The Reaction represents something significant: it's CUBE's own Formula 1 class of mountain bikes. It's light, stiff, responsive and built for one purpose only: to go as fast as possible off-road. To that end, we gave it a complete makeover for 2018. Featuring fast-rolling 29 inch wheels, our new Reaction frame makes use of our C:62 carbon and is even lighter, even stiffer and even more responsive than the one it replaces. No, we didn't think that was possible, either, but try telling that to our perfectionist design team. With a smooth air sprung fork, wheels built in-house here at CUBE and a slick, reliable Shimano SLX and XT 2x11 transmission, there's only one component missing from the Reaction: you.