Some recent changes to my side of the Brompton fleet so here’s the status…
All are now running “minimal rain-guards” (yes, Sydney has been rather wet – for far too long).
Chpt3 S9R-X with 38T chainring & 13/15/18T cogs (GIs 76-22)
After lowering Rudolph’s 6speed cog setup to the lowest feasible (15/18T, GIs 66-22), installing a 3speed shift conversion has given/restored some upper range flexibility (you never know when a tailwind will come along).
S4R-X with 46T chainring & 11/13/16/20T cogs (GIs 69-38)
S6L-X with 42T chainring & 11/13/16/19/22/25T cogs (GIs 62-27)
Even though BB’s 4speed setup was running well, I decided to make use of the 7speed freehub for some differentiation to Clarence. Tried a SunCord tensioner but disastrous, waste of time (wrecked the pusher due to excessive drag/friction in jockey wheel movement, maxxed the dogleg (start to contact with frame) as 5speed-capable only).
Obtained the new Thx4Ride derailleur & shifter & it’s running really well – although the Thx4Ride shifter steps didn’t mate with the 7speed cassette setup, so I’ve resorted to a 6speed cassette (I had to use mostly 9speed spacers, with thicker spacing for the first & last cogs – & a thin spacer to fill up the freehub).
The shifter benefits are that it’s very light (52g), mounts behind the bar (no fold clearance issues) & has a light action – all superior to the SunRace shifter in use with the 4speed setup. It would be nice if it is a trigger shifter but as a thumb shifter I’ve positioned it on the bar for thumb down-shifts & index finger (under the bar grip) up-shifts.
BB’s operation is delightful. Rudolph may have my lowest gearing option but the lightness of BB seems to put the two on a par?
Next tweaks? Maybe/probably finished?