Review | The Calibre Sentry is a wallet-friendly enduro bike

For a brand that didn’t even exist five years ago, Calibre Bikes has shot to stardom pretty darn quickly. In its short history, the company has been breaking new ground in the mountain bike market with its mix of low-cost high-performance bikes, with the popular Bossnut full suspension bike leading the charge.

This £999 full suspension bike has been collecting awards from the industry since its first release and even managed to earn the coveted Singletrack Readers award in 2018. The Bossnut’s success meant Calibre had the confidence to release the Triple B version of the Bossnut and the Beastnut – bikes with the same award-winning frame, only built with more upmarket components.

The Bossnut and its variants remain popular trail bikes, but what about the customer who has outgrown the speed and performance of the OG Calibre full-suspension bike? What about the customer looking to hit the trails harder, faster and further? Riders who could perhaps benefit from more travel, more progressive geometry and larger 29er wheels?

Calibre’s answer is this, the all-new Calibre Sentry, a bike that the Calibre team reckons you could buy at the store, build in the carpark and race in the EWS on.

There are two specification options. Our test bike is the entry-level Sentry and costs just £2,000. For customers really serious about racing there’s also a Sentry Pro built with go faster red Lyrik RC2 forks, Super Deluxe Coil shock with remote, SRAM GX Eagle and a £2800 price tag. Calibre is so confident that the Sentry Pro is EWS ready that they’ve sponsored Chloe Taylor who will use an off the peg bike to race the 2019 EWS season!

At £2,000, the Calibre Sentry comes is up against comparable bargain big travel bikes like the Canyon Torque AL 5.0 (£1,999), Commencal Meta AM 29 Ride (£2,128), and the YT Capra 29 AL Base (£2,299). The difference between those three bikes and the Calibre though is that the Sentry is available in store in most major towns where you can physically see it. It also has larger wheels than the Torque, and it’s notably cheaper than both the Commencal and YT.

Right, let’s take a closer look at the Sentry’s key ingredients.

Video: Calibre Sentry First Look

Calibre Sentry Review – The Bike

Whereas the Triple B and Beastnut used the same frame as the Bossnut, something else was needed when creating the Sentry and Calibre started with a fresh pad of paper, a new drawing board and a handful of box-fresh 2H pencils to come up with this.

6061 T6 aluminium tubing is used for the mainframe, and rear triangle. The two structures are bolted together with custom CNC machined alloy linkages running on sealed bearings to give the Sentry 150mm of rear wheel travel via a RockShox Deluxe R air-sprung shock.

So far so good and so far so normal, but take a good long look at this geometry chart;

It’s not uncommon these days to come across a modern 29er enduro bike following the on-trend long, low, slack recipe, but Calibre has really gone the whole hog with the Sentry.

Reach figures on this all-new bike range from 445mm on a small (yup a small!) up to 506mm on an XL frame. Long reach is combined with a short seat tube length across the entire size spectrum for ample standover giving customers plenty to think about when choosing the appropriate size but it also means that riders normally stuck between sizes can easily size up.

With long and low sorted, Calibre needed to check the slack tick box, and it’s done so with a 64° head tube angle. Also of note is the short 42mm fork offset, which is there to add further stability to the front wheel when riding flat-out down steep trails.

A 76° seat tube might not be as steep as a Pole, but it’s enough for a comfortable seated climbing position and ensures your saddle is well out of the way once that Kore dropper is activated.

At 178cm I tend to find myself sitting right between a size medium or large bike, and as brands chase that geometry dragon I find that I seem to be forced toward a large. With a reach of 465mm though, a medium Calibre Sentry sits slap bang in my happy place. If I was more interested in jumping and playing around in the woods then I might even consider a Small.

Looking at the Calibre Sentry’s frame details we find external cable routing throughout, which saved Calibre some money when building the bike and will save you a lot of time if you ever need to change a cable or hose.

Cable and hose routing is neat, with plenty of zip tie locations to keep any excess in check, there are even neat cable mounts on the suspension linkage.

There’s Boost spacing, a bolt thru axle and a really neat inboard rear brake calliper mount. All great features on any bike, but especially impressive on such an affordable complete bike.

