My currently installed setup is;
Bafang BBS02 500W, 42T Lekkie, SRAM DualDrive 8 spd cassette (11 - 30), 20" wheels.
After much comparing of reports from the Sheldon Brown Gear Indicator, I note that my DD exhibits better developments in both low and high range gears than does the Alfine 8. The charts also reinforced how many 'double-ups' there are with my (too many since adding the BBS02) 24 gears.
One of the Bafang Higo e-brake connectors is fitted to a Wuxing 'Big Green Button' which I use as an electric clutch.
There is a front derailleur mast on the asymmetrical aluminium BB for the BBS02 and although the Precialps multi chainring adapter has been mentioned, what I consider stumbling blocks for multiple chainrings are;
- Lekkie 42T chainring is a 'wide / narrow'
- Larger chainrings not recommended for the BBS02 (Mk i controller FETs)
- Keeping the motor revs up while in a larger chainring
- Retaining my chain line
- Would the BBS02 Mk1 500W compensate for an adequate gearing using just the 3 hub gears of the DD3 (thereby allowing a stable chain line for an enclosed chain guard)?
- Any ideas on a final drive cog size for DD3 hub / Alfine 8?
Or, a small 2 speed overdrive unit sited between BBS and rear wheel.