~ 2012 fx 7.3 bottom bracket size?
03-08-18 | 07:36 PM
#2
Senior Member
Joined: Feb 2017
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From: Northern Shenandoah Valley
Bikes: More bikes than riders
Welcome. It's very likely one of those. My 2015 Trek Verve has a 68mm bottom bracket bearing, and I imagine a 2012 FX will be similar. The only other likely option would be 73mm, which is apparently within the range of your motor. It's easy enough to measure, though. Just measure the actual width of the aluminum frame shell around the bearing. 68mm is about 2.7" and 73mm is about 2.9".
03-09-18 | 12:03 PM
#3
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From: Connecticut
Bikes: 2000 Trek 720 Multitrack (plus)
Standard English threaded bottom bracket either 68mm (road) or 73nn (mtb) wide. The threading for both is the same; the width of the shell/frame is different.
