I've been riding road for almost a year now. I do 100-150 miles per week. I love doing 100+ mile rides on the weekends when I can.

I want to get stronger and better on climbs (like everybody) and have been using an indoor trainer frequently with Zwift on my road bike, but the tire is getting really screwed up. I don't have a spare wheel, and don't want to change my tires all the time, but I do have a spare MTB with smooth street tires on it.

What impacts if any would training on a MTB bike (position) on a trainer have on my road riding? I hate to loose any of my saddle "callus." Yeah I know find a spare wheel . . .

-And bummer, Zwift does not let you change the wheel/tire size yet.