If you’re not going for the larger 29” wheels on your trail bike it seems that the recipe of 130mm of travel and 27.5”/650B wheels can make a very sweet combination. The Bossnut’s aluminium frame has been designed around a slack 67° head angle, and has a reasonably lengthy reach, placing you in a balanced position on the bike. The wheelbase and bottom bracket heights are bang on and work well with the large volume WTB tyres that are standard spec.
With quality air-sprung suspension front and rear (RockShox Sektor fork and Monarch R shock) it’s easy to tune to get the settings right for you – plus there are rebound adjustment dials on both units and a lockout on the fork. This is an area that is often compromised on sub £1500 bikes, with cheap rear shocks and steel-legged coil sprung forks giving compromised control.
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With sorted geometry, excellent suspension and three realistic sizes, Calibre have done a great job with the frame. So, what about the Bossnut’s spec?
It’s Shimano throughout with the gearing with a full 2×10 speed Deore set-up, with a ‘Shadow Plus’ clutch rear mech. While bikes such as the Marin Hawk Hill have gone for a single ring transmission, Calibre have stuck with a double chainset and this is arguably a choice which buyers at this price would be looking for. Brakes are Shimano Deore (also a pick in the 2017 Dirt 100) and it’s good to see a 180mm rotor up front – you’ll need it on this bike.
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Wheels, just like forks and shocks, are often compromised at this price point but again it is hard to argue with what is standard spec here. Shimano Deore hubs are a solid choice and are laced to WTB tubeless ready rims. WTB also supply the rubber, with a chunky 2.3” Vigilante up front and a faster rolling Beeline out the back.
Ritchey supply the cockpit, with a 760mm wide Trail bar and a 70-80mm 4Axis stem. We’d switch to a shorter stem (if the reach allows) and maybe a wider bar too. It’s one the few areas we’d upgrade.