really big tire 'cross bike

Really big tires require really long seatstays....longer than I can buy. I did some 'boots' on these that gave me the additional 1/2" so the 49.5 mm wide tire would fit. This bike is a 'cross bike but it's a gnat's whisker away from being a 29er.

Here's the fork......not a mountain bike fork, a big-tire 'cross fork. It's stouter and wider than a stock 'cross fork but it's not as rigid as a mountain bike fork.
The wishbone stays are a little less likely to flex under hard braking as they have a thicker wall and larger diameter. The shock absorbtion will come from the tires, not the frame in this case.

More NOS rifled prestige tubing...seems to be my choice as of late. The quality of Tange is really the best.