Box Three Prime 9 conversions

derailleur hanger extension (for Box Three 11-50T) :



Microshift Acolyte with 12-42T comparison (no extender required):

acolyte rear mech.jpg


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  • 1x8 tuff little unit.jpg
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Box three 1x9 now fully working: observations - chain needs to be super tight to swing that big mech arm down, shifter cable tension also needs to be very tight - the action is definitely nowhere near as light as Microshift.

Overall this kit is more work than Microshift and not 'plug+play' on a vintage bike - requires a little ingenuity

looks the part though:
It's a long way down, isn't it? How much ground clearance do you have when the arm is fully extended?
Not a lot, probably not great for plummeting down a rocky escarpment. On balance I think maybe the 11-46T variant of this kit is more practical perhaps in combination with a 36T or smaller chainring. Big balloon shape tyres help raise things a bit. The 50T dinner plate sprocket looks pretty mean though so I am happy withe the result.