The Bossnut is back! Calibre’s bargain bouncer goes 29

by 23

After a total of five incarnations as a 27.5in bike, the new Calibre Bossnut rolls out on 29in wheels front and rear. And a bit more travel to boot.

2025 Calibre Bossnut in a nutshell

  • 29in wheels front and rear (XS is 27.5 F+R)
  • 135mm rear travel (up 5mm)
  • 140mm fork travel (up 10mm)
  • 64.5° head angle
  • 78° effective seat angle
  • Bottle bosses and 2 x accessory bolt pairings
  • Dropper post as standard
  • Shorter seat tubes
  • Longer reach
  • RockShox suspension
  • Shimano Cues 10sp drivetrain and MT401 brakes
  • Five sizes: XS, S, M, L, XL
  • SRP £1,499 with GO Outdoors discount card
Our demo bike was something of a Trigger’s Broom in terms of wheelset/tyres!

Let’s start with the end, as most of you will just want to know what it rides like. You’ll have to wait for a proper review until we get hold of final production bike but in the meantime I’ll fire out a few First Ride thoughts…

My overriding thought is that the new Bossnut is way better than any of the previous 27.5 Bossnuts.

Not (just) because it has grown-up size wheels at last, but more that it has geometry that doesn’t feel like it’s outdated (or about to be imminently outdated). The previous Bossnuts always seemed to get something of an easy ride in terms of reviews, almost purely due to the value proposition in my opinion. They were amazing VFM. But they never actually blew my mind when it came to the actual riding.

Having said that, I think the smaller sized Bossnuts were fine for their pilots. Us lanky riders weren’t so lucky. Too short (front rear and rear centre) and too slack in the seat angle department.

The new Calibre Bossnut is leaps and bounds better in terms of geometry. This XL size has a proper reach (500mm) but doesn’t have the skyscraper (530mm) seat tube of yore (it’s now a tidy 460mm). The head angle is more capable 64.5°. The steeper (78° claimed effective) seat angle and longer (445mm) chainstays make it immeasurably better not just as a climber but as an all-round mountain bike.

Another general improvement is in the controls and contact points. The shifter is lovely. The grips and saddle are nice. The dropper post… well, for a start there is one. And the L and XL droppers are 170mm, which is acceptable. The dropper remote is a proper job. The Shimano MT410 brakes are fine (if you don’t look at them – they ain’t pretty).

In terms of performance and capability, the new Bossnut impresses. We’ve been spoiled by high end brakes and tyres, so that took a bit of getting used to. But get used to it we did and the Bossnut got up, along and down everything we pointed it at.

The rear suspension felt a whole lot more active and usefully grippy than I remember the old Bossnut being. This is principally more due to RockShoc upping its entry level shock game than anything.

As mentioned, we’re due a proper production version of the 2025 Calibre Bossnut any day now. And we can’t wait to see what it can really handle. In the meantime, here’s some Press Release ‘n’ piccies stuff…

BOSSNUT 2025

The name Bossnut needs no introduction in the mountain bike world.

Since its launch in 2015 the Bossnut redefined what an entry level full-suspension bike was capable of.

It won countless awards and became the benchmark which other brands entry level full-sus bikes were measure against. If you wanted to get into mountain biking and didn’t have a huge budget then the Bossnut was the bike to buy.

The Bossnut quickly gained a reputation as the go-to bike for new riders or people getting back into the sport.

This sums up Calibre’s ethos of producing bikes that provide affordable performance.

The original bike went through 5 iterations and continued to grow in popularity until 2020 when due to covid our production ceased. It’s been over 4 years since the last model launched, 4 years of redevelopment, testing and refining to create what we believe to be the best entry level performance mountain bike on the market. The bike that your mate who is into Mtb will recommend to get you hooked and become one of us!

The original Bossnut built a cult-like following, what became clear to us was that people loved their Bossnuts in the same way that VW Transporter owners love their Bus. They want to upgrade them, personalise them and show them off.

This meant that the new bike needed to be built around a solid frame that would be worthy of the upgrades that people make and not just get them into mountain biking but join them on the journey and stand the test of time.

So what’s new?

The Bossnut has always been a short travel trail bike that is designed to be fun to ride above anything else. The updated geometry makes the bike more capable than ever but it also keeps it’s playful poppy feel.