Complimenting that 150mm of RockShox controlled rear travel is 160mm of front wheel travel via the RockShox Yari RC fork. RC means we have a Charger damper, rebound control and compression adjustment, but for the serial upgrader, the Yari also means the same chassis as a Lyrik and the possibility of fitting an upgraded damper at a later stage.

A 45mm Calibre branded stem holds the 800mm Kore Duroc handlebar, which is plenty wide enough and has markings so you can neatly chop them down to your preferred width if required.

Those wide Kore bars are also the perfect place to attach a set of SRAM Guide RE brake levers. I really like the length and feel of the SRAM lever blade, especially when fitted to a set of four-pot callipers. The Guide RE levers don’t have the same adjustment as more expensive Guide options, but they still offer great control.

SRAM gets even more screen time thanks to a SRAM NX Eagle 12-speed shifter cabled up to a matching NX Eagle rear mech to slide an NX chain across the 11-50t NX cassette. That cassette is a monster, in more ways than one. It offers plenty of gear options, but it also weighs in at a whopping 613g, more than a GX Eagle and more than a similar 12-speed SunRace option.

Calibre has matched the rest of the drivetrain to a SRAM chainset, but this is an NX Eagle Power Spline model with old skool internal bearings instead of the external cups we’re more used to seeing. It’s one of the only obvious cost-cutting measures on the bike but hasn’t caused problem or concern during our test period.

For those moments you’re not smashing the ruts, there’s a Calibre Sentry branded saddle to perch on. It’s nothing special but it is very comfortable with plenty of padding. Beneath the generic saddle is a Kore Mega Stealth dropper post. This stealth routed dropper offers 150mm of travel but with the shorter seat tube, a longer drop might be necessary for taller riders.

The Kore Mega Stealth is cable operated and has an over bar lever, not my preferred choice and something I’d swap out pretty sharpish.

Last but not least are the wheels. Calibre is pretty proud of the fact that they’ve managed to spec the Sentry with quality WTB tyres with tough casings. We have a 2.6in Vigilante TCS G2 Tough Grip 2.6in in the lead and 2.4in WTB Trail Boss G2 high grip in the rear. Each WTB tyre is mounted to a WTB ST i29 TCS rim that’s laced to Boost Formula hubs.

Phew, that’s the lot! So how does it ride?

Calibre Sentry Review – The Ride

If you know your numbers then you’re not going to be too surprised to learn that the Sentry is especially potent when pointed down a hill. Calibre’s desire to push the geometry envelope to the next level makes for a stable and confidence inspiring ride that will please not just newer riders hoping to hone their skills, but seasoned riders too.

The medium sized bike I tested was super easy to get over the bars on and weight up that chunky 2.6in tyre and let it dig into loose dirt and loose turns. The overall length of the bike means you’ll need to shift your body around quite a bit more than you would on a smaller lighter bike, but these are skills that need learning anyway, and any bike will benefit from being ridden in this manner.

Steep chutes are a walk in the park on the Sentry. Again, it’s the modern geometry that really helps this big bike tackle those stupid descents you know you shouldn’t really be on and it’s in these situations that you’ll appreciate Calibre’s decision to spec Guide RE brakes.

Those powerful SRAM anchors come into their own when the speed picks up too, and it will pick up, quickly. With 160mm of travel up front, 150mm in the rear and a pair of hard-hitting wheels wrapped up in heavy duty rubber, you will be hitting rocky trails much harder than you might have before, and you’ll be covering ground at a seriously increased rate of knots.

Although a big travel bike, it was on the fast flowy, smoother trails that I really felt the Sentry get up and go. We have a fun track close to the office that’s not too steep, not too lumpy, but really flowy and fast, that requires you to keep on your toes and switch direction turn after turn after turn.

Going into the trail I thought the Sentry might be a little too much bike for this flat-out flowy trail, but it really came alive and encouraged me to lean over further, dig the tyres in a little more, and pump through corners to pick up more and more speed. Pretty impressive for a long-travel bike that weighs 36lbs.

Ah yes, the weight. 36lbs (16.36kg) is heavy but a few small upgrades and changes could bring the weight down quite a bit, and remember that some of that weight is in those tough, wide, grippy tyres. Going tubeless would be my first upgrade and I might even consider a lighter cassette at some point too, but really you don’t need to get too hung up on it.

