The 170mm Transition Spire 29er Has the Second Longest Travel in the Lineup

The all new Transition Spire is a long-travel 29er with a low bottom bracket height and a flip chip for mixing wheels.

The folks at Transition Bikes clearly weren’t satisfied with the gap between their 150/160mm Sentinel 29er and the burly 200mm TR11 downhill ride. They fill that slot today with one fun-looking gravity machine called the Spire. This new 29er smooths the trail with a balanced 170mm of travel front and rear, and it’s rated to play well with a dual-crown fork if that’s your jam. It’s also available in full carbon or aluminum, with two color options for either material. All of the frames are compatible with a 27.5″ rear wheel by flipping the chip into the high position, and owners can decrease the rear travel to 160mm by reducing shock travel by 5mm.

Transition didn’t share the full spec and pricing quite yet, but all of the bikes will wear a pair of Schwalbe tires, a OneUp dropper post, suspension from Fox, Marzocchi, or RockShox, and 165mm cranks across the board to prevent rock strikes.

Coil and air-sprung shocks should work fine on the Spire, thanks to its 23% progression through the travel.

Like the new Patrol, the Spire uses shorter 448mm chainstays (low position) on the small, medium, and large frames, and 454mm legs on the XL and XXL sizes. The BB drop is significant, at 32mm in low and 25mm in the high setting, providing those shorter 165mm cranks with some clear justification. Getting the Spire up a hill will be cozy given the steep seat tube angle that decreases from 79.1° to 76.6° across the size range when set in the low position. Reach measurements spread across 425, 455, 480, 505, and 530mm, with short seat tubes that should allow riders to select their bike based on reach instead of their leg length.

As usual, the rear brake is routed externally on all frames to ease the bleed process, while all of other housing and hoses are run internally. The boost axle spacing follows a threaded BB, and the linkage should move smoothly for quite a long time on the Enduromax sealed bearings.