This is the kind of detail I have been searching for on these forums. Wanting to find out why everyone is content to stay on the default 20" wheels rather than increase the radius of the wheel. I would suppose that this should make for a more 'powerful' bike that could move on the flats and still be agressive [given good bent muscles] on the climbs.
I guess that I would assume that would require the SRAM 81 gears.
How much did these mod's cost you? How long had you used the Catrike as delivered before the modifications? Any turning instability?