The BB on my Suburban took a standard Ashtabula crank without issues.
Just replace the crank and the rear cluster and you can go to a non-FFS
If you have Positron, you can keep it or change it... the two technologies are not essential to coexist, they just usually do. If you change the positron ferailleur, you will also need to change the shifter.
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Slow Ride Cyclists of NEPA
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