2018 Transition Sentinel X01

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NOTE: This is not a Vital Review, I am simply following the format, as I think it is well structured, and would like to use it to allow a common read of a review.

So a few weeks back Transition released a video detailing their new SBG geometry, (seen HERE) where they described how lengthening the top tubes, and increasing seat-tube angle can improve rider. But the thing that really peaked my interested was the last item integral to SBG, the reduction of fork offset from 56mm to a 44mm offset. As described in the video, this is suppose to improve stability and assist with cornering, as it forces the rider to weight the front wheel more.

With me being in the market for a new bike, and a newly released bike with all sort of new "standards" available for purchase, I had to go ride one to see what the hype was all about. So my buddy Stefan and I headed out to Transition HQ in Bellingham WA to demo the new Sentinel on a cold, snowy, November Saturday!

Transition Sentinel Highlights

• "Made for 29er haters" Although they are becoming harder to find these days
• 140mm of travel in the back 160mm travel up front
• Reduced offset fork: 44mm Fox, 42 Rock Shox
• Horst Link Suspension (FSR)
• Internal cable routing
• Water bottle mount
• Molded rubber protection
• Enduro max sealed bearings
• Trunion mounted shock
• Boost spacing 110mm front 148mm back
• Three build kits available: X01 ($4999), GX ($3999), and NX ($2999) - Frame only ($1999)
• Four Sizes S, M, L, XL
• Weight - Not sure but, how many people really care about this these days?

Geometry

The Sentinel's geometry looks very, very aggressive on paper, with a extra long amount of reach, a 64 degree head angle which is the same as my old Banshee Ledgend MKII, and an enormous wheelbase. However once riding, it feels much more reasonable - further details below.

I stand at about 5'6" tall, which puts me firmly between a small and medium sized frame with most manufacturers. Liking a tad more reach has me generally size up to accommodate that, where prior bikes I've owned have all been medium frames. Comparing the geometry charts to those other bikes to the Sentinel makes the effective top tube length on the Sentinel seem, very large. So much so, that I was prepared to only look at a size small. I reached out to Transition to confirm this theory, where I was actually told to stick with a medium size. Once sitting on the medium Sentinel, it became apparent that it was in fact the correct size, and felt comparable in reach to my Spartan. Moral of the story is, if you are a bit confused, ask for some help.

On The Trail

Stefan and I picked up the Sentinel's on the first weekend they were available for demo from Transition. The prior day, Bellingham had received about 4" of snowfall, and temperatures were hovering around mid to low 30's throughout the day.

We promptly set the bikes up to our suspension liking and headed over to the extensive network of trails just outside of Bellingham called Galbraith Mountain. Sitting in the parking lot on the bikes one of the first things we was how comfortable we both felt on the bikes immediately, even with a "long" reach in the cockpit on paper, these bikes actually felt normal, if not slightly shorter than we were used to. I would state that for seated pedaling, I was less stretched than I was on my following.

Our ride started out with some single track climbing which included some tight switchbacks. This gave an excellent opportunity to test out an area I thought the Sentinel would be terrible at, slow speed maneuverability, to my surprise the bike handled them rather well, furthermore as the ride progressed the Sentinel did not feel long during slow maneuvering around flat corners. 

Now, even though it did handle those switchbacks well, I will be the first to say that this bike will not be winning any XC races. Pedal efficiency was good, but not nearly as snappy as others out there. However, over our three hour ride, I found myself quite happy with the suspension set in the "trail" or middle pedal setting on the shock, and it provided a great balance between support, and traction. Additionally, for a bike as supple as the it is, the Sentinel pedals far more efficiently than most. 

Pointing the bike down the hill really brought the soul out of the Sentinel, this thing is a bruiser. The slack head angle, and long chainstays encourage me to get up to speed and keep that speed over terrain. Even with snow on ground, traction in corners was superb, and momentum over rough roots and rocks made them seem as if they were not there, with the ability to plow right over them. Stating the word "plow" is intentional, as at speed the Sentinel like to settle in and roll over the terrain rather than pop and float like some other bikes on the market. 

Frankly it was mind blowing bringing this bike up to speed; the amount of stability provided while cruising at mach-3 was incredible and similar to that of the last downhill bike I've owned. I wish that we were able to have taken it on slightly more aggressive trails to better grasp the full potential and potential limit of the Sentinel. 

On jumps, the Sentinel feels balanced, and while airborne I never felt bucked or nose heavy coming off of a lip. 

In rhythm sections of berms, and jumps, the Sentinel carried great speed and traction, but would have benefited from slightly more suspension support in the mid-stroke, or slightly more low-speed compression damping, which is adjustable on the Fox DPX2 shock. 

Issues

While the one ride I have had on this machine was brief, there were some issues that did arise which could be cause for concern. 

The first was the water bottle cage position in the frame. In both the medium and large size frames we had issues fitting a full 26oz Purist bottle, without wedging into the cage. 

Another issue I noticed was the amount of dirt and debris which built up rather quickly on the top surface of the chainstay. Not a huge area of concern, as the area is fairly open to remove debris, but the buildup was more than I have experienced on other bikes. 

The last issue we both noticed, was on a fairly small ledge that was on the lower part of SST. It was a short 3' drop to flat, but created a harsh bottom out feeling in the rear end. The stock bike ships with two volume spacers in the shock, I would certainly add another to prevent this from happening in the future. 

Build Kit

We both rode the Sentinel X01 build, and we were really impressed with the spec. 

• The X01 drive-train worked flawlessly throughout the day
• Maxxis Minion DHF and DHRII provided ample traction, and would be a great choice of snow tire for your weekend ski trip. 
• E.13 TRS+ wheels offered great engagement while offering excellent lateral support. 
• 150mm travel Rock Shox Reverb!
• Fox 36 RC2 up front with Fox DPX2 rear shock
• ANVL Forge Stealth Saddle was... eh...ok, not my favorite but it got the job done. 
• But really the standout star on build of the Sentinel was the code RSC brakes. Wow these things are amazing! Super consistent, tons of power, and great modulation! 

All in all a really stellar build kit, which is hard to beat at a bike that retails for $5K. 

The Bottom Line

So who is the Transition Sentinel for? This may be for some, the only part of this review they read. 

In my mind, the Sentinel is for the trail/enduro rider who really likes to go fast down the hill where chunky terrain, and sustainable high speeds exist. Where the time taken to get to the top of the hill needs to be done efficiently but not at the highest priority. I've ridden in quite of few places and of those places, the Sentinel would be great in Santa Cruz, Southern Ca, and the PNW. Areas where the primary riding style is smoother easier climbs, but with fairly full-on descents. 

Additionally, the bike is not going to be for the trail or enduro rider who likes to pop and jump off of every feature in the trail. The longer length of the bike, made it more difficult to manual, as well as pick up and put down as other trail 29ers. 

Stefan and I wrapped up the day with a Party in the Woods IPA at Transition HQ with the thought of: "whoa this thing is a winner", and the Sentinel on the short list for a next bike. 

Conroy's Rating 

• Climbing: 3.5 stars - Very Good
• Descending: 4.5 stars - Outstanding
• Fun Factor: 4 stars - Excellent 
• Value: 4 stars - Good
• Overall Impression: 4 stars - Excellent

Ryan Conroy - Age: 29 // Years Riding MTB: 11 // Height: 5'7" (1.70m) // Weight: 165-pounds (75kg)

I am a mechanical engineer who loves to bike and ski. Growing up primarily in the Northeast where I rode trail bikes and raced DH back in the day, I recently moved to the Seattle area from Austin, where I typically ride Tokul, Tiger, and 27. My current favorite trail is B-Line.