Another reach-out to the collective mind here;
My 79 T3 850 is cosseted in a nice dry garage, only ridden in nice weather, not ridden hard either, in deference to its age. I took it recently on a fairly sedate mooch though the countryside with a slow plod back through town on the way home after a tea stop at a mate’s house. Probably did 30 miles max. On the way home the clutch lever needed to come back further and further towards the bars to enable gear changes and in traffic at the tail end of the ride, I found it very hard to get neutral; could just about achieve it if the bike was still rolling, but stationary it wouldn’t find neutral.
When I got home I had to turn the bike off to select neutral. Next time I rode it, it was back to normal but that ride was probably only 5 miles or so.
Any thoughts and advice gratefully received.
Was it a particularly hot day?
My 1000s clutch seems as though it doesn’t lift enough in stop start traffic when its a mad hot day, normal service is resumed when the traffic gets moving and it cools down, I think that its just expansion of the engine due to the excessive heat👍
Not an excessively hot day; funnily enough I’ve just taken it out for another quick spin and had the same thing happen. Start her up, let it warm up a bit then ride up a dual carriageway with a 50mph limit, stopped at about two sets of traffic lights in about a three mile stretch.
Then rode through light suburban traffic for about 5 miles, and just started to get the effect. Rode back pretty much the same way, and by the time I got about half way back I was having to put it in neutral while still rolling because once stopped it flatly refused to find neutral. Carried on for another little nimble along the seafront and back home. I should think I did no more than 15, 20 miles tops and none of it riding hard. The last few sets of lights I stopped at I really had to squeeze the clutch lever back to the bars otherwise there was a very slight amount of creep. Got home and tuned it off and it went straight into neutral!
Long shot check the condition of your clutch cable 
Actually, that’s a good shout just to replace it anyway. No idea how old it is, and maybe a cheap cure! Thanks for the idea, I should probably have thought of that, but the pessimist in me was concentrating on much worse possibilities!
I think I’d try giving the clutch adjustment on the back of the gearbox another quarter of a turn out as a first thing to ensure I definitely had enough free play in the clutch lifter once the engine warmed up, then you use the bottom & top adjusters on the cable to remove any excessive slack in the lever 