The biggest change to the bike is that it is now rolling on 29” wheels. We tested 27.5”, 29“ and mullet versions of this bike and the 29er came out on top making the bike feel confident, fun and fast rolling.

The travel has also been increased from 130mm all round to 140mm on the front and 135mm on the rear making the bike an even more capable all-rounder that can take the bigger hits as your riding progresses.

We have seen how hard the previous generation bikes got pushed, from UK enduro racing to alpine seasons so we have made sure that the new bike is built to last. We developed a chunky custom tubeset and redesigned the forgings to strengthen every part of the frame. We have had our riders absolutely hammering them and nobody has managed to break one of the new frames. We have also taken care of the details, we’ve got space for a bottle cage inside the frame, improved cable management and added bosses for tool storage under the toptube. We’ve also gone for Boost spacing on the hubs adding stiffness and keeping the frame futureproof.

One thing that the original Bossnut didn’t have was a dropper. It’s now hard to imagine riding a trail bike without one so we have spec’d the bike with a size specific dropper with a solid alu lever out of the box.

Geometry and sizing

Screenshot

Bossnut customers span a massive age and size range and it is important to us that it is accessible to everyone. The new bike now comes in 5 sizes. The Small to XL sizes come with 29” wheels and the XS bike for teenagers and smaller riders comes with 27.5” wheels.

We’ve got a slack 64.5 degree head angle for stable descending, a steep 78 degree seat angle giving a composed climbing position, a low BB for a planted feel in the corners and a low standover for manoeuvrability. A shorter seat tube length across all the sizes gives riders the option of sizing up if they prefer a more stable bike with a longer reach and sizing down if they prefer a shorter more nimble bike. We have 170mm droppers on the L & XL sizes, a 150mm on the M bike and 125mm on the S & XS bikes.

Components

We think that your first mountain bike can get you hooked on riding. Creating a bike that makes riding fun and accessible has always been the priority with the Bossnut. Finding the right balance of components that will keep the bike at a price point but perform at a level that makes no excuses or compromises when on the trail.

As always the suspension is taken care of by Rockshox, a 140mm Rockshox Recon RL fork up front and a Rockshox Deluxe Select shock on the rear. They are simple to set up and work together with the linkage to give an active and composed ride feel.

The brakes are Shimano MT401 with 180mm rotors front and rear. These give excellent stopping power and a comfortable and consistent lever feel. The drivetrain is also taken care of by Shimano. The brilliant new Cues 10 speed set up offers a wide range 11-48 cassette is built for longevity and shifting under load. We’ve gone for Maxxis tyres with a grippy Minion DHF up front and a fast rolling Forkaster on the rear. These are seated on 30mm internal tubeless ready rims.

Things that matter

The Bossnut is and always has been a bike that strives to give the rider the best experience possible.

The bike is designed around the things that make genuine performance differences when you are on the trail. The past four years has been an amazing journey, designing and refining the frame and testing lots of components. The result is what we think gives the right balance of what matters on a mountain bike. All the bits that make a difference to the performance and none of the bits that don’t. We have created what we believe is the bike that will give you the best experience of mountain biking at an accessible price point.

Calibre Bossnut specification

  • Frame // 6061 alloy, 135mm travel
  • Shock // RockShox Deluxe Select R, 210×55
  • Fork // RockShox Recon Silver RL, 140mm
  • Wheels // 30mm ID Tubeless Ready rims on Shimano TC500 hubs
  • Front Tyre // Maxxis Minion DHF EXO, 29 x 2.5in
  • Rear Tyre // Maxxis Forekaster EXO 29 x 2.4in
  • Chainset // Shimano Cues, 170mm, 32T
  • Drivetrain // Shimano Cues 10sp, 11-48T
  • Brakes // Shimano MT410, 180/180mm
  • Stem // 45mm, 31.8mm
  • Handlebars // 780 x 20mm, 31.8mm
  • Grips // Calibre Ribbed Lock-on
  • Seat Post // X-Fusion Manic, 170mm
  • Saddle // Calibre Trail
  • Weight // TBC

Geometry of our XL size

  • Head angle // 64.5°
  • Effective seat angle // 78°
  • Seat tube length // 460mm
  • Head tube length // 125mm
  • Chainstay // 445mm
  • Wheelbase // 1,277mm
  • Effective top tube // 636mm
  • BB height // 38mm BB drop
  • Reach // 500mm

