The other details are relatively conventional, but seem well thought out. The Supernought features a threaded 83 mm bottom bracket shell with the lower portion of an ISCG chainguide mount and a built-in guide over the 18-tooth steel idler pulley taking care of things up there. The rear brake gets a 200 mm mount and external routing (the derailleur cable is routed internally), and bolt-on dropouts provide options for running either a 27.5’’ or 29’’ rear wheel, as well as +/- 10 mm of chainstay length adjustability (more on that in a minute).
There are ample rubber guards on the chainstay, seatstay, and downtube, along with built-in fork bumpers behind the straight 49 mm headtube. The rear dropouts, interestingly, use 148 mm Boost spacing instead of the more common 157 mm DH standard, though we’ve seen a number of other recent DH bikes (including Neko Mulally’s recently announced Frameworks one) go that route as well. The Supernought is offered in four sizes, labeled S1 through S4, and all get a 63.1° headtube angle; reach numbers range from 420 to 488 mm, in roughly 23 mm jumps between sizes. The stack height jumps by nearly 10 mm per size, starting at 631 mm on the S1 and growing to 658 mm on the S4.
Things get more unusual when it comes to the chainstay length. Like a lot of modern bikes, the Supernought gets size-specific chainstay lengths, but Forbidden has kept their trend of doing much bigger jumps between sizes than most brands. The S1 Supernought starts at a quite-short 431 mm, and each size gains about 15 mm, up to a colossal 475 mm chainstay on the S4 size. Swappable dropouts allow for +/- 10 mm of adjustment on all four sizes. That all adds up to wheelbases ranging from a not-super-long 1,212 mm to a very-roomy 1,336 mm (in the neutral dropout position). Forbidden’s take on chainstay length is that the big steps they offer make for a consistent ratio of front to rear center across the size range, and more similar handling between the different sizes as a result. The math checks out, but it’s notable that Forbidden is going for such big jumps between sizes when three to six millimeters is more common. We’ll be chatting with Forbidden founder and engineer Owen Pemberton over on Bikes & Big Ideas, so stay tuned for a lot more on their design philosophy and approach to geometry, coming soon.
