Thanks MM,
that's good to know. I did start leaning out the mixture (LSN first - prob about 1.5 to 2 turns from default) but I think I might richen it back up a bit until I've done about 10 tanks.
Don't want to fall into the trap of trying to get too much out of it too early

It was really pulling nicely though on the last tank I ran - can't wait for it to really start running properly.

Thanks again for all the useful info - been a big help to this noobie

cheers