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Orange Switch 6er. Stif Squatcher. Schwalbe Magic Mary Purple Addix front. Maxxis DHR II 3C MaxxTerra rear. Coil fan. Ebikes are not evil. I have been a writer for nigh on 20 years, a photographer for 25 years and a mountain biker for 30 years. I have written countless magazine and website features and route guides for the UK mountain bike press, most notably for the esteemed and highly regarded Singletrackworld. Although I am a Lancastrian, I freely admit that West Yorkshire is my favourite place to ride. Rarely a week goes by without me riding and exploring the South Pennines.

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Home Forums The Bossnut is back! Calibre’s bargain bouncer goes 29

Viewing 23 posts - 1 through 23 (of 23 total)
  • The Bossnut is back! Calibre’s bargain bouncer goes 29
  • chakaping
    Full Member

    That looks really impressive, great all-round trail bike geometry and very upgradeable.

    Is the front (where the top tube/downtube are joined) just particularly minging on the XL?

    a11y
    Full Member

    Is the front (where the top tube/downtube are joined) just particularly minging on the XL?

    That bit alone spoils the whole aesthetic of the bike for me. Otherwise, quite an appealing package. Possibly the type of thing for mini a11ys in future if I don’t go secondhand.

    chakaping
    Full Member

    It does look much less offensive in the smaller sizes.

    All of this for just £1,500? Calibre’s Bossnut is back, with more travel, bigger wheels and a higher quality frame

    Nice video and chat with the designer there too.

    2
    thisisnotaspoon
    Free Member

    Is the front (where the top tube/downtube are joined) just particularly minging on the XL?

    Presumably a necessity to get the middle of the down tube steep enough to create space to squeeze the bottle in there at the back and allow the fork to compress at the front?

    wheelsonfire1
    Full Member

    I really like the look of that, I’d heard rumours for months of a new design and I may have been tempted with it for my first full suspension but went for a fatbike. It’s the price that I think we should be expected to pay for a decent bike. Sensible. If anyone wants to lend me one to test around The Peak District, send me a message!

    kayak23
    Full Member

    That looks, well, boss.

    Great value bike. I’d be willing to look past the head/downtube interface for that.

    Always been a fan of Calibre bikes from riding their fatbike for years and years.

    MoreCashThanDash
    Full Member

    It’s got a front end only it’s mother could love, but that’s a good value offering again.

    2
    the-muffin-man
    Full Member

    I’m more shocked to see MBR is still going!! 🙂

    1
    spannermonkey
    Full Member

    Isn’t it just a rebadged Polygon Siskiu?

     

    wheelsonfire1
    Full Member

    I’ve had another look – external cable routing, Shimano parts and a strong looking front end, what I’d want if in the market. The Shimano brakes are perfectly adequate for most users too, maybe not for the Alps but ok everywhere else.

    chakaping
    Full Member

    Isn’t it just a rebadged Polygon Siskiu?

    Probably manufactured by Polygon using very similar tubes & bits, but it’s obviously built to Calibre’s spec.

    The geometry looks a bit better than most Polygons, with the 445mm chainstays for example.

    The video I linked is a good watch.

    fahzure
    Full Member

    Shame they didn’t Horst it.

    midlifecrashes
    Full Member

    Looks good. Proper thing at good price.

    Anyway if you’re about to buy one, Go Outdoors mailshot I’ve just opened has a voucher/code for an extra 20% off valid until the end of November so that bring it down from £1500 to £1200.

     

    (I’ve read the small print and can’t see any gotchas or exceptions that would apply)

    1
    Northwind
    Full Member

    spannermonkey
    Full Member

    Isn’t it just a rebadged Polygon Siskiu?

    This is all pretty tangled. At some points the Siskiu was essentially a “rebadged” Bossnut, it was developed for/with/by Calibre/Gooutdoors but made by Polygon and they had the right to sell their own. This is one of the reasons gooutdoors got so completely wrecked in the pandemic, Polygon just stopped supplying them with anything they could sell themselves, which was pretty much everything. Up til then it seemed like a pretty good mutual partnership, after that not so much! And then of course gooutdoors ended up selling siskius.

