Righto, applying Grumpy's 'spin to win' test, it is definitely contacting the bed knife. I'll get some close up shots tomorrow and post them. One other thing it was doing in my quick experimental mow(tm) was the ignition seemed to randomly cut out then it would either die or pull itself together again. Let's save that for once we've got the reel/bed knife issue resolved (as it may be (as you say Darryl) just the strain on the drive train caused by reel/bed knife)...

Cheers Guys (and thanks!)

Jeff