My friends say that buying a bike like the Santa Cruz Tallboy is the most value for the money because it’s technically buying two bikes for one price. Help me understand how one could switch between a 27.5+ to a 29er on the fly. What parts are needed to make the swap?
Well, technically that is true though there is a bit more to it than that. The most realistic way to derive at a bike where you can make the tie/ wheel swap in a reasonable amount of time (say 15 minutes) is to have a spare set of wheels wrapped in tires with cassette, brake rotors and a fork.
You could theoretically get by with just the fork, wheels and tires but keep in mind you’d be swapping the cassette and brake rotors every time you wished to transition from one size to the other. It could easily become a half day’s project.
The reason bikes like the Tallboy are able to make the transition at all comes thanks to adjustable frame geometry. Santa Cruz makes use of a flip chip- literally a piece that can be flipped and run in one of two directions at the upper rear link. This is responsible for the rear end; the fork swap covers the front. All told the difference between the 27.5” and 29” wheel is barley visible to the naked eye but requires compensation at both ends of the bike to successfully transition from one to the other.