Guaranteed to put a massive smile on your face every time you take it for a blast

MBR Test Winner

Product Overview

Overall rating:

Score 10

Calibre Bossnut mountain bike


  • Fast, fun and very capable


  • None that we can think of


Calibre Bossnut (2016) review

Price as reviewed:


Buy Now: Calibre Bossnut mountain bike from Go Outdoors for £1,100!

Last year, Go Outdoors took everyone by surprise when it launched a new full-suss trail bike with thoroughly modern geometry and incredibly keen pricing. Twelve months on, and with stiffer competition, we’ve got the 130mm-travel Calibre Bossnut back in the mix to see if it’s still top dog in the £1k class.

>>> Click here to find the best cheap mountain bikes

Being a relatively new design, the Bossnut hasn’t changed one jot for 2016. You still get a top-notch frame design and blinding specification — a combination that delivers a level of ride quality previously unavailable at this price point.


And while we are on the subject of price, we should point out that you need to sign up for the Go Outdoors discount card to slash the list price from £1,299.99 to £999.99. Given that the discount card only costs £5, and can be used when buying other items from Go Outdoors, it’s money very well spent.

Just like Boardman, Calibre only offers the Bossnut in three frame sizes. Unlike the Boardman, however, the dimensions are a little more generous on the size Medium Bossnut, so we didn’t automatically feel the need to go for the biggest frame size. This is great news for anyone either side of 5ft 10in, as taller and shorter riders can also benefit from the Bossnut’s killer ride quality.


With RockShox taking care of suspension duties, it was relatively easy to get a balanced set-up on the Bossnut. All we had to do was run the Sektor fork at the higher end of the recommended pressures printed on the back of the fork lowers, and run the rebound adjusters fully open on the fork and shock.

Monarch shock rules this test, but it’s just a touch too slow

Monarch shock rules this test, but it’s just a touch too slow

The rear suspension on the Bossnut has just the right amount of ramp-up to stop it bottoming on big hits, and while the rebound damping is very controlled, it’s probably a bit too slow for lighter riders running lower shock pressures. Still, it’s reassuring to have household name suspension components, just in case anything goes wrong or needs servicing. It also means you can get the shock custom tuned if you are outside the useable range of adjustment.


The cockpit on the Bossnut places you in a very commanding position, but there’s room for a slightly shorter stem. Other than that, there isn’t a hair out of place. The one-finger Shimano brakes are on par with Shimano’s higher-end XT units and, if anything, the simplified lever design offers a smoother, more controlled action that results in better modulation.

Plain vanilla brakes from Shimano, but delivering power and modulation

Plain vanilla brakes from Shimano, but delivering power and modulation

Tyre-wise, the meaty 2.3in WTB Vigilante up front gives maximum grip and confidence, while a shallow tread Bee Line 2.2in on the rear helps save your legs by reducing rolling resistance. The lower profile rear tyre also means you can tap the rear brake and snap the back end around super tight switchbacks with ease.


Stand up to sprint and the Bossnut responds with instant acceleration. On the gas it’s lightning fast, so even though it’s not the lightest bike in this test, you can still demolish the steepest climbs with ease.

WTB’s Vigilante does justice to the Bossnut, dishing out a ton of grip

WTB’s Vigilante does justice to the Bossnut, dishing out a ton of grip

On faster trails, like those found at BikePark Wales, the Bossnut never faltered. It felt more solid than either the Voodoo or the Boardman and, with geometry more closely mirroring the numbers found on modern enduro race bikes, the only limiting factors here are rider skill and courage. In fact, we’re so confident in the Bossnut’s capabilities, we’re convinced that it would be a competitive enduro race bike. It really is that good.

Sure we’d like to be able to run the rebound on the suspension a touch faster to give the bike some pop, and having the option to speed up the shock would definitely make it easier for sub-70kg riders to achieve an optimum suspension set-up. As is stands, the rebound on the RockShox Sektor fork and Monarch R shock both benefit heavier, faster riders.

  • A Shadow Plus stabilising rear derailleur helps keep the chain on and silences chain slap
  • The WTB Volt saddle and comfy lock-on grips give the Bossnut the best contact points on test
  • The combination of a tapered head tube and RockShox Sektor fork provides accurate steering
  • Shimano’s two-piece chainset with external BB cups is bomber solid




Bike tech, geometry and sizing are always evolving, but with cutting edge geometry and a build kit that rivals similarly priced hardtails, the Calibre Bossnut is still well ahead of the development curve. For a penny shy of a grand, the price tag is certainly entry-level for a 130mm-travel bike; the ride quality however, is anything but. From local lunchtime loops, to bike park blasting, the Bossnut proved time and time again that it’s a trail bike without compromise. It’s not just about going fast, however, it’s also guaranteed to put a massive smile on your face every time you take it for a blast.


Frame:Calibre aluminium, 130mm travel
Shock:RockShox Monarch R
Fork:RockShox Sektor Silver, 130mm travel
Wheels:Shimano Deore hubs, WTB Sti 23 rims, WTB Vigilante/BeeLine 27.5x2.3/2.2in tyres
Drivetrain:Shimano Deore chainset, mechs and shifters
Brakes:Shimano Deore, 180/160mm
Components:Ritchey 760mm bar and 70mm stem, WTB Volt saddle
Sizes:17.5, 19.5, 21.5in
Weight:14.5kg (31.97lb)
Size tested:19.5in
Head angle:66.1°
Seat angle:74°
BB height:342mm
Front centre:727mm
Down tube:673mm
Top tube:595mm