One more comment. My riding buddy yrs ago bought for almost no money a perfect Tri Sprint RS. Three dealers could not get it to run right so they got rid of it.
The problem? The fuses in the fuse panel had worked themselves upward, causing various intermittent electrical issues. But you could not really see this by looking at the fuse panel. The fix? He pushed all the fuses back in and the bike has run perfectly ever since.
Don't overlook the obvious.
Thats actually a very interesting point and reminded me of another little issue that completely slipped my mind. Once I came off the motorway down to lower speeds (30-40mph) the bike 'glitched' for a split second and the speedo stopped recording speed. The bike continued to run, and the tacho continued to work but the speedo read '0 mph'.
It continued like this for about 5 minutes, only when I opened the throttle and got up to higher speeds it jumped back to life again and started working as normal.