Over past 2 wks, i have replaced drive chain, sprocket, rear drum, cush rubbers on my 74 850. 20T replaced with a 21T sprocket. New Fedoro brake shoes. Previous was shark toothed as was drum sprocket and chain showing lots of slop...Id put 22k miles on these since getting the bike with 7500 showing on the clock...now its just under 30k. Unknown if those bits were all original.
New extra tooth sprocket is really noticeable...i can easily take it to 45-50 mph in 2nd at around 4k rpm. Previous, id cruise at 4k, 55-ish in 4th....now im down shifting to 3rd at 55.
For the first time in my stewardship, the rear brake is now actually very good...previous, it was always vague, pedal needing lots of travel from start of friction point to point of applying real stopping force...could not adjust that out as drum would scuff well before pedal travel reduced...so put it down to out of shape drum...shoe renewal did not help...now a new drum and fedoros seem excellent..pedal just needs light tap and bike is slowing dramatically.