Trolling motors more efficiently "pull" a boat than "push" one. That being said, a 112lb TM is a 36V TM, 3 batteries. Have you planned for that much weight and if they'll be forward, like inside the casting deck, remember you could also be in the front fishing - lots of weight forward. If planned out, it's not a bad thing but unplanned it can throw your center of gravity (COG) off. The '72 shaft was the longest they made until fairly recently but now they have more lengths, depending on the model of TM, up to 100". I think these newer lengths came about because bigger boats wanted a trolling motor too and the bow was higher in the air. For your 222 I think that the 72" should be fine. I see they also offer a 62" on their hand controlled models, which would be great for a 170/175. I'm using a RTA-17 removable mounting backet.
