my behalf due to my 'unhappy camper' feelings about having to pay out 850 odd quid for a clutch that shouldn't have worn out that quickly. It is possible he was indeed waiting for a standard visit from BMW that was supposed to occur during the time my bike was having its clutch replaced, but as it turned out I got the bike back before that visit happend (I think the visit was delayed for some reason or other). In the end, this side of the equation may just be down to timing and Pete may have indeed going to be talking to BMW about it - the engine blowing up escalated things slightly so its possible I got to talk to BMW sooner rather than later as a result.
The promises to ring back which never happened on a timely manner are probably the biggest issue I had with SPC - I was writing off the TomTom rider power cabling down to experience of leaving something in writing rather than just talking about it whilst there. Since the engine failure (and the coincidental post 12 or so hours beforehand about the clutch on these forums), Pete has been very communicative and indeed has been calling me exactly when promised. This is all very good, and its going a long way towards me being a slightly happier camper.
SPC, very rightly, charged for the clutch replacement. I have no quibbles with this, as they never saw the bike before it came in with the issue.
BMW on the other hand have now stated very clearly that they will not be refunding even part of the clutch cost. Their perspective is roughly that its the first clutch that I have paid for in 42,000 miles (the 2nd clutch being done under warranty). No full investigation into why the clutch wore out after only 16,500 miles is deemed necessary by BMW, and this appears to be mainly due to the entire engine being replaced, and SPC taking extra care with fitting the new engine and putting the clutch back on it.
Whilst I appreciate that BMW are meeting my expectations by replacing the engine for the equivalent of 'free' (I have to pay a token amount to make the warranty legal - again something I'm happy to do as a new engine without a warranty wouldn't be a selling point on the bike in my opinion), I don't really appreciate this 'totally not related to the engine failure' issue being bypassed. Something was wrong for the clutch to wear out in only 16,500 miles - my riding style has not changed that significantly over the last 2.5 years since I got this bike. This is self evident in the fact that my tyres have all lasted more than 6,000 miles (I replace them if they won't last another 6,000).
I'm not a boy racer
Anyway, thought you might want an update - I'm happier now with SPC. It seems I just got off on the wrong foot somehow and we are now back on track in that regard.
This isn't a 'SPC are great' type post - they are now meeting expectations after what started out as bad customer service and then escalated into an increadably bad experience due to the engine failure - which from what BMW are telling me has nothing to do with SPC's technical work at all.
Feel free to ask questions if you want anything clarified. I'm trying to be as fair as possible and to state the truth as much as I can without getting clouded too much by my own viewpoint.