[size=2px] but think there is a replacement bit of pipe to replace the section and remove the flap[/size]
I've heard of this but I'm a bit dubious. Clearly BMW didn't put a flap and servo motor in for no good reason. I believe that the operation of the flap has an effect on low to mid range engine revs. so I'm reluctant to ditch it. The solution so far is good old ebay - 2nd hand flap and servo for £89 inc. p+p and I hope that the seller is as good as his word that its in full working order. I think the £1300 figure relates to later models ('14 on?) because the flap is incorporated in the exhaust and not a separate part. I've checked several non-franchised BMW parts suppliers for a new pattern part but its not listed. I've not checked Motorrad UK for a genuine one but I suspect it will be in the £500 area.
Wish me luck and I'll keep you posted.
Forgot to say, when I got the old flap mechanism off it was completely seized and lots of lubing has freed it up a bit but not enough to get it to operate via the servo which works when not attached to the flap, hence replacement part.
[size=0px]I would give your local dealer a ring. Don't think they are as expensive as you think.[/size]
You're right RTman, not £500 but still coming in at £215+VAT, so I'll stick with my ebay option. According to BMW Belfast, who I just spoke to, he's only sold 1 in the past 12 months but the workshop has worked on freeing up several. Mine is beyond help alas.