Phil its the rubber hose from the fluid pot to the mastercylinder thats required. Lot of motor factors DON'T stock this they usually palm you off with fuel hose, which then sweats. I got mine from DTR off his race support van in the paddock, A&R racing also stock it
I still might be able to help anyway - the standard SS hose to the res is about 12cm, and I have a spare 916 rear master cyl with a 23cm length on it ... sounds about double to me
thanks for the replies guys. Most motor factors near me will not stock it as skid mentions. I'm off down to pro-twins tommorow on a ride, so they may have something. Phil , you have PM, thanks, you're first on my list mate.