Originally Posted by Lady82

thank you for your response. I am at a loss myself. Pathfinders in the same size, with the same tube, same PSI, on the same rim are larger.
Different question. Would it be insane to try to use those WTBs on my husband's fitness bike with the rims that have an inner width of 15 mm?
My previous bike had wheels with inner rims of 21 mm and tires that were 29X2.4. The ratio is about the same...
The width between the chainstays on the bottom is ok.