Jon Staples' EXT Equipped Specialized Stumpy Evo

Jon Staples' custom built Specialized Stumpjumper Evo is one classy looking weapon.

The standout feature of Jon's Stumpy for most will be the EXT suspension. Rear travel is controlled by the Storia V3 Lok damper.

The Storia is equipped with externally adjustable high and low speed compression and a single rebound damping circuit.

The adjustments are functional at each end of the dial and the shock is tuned to a specific bike's suspension design.

The gloss, raw carbon and the ti-styled colour of the rear shock look sharp together.

Jon is running a 575lb spring with one turn – 1mm – of preload.

The recent release of the EXT Era fork has taken mountain bike geeks by storm, despite the hefty price.

Jon was curious whether the claims of quality about the air spring were true. He says they are.

The air spring is comprised of a high pressure 'ramp' chamber, a lower, more regular positive chamber and a high volume negative air spring. There's also an integrated coil spring that works to give the fork a smooth break-away, similar to a coil sprung fork. Both the ramp and positive chambers are filled from the top of the fork. As with the rear shock, the fork includes externally adjustable high and low-speed compression, plus one rebound adjuster.

The 2021 Stumpjumper Evo features adjustable geometry, which is done via a type of offset plate in the headtube and a flip-chip at the rear of the chainstay.

Jon's Stumpy Evo is currently setup with the headtube set to the slack position…

...and the BB height is set to high, via the chainstay flip-chip. Jon says it's still quite low on the trail. It can be configured to run a mix-wheel as well but he hasn't gone down that path.

Maxxis tires take care of grip. His rear tire choice is the DHR II.

Jon runs the DoubleDown carcass in the rear, with the MaxxGrip compound. He may run a lighter-duty insert in the summer but doesn't like having to deal with 'full-on' inserts trailside when things go wrong.

An Assegai EXO with the MaxxTerra compound sits wrapped around his front hoop. Jon would prefer to run MaxxGrip front and rear, and an EXO+ front, but supply issues have seen him have to compromise.

Even with the DoubleDown rear tire and 28psi, Jon's been flexing those sidewalls.

Jon runs a set of Nobl TR37 carbon rims on DT Swiss 350 hubs for his wheels. He's a big fan of carbon wheels "because they stay true, almost maintenance-free."

The DT 350 hubs have been a solid, dependable setup for Jon.

He's opted to run these and not the 240 series hubs, front and rear.

From Noble: "The TR37's sine wave shape embedded into the molds, aids side stiffness." The rims feature a front and rear specific construction with a thicker bead lip and heavier rim in the rear. Internal widths vary – 31mm front and 30mm rear – with the same exterior width and profile height (20.5mm).

Being the co-founder of OneUp Components, you would expect nothing less than a smattering of their components to complete the build. Jon runs the 35mm rise OneUp Handlebar.

Initially, Jon had a 50mm OneUp Stem but has moved to the shorter, 35mm option.

Obviously, there's an EDC tool sitting in the steerer of Jon's bike.

Bar roll is set to 'neutral.'

And his brake levers are angled to a more traditional setting.

Jon has run Shimano brakes and drivetrains on his builds for years. The Stumpy Evo is no different but he does have a mix of XT and XTR. XT brakes take care of stopping duties.

203mm Shimano Ice Tech rotors front…

And rear.

A OneUp Axle-R holds the rear wheel firmly in place. The front axle is the stock one found in the EXT Era fork, at least for now.

The drivetrain is a mix of Shimano 's HG12 XT and XTR.

An XT rear derailleur takes care of shifts through the 10–51 tooth cassette.

And an XT shifter takes care of shifting.

The rear cassette is also an XT model.

But out front, Jon has opted for the Shimano XTR cranks.

The XTR cranks don't use the pinch-bolt system seen on most of the Shimano MTB range. Specialized has also been steadily moving back to threaded bottom brackets on their bikes – at least the longer travel options, including the Stumpy Evo.

The OneUp Oval Switch Ring takes care of the transmission. Jon uses a 32-tooth ring and finds the traction provided from an oval ring advantageous.

A OneUp Bash Guide takes care of chain management…

And protects the chain and ring from the many obstacles found on Jon's favourite trails in Squamish.

Jon chooses to use Shimano XTR pedals when clipped in, completing the 1-horsepower transmission.

OneUp's grip. Black to suit the rest of the build.

Mated to the Shimano XT brakes with a OneUp matchmaker is the OneUp dropper lever.

A 180mm OneUp Dropper provides enough clearance for Jon's needs.

SQLabs 611 seat in a 14cm width.

Jon runs his seat quite forward on its rails, despite the claimed 77.1-degree seat tube angle with his current settings.

RideWrapped to keep the frame in good shape, improving resale value.

Sadly, there's nothing currently inside Jon's downtube. I'm sure he'll come up with something soon but maybe readers can give him some ideas in the comments?

It looks like they've mellowed the bumps in the chainstay protector for 2021.

But there's still heaps of coverage, both on the chainstay and the seat stay.

Specialized bikes are finished to a high level and their attention to detail is excellent. This rear flap keeping debris out from between the swingarm and front triangle is a great example.

The single-sided shock mount and support makes for an interesting view when in the pain cave.

Didn't Specialized used to include a stash for a small multi-tool between the shock eyelet and the frame? It's not there now.

The stock rear shock 'link' currently holds the suspension together but Jon is considering the Cascade Components link as a future change.

That S-Works bling, nicely protected from harm behind the RideWrap.

Understated but fully loaded.