Hello all. Sorry for the delay I have been away.
It is a 3 speed and the hub is from a Rayleigh Chiltern circa 1990. Sorry I am not sure the exact name of the hub. I have attached the photo.
This is an old photo and everything is a lot cleaner now.
I adjust it just like 79pmooney explained and it has been fine for many years and now it just won't stay in 1st for more than 10 seconds.
I have tried spraying some lube into the gear shifter and it's no better.