I had the MkI's on my Commando re-sleeved with stainless way back when I rebuilt the bike.. in short I have NOT been happy with the result.
In fact I am in the throes of over coming yet more dramas with these same carbs.
What I am doing is ~ putting together several 'original' MK1's to kep me rolling, till I have sent off several 3.5 slides to a Teflon coating company here in Australia.
They are are going to 'give it a bash' in regard to teflon'ing the slide/s only and I will have a tinker with these.
(The manager being a Model 50 owner is keen to follow this exercise thru as well . This of course as I have suggested to him is a 'vested interest' in this exercise, as I have a few more than lightly interested bikers here in Australia watching and waiting to see the results are._)
In short this is going to be a process, and time will tell ~
I will get back with my results. 8)