Hello everyone,
Not sure if this should go into the mechanical forum but since it is a Brompton I thought I would post here.

I am having a problem with my Sturmey SRF3 on my C type Brompton. I am
able to shift fine into all of the gears and coast fine in gears 1 and
2, but in gear 3, there is a fair amount of drag on the pedals and if
I back pedal at all in gear 3 the hub makes a lot of bad sounds. I
consider myself pretty familiar with the older Sturmey AW hubs so I
decided to take a look and see what I could find. I checked the right
cup and it was adjusted correctly, about half a turn out from finger
tight. I took the hub apart and checked for anything that was worn or
chipped and did not find anything that looked out of place. Please
let me know if you have any ideas regarding this. Oh and it isn't the
cold temperatures which was the first thing I thought so I brought it
inside and let it warm up over night and have the same problem inside
on my work stand.

Thanks,

Chad