Hi ED just spotted this post,
The 50 miler was a great annual event for us, and was always the race to win, 26 gruelling laps of snetterton, what can only be discribed as "shear hell - physically".
usually i got of and could not feel my hands or feet for at least an hour after, I was a mear youngster, what it was like for the older guy's I have no idea, but I never had an issue changing gear or clutching, but as soon as it was over it was hell.
always held at snetterton, one of the great super fast circuits of that erra, but its even better now they have made the new mods, been there on the bant.
regards Derek