Where to begin? I’ve been waiting a long time to throw a leg over a Transition Spire. It’s definitely my kind of bike — lots of travel, geometry that isn’t messing around, and looks that can kill. It’s also the big brother of my daily driver, the Sentinel. So it is just a slightly bigger Sentinel? Is it way burlier? Is it too much? Stick around to find out. 

Transition Spire Geometry

At the time I rode and reviewed the Sentinel it was the slackest bike I had ever ridden at 63.6 degrees. The Spire is here to set a new precedent. At 62.5 degrees in the low geometry setting, it is now the new slack king. When the Spire first launched last spring, I looked up the results from the previous World Cup DH season. The Spire was slacker than the average winning bike. But, Transition has a way of making long and slack feel a lot more manageable than it looks on paper. They did it with the Sentinel, did they do it again with the Spire?

Other key geometry numbers include the 1325mm long wheelbase and 510mm reach in a size extra-large. It also has size-specific chainstays with sizes S-L getting 446mm long stays while the XL and XXL get 452. Those are some long chainstays across all sizes. I’m a tall guy and prefer a longer rear center so I don’t hate seeing those numbers — shorter folks might. 

The Spire is compatible with both coil and air shocks as well as single and dual crown forks for those so inclined. 

Transition Spire Review

Uphill

I purposely don’t read other bike reviews before I’ve ridden a bike. I don’t want to fill my head with others’ thoughts and opinions before I can form my own. That’s why I was caught off guard by how well the Spire pedals. After writing and filming this article I looked up what other sources were saying about the bike, and it seems like most everyone is on the same page about the Spire going uphill way better than it should. Hopefully, that’s the new trend for enduro bikes. I felt the same thing with the new Santa Cruz Megatower.

The first thing I noticed with the Spire was the lack of inefficiency. That’s a brain twister — the bike is efficient. It pedals well, not just for the category, but I’d say across the board it has a good pedaling platform. It doesn’t feel all that much slower than the Sentinel. The Spire doesn’t have a lot of pedal bob and it certainly doesn’t feel like you’re pushing a 40lb wheelbarrow up a hill. I’ve done a fair bit of riding in the PNW, where this bike is designed, and a lot of the climbing there is up stupid steep logging roads. The Spire is going to do well there, no doubt. At home, most of my climbs tend to be on singletrack, some of them can get a little technical. The bike is a little long for stuff like that, but I didn’t feel that it was too unwieldy. The trail I filmed the video review on is rather punchy, tight, and twisty on the way up. I didn’t struggle more than on other bikes. 

The conditions on the day I filmed were probably among the most challenging climbing conditions for a bike — snow, wet rocks, slimy roots, patches of slick dirt. The Spire handled them well. You can’t really fault the bike for sliding out on diagonal roots when your tires are packed with slushy snow. During the rest of my riding, I had much more favorable conditions where the Spire showed off how much traction its suspension can generate.

The climbing position feels very neutral. The reach might be 9mm longer than the Sentinel’s, but the steeper seat tube angle works to offset that too stretched out feeling. I felt upright and comfortable, with my weight balanced between the wheels. I think that has a lot to do with how much control you have over the bike on technical uphills. You’re not so far off the back of the bike that you can’t control the front wheel and conversely, you’re not so stretched out over the front that you don’t have room to move. You do feel the overall length of the bike on tight corners, but because of the riding position, you’re able to control it fairly well. 

Overall, the Spire goes uphill much better than it has business doing. I’ll put it right up there with the new Megatower.       

Downhill

This is where things get really fun. I mean the downhill is really fun on any bike really, but it’s a damn good time on the Spire. Let’s use our imaginations for a minute. Close your eyes and think of what a slack 170mm bike should feel like as you’re blasting through a steep rock garden to a tight catch berm at the bottom. Open your eyes and look at this picture of the Spire. Because this bike is the closest thing I’ve ridden to having that “I’m Loic Bruni!” feeling. 

