BOS Deville AM 140 fork review

Legendary chassis shortens travel and simplifies damping controls

Our rating 
3.5 out of 5 star rating 3.5
GBP £890.00 RRP

Our review

Solid and reliable, but simplified damping adjustment blunts the performance edge
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Having a successful older sibling is always a tough act to follow, especially when the big brother in question is the amazingly competent 160mm travel Deville. This 140mm travel AM sibling is a chip off the same block in terms of the supportive air spring and chassis stiffness, but the simplified three-position damping doesn’t offer quite the same range of tuning possibility.


Tipping the scales at 1.89kg, it matches the Fox 36 on mass but doesn’t come close on all-out precision from its skinnier 34mm legs, while the 35mm RockShox Pike is lighter and marginally stiffer too. Unlike the Pike, the quick release dropout system offers compatibility between 15 and 20mm thru-axles, though wheel fitment is hampered when using the latter setup as the hub is supported only on one side, making lining up the disc and axle a bit of a faff.

We were set to be blown away by the shorter travel am fork, but unfortunately that didn’t quite happen: we were set to be blown away by the shorter travel am fork, but unfortunately that didn’t quite happen
Jungle Products

We were set to be blown away by the shorter travel AM fork, but unfortunately that didn’t quite happen

The BOS three-position compression damping lever may appear to be Fox CTD-like, but it works in an entirely different way, adjusting both high and low speed compression. Settings range from Hard to Soft and while the stiffest setting is designed for pedalling efficiency, unlike CTD the Medium setting is designed for descending, applying a moderate amount of both high and low speed compression damping; Soft is simply a ‘comfort’ setting. The latter is plush enough on the flat, but was far too divey and unwilling to re-extend on steeper sections.

In Medium, support was improved, though it created more hand fatigue than rivals on chattery surfaces, such as extended rocky sections or broken up trail centre topping. That’s a bit of a disconnect with the plain Deville, which has independently adjustable high and low speed damping, giving it the buttery smooth and traction enhancing sensitivity combined with peerless big hit support and rough stuff recovery. It feels a bit of a step backwards, even though you can adjust the AM’s Medium setting by stripping the top cap and resetting the clicker to err softer or harder.

BOS deville am 140 fork:
Joby Sessions

The simplified compression damping blunts the BOS performance edge


In terms of service and support, there have been many promises made and then broken by previous distributors, but Jungle, which has a proven track record with brands such as Santa Cruz and Niner in its stable, would seem to be the most capable yet to take on the French brand. Regardless, the fact that the Deville’s service intervals vastly outstrip its rivals should go some way to easing potential buyers. A full service is required only every two years.

Product Specifications


Name Deville AM 140 fork (15)
Brand BOS

Weight (kg) 1.89
Leg Diameter 34