    As far as I can tell this one has specific differences and is not the same as any current Polygon, but maybe that just means they’ve got a little out of step and there’ll be a new siskiu along.

    nauticalbiker
    Full Member

    Looks good, a quality base level full suspension bike. Shame there is no UDH, this would have been in keeping with the design concept of keeping the frame upgradeable over time.

    3
    kayak23
    Full Member

    chakaping
    Full Member

    Nice video that.

    Just thought I’d add, I noticed the Calibre account teasing a higher spec version in the pipeline in the comments on the Pinkbike article about this.

    2
    Northwind
    Full Member

    Intresting that it’s a new factory, wonder if that means a complete break from Polygon?

    I think it’s pretty much a completely different development team now but it feels like the same smart ethos- my Calibre, the Dune fatbike, was a super tight budget bike and you could see they’d spent so much effort sweating the details, making the core bike as good as it could be at the price while avoiding any of the horrible standards costcuts that most cheaper bikes take, everything’s “good enough” to work out of hte box but at the same time it’s going to be reasonable to upgrade if you want as the core parts are solid. Not many £500 bikes that I’d still be riding 9 years on, sure I’ve replaced about half of it but that basically tells a story of what a good job they’d done, that it was worth doing all that.

    Also not going to lie, I still like that it’s a supermarket bike 🙂 Nice contrast to my Bird and my titanium hardtail and my ancient nichier than thou Cotic.

    didnthurt
    Full Member

    I think the design is quite well thought out. I bet the front end is pretty stiff. It has room for a water bottle with its little pop belly. The top tube is low for stand over, stiffness and less material/weight. The suspension is nice and low for weight distribution. The head angle sounds about right.

    What weight do we reckon, 17kg?

    I’d like to give one a go.

    4
    stwhannah
    Full Member

    That video reflects my IRL experiences of the crew behind the Bossnut, who I’ve had chance to hang out with a few times over the last year and a bit. Lots of actual riding and testing of prototypes and different budget components to see what actually works/is worth spending the extra on. Enthusiasm and care for what they’re creating, good riders, and stoked on riding. Feels like the kind of commitment and happy vibe you usually see with a small/passion/boutique brand, yet they happen to sit inside the JD Sports megastructure. I haven’t ridden the bike, but I like the cut of their jib!

    steamtb
    Full Member

    Looks brilliant! I loved my first gen BBB and still have my Sentry Pro; that is my wife’s now although I still ride it and it’s a superb bike by any measure, I look forward to seeing these in the flesh, I’m sure they will bring lots of smiles to the miles for many people. 🙂

    The video linked above sums it up nicely!

    6
    samjt
    Free Member

    Hey guys, Sam from Calibre here. Thanks for the kind words! Just to jump in on that headtube comment – I ride an XL and very much care about the aesthetics of the larger frames, when I saw this sample the first thing I said to Jonny is there is no way we’re letting that go to production. The XL production bikes have the angle of that downtube/headtube junction tweaked so it does look way better. I still think the extended welded section there isn’t particularly pretty and something to improve on but its definitely an improvement on this prototype 🙂

    Aaaand the never ending “Is it just a Polygon?” comment – this is why we dove so deep into the development process in the video above (https://youtu.be/dRBC0yCTX_w), it’s an all new factory, new tube set, new forgings and designed from the ground up in our little office in Sheffield. Kudos to Northwind though for the most accurate comment on this I’ve seen to date, all the Calibre bikes have been Calibre’s own designs over the years but have shared the Polygon factory hence the similarities, forgings etc. have often overlapped but geo, spec, tubes have always varied from the Polygon bikes (with the exception of the Vander models which were the bikes that the factory had produced for Calibre as Bossnuts/Sentry but sold as Polygons when they cancelled all Calibre orders during the pandemic).

    1
    wheelsonfire1
    Full Member

    Well, whilst in Go Outdoors last night I thought that I’d go and have a look at the new Bossnut. It took some finding, not displayed in a prominent location in a cycle section that was devoid of customers, and staff. It really is a quality looking bike, the deep gloss paintwork and finish are excellent. If I’d not bought my bike for this twenty year cycle I would be buying one. It demonstrates that “cheap” (a term used in different ways depending on your circumstances) doesn’t have to be poor quality, and, all the features that I would want too!

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