The only times I really struggled with the heft of the Sentry was on long, steep, uphill slogs, the ones that start at the very beginning of the ride and end about 20 minutes later. The Sentry has a decent seat tube angle and a massive Eagle cassette, so it has the goods to get you where you want to go, you’ll just get up there a bit slower.

Bottom line, a little slow on the up, blazing fast and fun down, just the way I like it.

Calibre Sentry Review – Durability Notes

The only issue I have run into is with the Kore dropper post. After the bike was used on a particularly wet and rainy day the post decided it no longer wanted to drop. A strip, clean and lube solved the issue to an extent. It drops and extends still, but it certainly doesn’t sound or feel as smooth as it did when new. I’ve also experienced the main pivot bolt becoming slightly loose, but once tightened it has stayed put.

Everything else has worked flawlessly and even the NX Eagle drivetrain has played much nicer in the dirt and mud than early versions of the drivetrain did. I’ve not even had a puncture thanks to those burly tyres.

3 Things That Could Be Improved

1. I would convert the Sentry to tubeless at the store, a service Calibre will be offering
2. I would certainly change that dropper remote to something like a PNW Loam lever
3. Our dropper post became sticky and noisy after just one very wet ride. This is my first time trying a Kore post so I don’t know if it’s a common issue or not, but it is something that you’ll want to keep your eye on

3 Things That We Loved

1. We say a lot of bikes feature progressive geometry these days, but for £2,000 there are few bikes which really push the geo figures as much as the Sentry does. If you’re on a budget but want a next-gen LLS (long, low, slack) bike, there are few more progressive than the Sentry
2. It’s clear that Calibre put a lot of thought into the Sentry’s frame, construction and geometry, but they’ve also been really smart with the componentry too. Although heavy, the heavy-duty WTB tyres haven’t let me down. The Yari offers the same chassis as the more costly Lyrik, the bar is a full 800mm, there’s a stealth dropper as standard, brakes are powerful 4 pots, the list goes on. It’s not only affordable but smart
3. Understated looks make the Sentry look very classy

Calibre Sentry Review – Overall

If you’re in the market for a long travel 29er with up to date geometry, but you’re on a strict budget, the Sentry should definitely be on your short list. Yes, there are similar 29er bikes at around £2300, but those are direct to consumer bikes and the chance of seeing one in the flesh before buying is going to be pretty rare.

It’s clear from speaking to the guys at Calibre and riding their latest bike, that a lot of thought and energy has gone in to building a high-performance chassis and building the bike within a budget that will still allow riders to hit the ground as hard as the geometry warrants, and they’ve really succeeded.

Yes, the Sentry is a heavy bike but that’s partly due to the cost constraints but also due to those reliable heavy duty tyres and cost-conscious NX Eagle drivetrain. You could save quite a bit of weight by simply going tubeless and switching the NX cassette to a lighter one from SunRace.

The Calibre Sentry is fast, stable, and confidence inspiring, just the characteristics you want from a bike egging you on through and EWS stage.

Calibre Sentry Specifications

• Frame // 6061 Alloy 150mm travel. 148 x 12mm.
• Fork // RockShox Yari RC 160mm 42mm offset.
• Shock // RockShox Deluxe R 230 x 62.5mm
• Hubs // Formula sealed bearing Front 15mm, Rear Formula 12mm.
• Rims // WTB ST i29 TCS 2.0.
• Tyres // WTB Vigilante TCS G2 Tough Grip 2.6in Front, WTB Trail Boss TCS G2 Tough High Grip 2.4in rear.
• Chainset // SRAM NX Eagle Power Spline 32t chainring.
• Rear Mech // SRAM NX Eagle.
• Shifters // SRAM NX Eagle.
• Cassette // SRAM NX Eagle.
• Brakes // SRAM Guide RE 4 pot 200mm rotor front, 180mm rotor rear.
• Stem // Calibre Trail 45mm.
• Bars // Kore Duroc 800mm wide, 20mm rise.
• Seatpost // Kore Mega Stealth 150mm dropper.
• Saddle // Calibre Sentry
• Size Tested // M
• Sizes available // S,M,L,XL
• Weight // 36lbs
• Price // £2000

Review Info