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 degree 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 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.
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.
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.