Transition trends beyond the Sentinel with its new Spire 170mm enduro bike, featuring very bold angles.

If Transition’s Sentinel isn’t enough bike for you the Pacific Northwest brand has a new enduro 29er.

For those riders who believe in progressive geometry and lots of suspension travel, the Transition Spire will be ideally configured.

Read more: the best enduro bikes 

Spire is slacker than some downhill bikes

With 170mm of travel at both wheels, the Spire is designed for those exceptionally steep and exceedingly technical descents. This is now the longest travel single-crown fork bike, in Transition’s product portfolio.

Riders have the option of both aluminium and full-carbon frames, with the new Spire, and there are some interesting design details, such as the 1.5” head tube. This should allow Spire owners the latitude to use angle sets, if they wish to go beyond Transition’s production geometry.

Read the specification chart and you can’t imagine who would need to slacken a Spire. The standard head angle is 63°, with a flip chip that can trim that down to 62.5°, bringing it into the downhill mountain bike realm. Reach on a size large Spire measures out to 485mm and Transition is offering sizing through S to XXL.

Transition has also been mindful of the influence that chainstay length can have on overall enduro bike stability and agility. The size S, M and L Spires use a 448mm chainstay, which stretches to 454mm on the XL and XXL versions.

Compacts cranks for all sizes

Spires run a 170mm fork with 44mm of offset and Transition’s factory build options use 165mm cranks for all sizes. Considering the terrain that riders on a 170mm enduro might venture into, those short length cranks should reduce the probability of rock strikes.

The presence of a threaded BB and Enduromax bearings should also reduce the maintenance burden and cost, of running a 170mm enduro bike such as the Spire.

Transition is marketing the aluminium frame for £2,199.95. If you want that in carbon, it will be £3,299.95. Aluminium builds start at £3,699.95 and the most affordable carbon version is £5,799.95.