Thank you chas58 for posting your hands on knowledge. I'll go try to figure out the calculator this evening...

I've kind of mixed two builds into one here, because I was thinking of testing out the MY1018 on the Soma before moving it over to the my FS MTB, but it turns out I'd have to invest in many parts that aren't compatible, so I'm switching gears once again (pun intended!). I'll have to start another thread for the MY1018 FS MTB hill climb assist only build.

Back to the actual Soma B-Side V.2 Belt Drive build powered by a BBS02 750W 48V mid-drive:

My Gates Center Track Carbon Drive 50T front sprocket arrived and from what I can tell the outer flared lip is about even with a 42T Lekkie Bling Ring, so I think it will clear the BBS02 gear reduction hump without modifcation. The two chainrings are about the exact same size in diameter.



I won't know for sure until I actually test it on a BBS02 and play with the inward spacing off a 130BCD adapter spider. My fingers are crossed that the CS-RK3 cassette in back will allow enough outward spacing for the rear 28T CDX cog to line up. I decided to stick with the Soma single speed recommended 46T X 26T ratio of 1.77:1; 50T X 28T comes in at 1.78:1. That setup calculates out to a 118T Gates Carbon Drive belt at 432.79 chain stay length.