I mentioned earlier that the Spire is the slackest bike I’ve ever ridden, but Transition has a way of making their bikes not feel too unwieldy. I think it all has to do with their suspension design. They combine a lively suspension feel with some of the rowdiest geometry around for a pretty unique ride feel. The Spire’s suspension is what works the magic to keep the bike feeling agile and fun. While the bike is very stable, it doesn’t feel like the earth’s gravity is working double-time to keep it on the ground. It unweights with ease, whether to jump, bunnyhop, change lines, or just goof around. It takes a bit of effort to get the front wheel off the ground because the bike is so long, but the suspension isn’t compounding that effort by being overly dead and mushy. 

The Spire feels incredibly smooth through the rough. I think a lot of it can be attributed to the suspension, but I would say the lion’s share comes from the geo. The wheelbase is “too long to fit in a bike bag” long which keeps the bike stable at speed, no matter how rough things are on the ground below you. Combine that with a slack front end that keeps you from seeing yourself out the front door, and you’ve got long-term relationship stability. Nothing seems to be able to knock it off course. 

The bike obviously craves, steep and rough. It is at its best at high speeds in terrain where high speeds shouldn’t be a thing. Its aggressive nature starts to become apparent on flatter sections of trail. In places where I can normally carry speed without having too much effort, I found myself throwing in a couple of pedal strokes. Maybe that’s because it always wants to go faster, but I think it’s due to the bike needing a little extra effort when gravity is doing the majority of the work for you.  

Transition Spire Comparisons

Transition Sentinel

Is the Spire simply the Sentinel’s big brother? Yes, it’s exactly that. Take the Sentinel and shift it up the scale a few notches. It still has the “more fun than it should be” quality but it’s that much more capable on the downhills. I don’t think there’s a huge climbing penalty if you go with the Spire. You’ll mostly see the drawbacks to the bigger bike on mellower descents and flatter terrain. The Sentinel does a better job of being fun and lively when you’re not at the ragged edge. I’d choose the Sentinel if I wanted a more well-rounded bike. I’d pick the Spire if I found myself on rugged terrain for the majority of my riding.   

Santa Cruz Megatower

The new Megatower landed in the sweet spot for me. It’s aggressive and burly, but when you don’t need all that travel, the bike doesn’t penalize you too much. It is one of the more well-rounded enduro bikes I’ve ridden. The Spire isn’t quite as mellow-terrain-friendly as the Megatower, but I think it’s slightly more composed in the rough. If the Spire is shifted two to three notches up the burly scale from the Sentinel, the Megatower is only two. These bikes are so similar in ride feel that it’s tough to take one over the other. I’d close my eyes, throw a dart and be happy with either one. They each have their pros and cons and it’s just going to come down to your priorities. 

Norco Range

The Norco Range has a way of changing your mental state the second you throw a leg over it. The bike feels overbuilt, huge, and forgiving. It has you trying stupid lines and going faster than you thought humanly possible. It’s not a great climber or really all that good on easier terrain and it can take a heavy hand to get it to do anything but fall downhill in a straight line (but it’s really good at doing that.) The Spire is a much more approachable ride, but it doesn’t have quite the same effect on your mental state. I will say, it’s an easier bike to just pick up and ride. It goes uphill better and handles turns and mellow terrain better. I’d pick the Spire if I climbed to the top of my fun and gnarly descents. I’d take the Range if I did more shuttling or lift access.  

Who is THE Transition Spire for?

I’m not going to say the Spire is a well-rounded option for anyone looking for a do-it-all bike. It’s a little too aggressive for that. If that’s what you’re looking for, check out the Megatower, Sentinel, or Rallon. If you’re looking for an enduro bike whether to race, take to the bike park, or search out the roughest trails, the Spire is a great option. It’s going to handle all of the gnarly stuff just fine without being too big of a chore when Zach calls you to go for a long pedal.

I see it as a really good bike for folks who not only want to survive the rough trails but want to start actually riding them. They’re looking for extra speed where others are clinging to the brakes for dear life. The Spire has the same attitude — it wants steeper, faster, and rougher.

One-Line Transition Spire Review

The bike you picture when you think of smashing through a rock garden with 170mm of travel.