Fox has released its new 34SL cross-country mountain bike fork, with the brand betting big on bumps in XC travel by offering a 130mm variant and increasing air-spring volume.
Unlike the 34SC it replaces, the new 34SL uses a full-width 34 chassis for increased stiffness, which Fox says has resulted in a minimal weight increase over the Step-Cast variant. The new fork is only 3.2 per cent heavier at 1,475g compared to 1,422g, according to Fox.
The new fork looks to be shaped for the ever-increasing technical requirements of World Cup XC racing, with courses now including features that wouldn’t be out of place in a bike park.
With the next generation of cross-country bikes expected to spec the new 34SL fork, it seems likely that we’ll see a general boost in travel across brands.
Whether 130mm rear-suspension travel will follow is unknown, although many bikes, including Specialized’s Epic World Cup, use a mixed-travel setup.
For riders looking to stay in more traditional travel ranges, the new fork also comes in 110mm and 120mm variants.
The new fork is priced at £1,259 / $1,099 / €1,469 / AU$1,899 for the Factory 34SL, £1,119 for the Performance Elite 34SL and £749 / $649 / €869 / AU$1,149 for the Performance.
Ai arch
The new Fox 34SL uses an optimised generatively designed fork arch that wraps around the lower legs to increase torsional stiffness.
Cut-outs have been made in strategic places to minimise weight.
We’ve seen this on the 32SC released last year, although this time Fox has placed the arch on the front of the fork.
Unlike the 32SC, the new fork uses a generatively designed crown made from 7000 series aluminium with larger internal lightning bores and a black anodised finish.
In a win for mechanics worldwide, the damper can now be removed using a Shimano cassette tool.
The crown looks similar to the skeletal design seen on the RockShox SID Ultimate.
Combined with the full-width chassis and a Kabolt axle, the 34SL is said to be 17 per cent stiffer than the 34SC.
With the chassis being wider, the new fork also has room for 2.5in tyres.
We’ve seen a trend in riders picking wider tyres on the World Cup circuit, with many racers deciding better grip and higher volume is a worthwhile trade-off compared to the minimal increase in rolling resistance.
There is also room for 203mm rotors, which wasn’t possible on the Step-Cast design.
Better bushing overlap
The new 34SL sees an increased bushing overlap of 20mm, which Fox says has made the fork much more supple.
Bushings sit between the interface of the lower legs and stanchions of the fork, with most mountain bike forks featuring two on each leg.
The distance between the upper and lower bushings is called the ‘overlap’.
When a side load is applied to the fork, the bending force is translated from the lower leg to the stanchion via the bushing.
Increasing the overlap reduces friction, leading to a smoother compression throughout the stroke.
Fox says riders should notice increased suppleness at higher speeds when the bending forces are greater.
GRIP SL damper
Fox’s GRIP SL damper features inside the fork, with the short-travel specific damper reducing weight, while still being up to the task of World Cup XCO and XCM races.
The brand says the damper has optimised pedal-to-bump efficiency, while remaining one of the lightest on the market.
Inboard bypass channels
The fork features a new architecture that sees the bypass channels run on the inside of the legs.
Bypass channels reduce pressure ramping for increased small-bump sensitivity, while recirculating bath oil to lubricate the bushings and seals.
Fox says relocating the bypass channels to the inboard side reduces the dynamic friction by keeping them away from the fore-aft load path through the fork’s travel.
Weight savings
Fox has shaved grams in many areas to get the full-width chassis down to a competitive weight, with the Factory and Performance series forks both using the Kabolt SL axle, which saves 12g over the standard Kabolt axle.
The brand has also used double-butted stanchion tubes on the damper side, saving another 9g.
Twin Stick Lever
Alongside the new 34SL, Fox has released an updated bar-mounted lockout lever.
The new Twin Stick Lever combines a cable dropper post actuation and cable suspension lockout into the design – similar to Scott’s TwinLoc and Orbea’s Squidlock systems.
The lever uses ramps and catches to operate smoothly, with Fox saying very little lever force is required to operate both functions.
Twin Stick is compatible with both two- and three-position suspension-lockout systems and can be set up for fork-only should you be a hardtail hero.
The lever weighs 66g, or 76g with the clamp.
Fox says this helps to make its Super Light XC ecosystem the lightest on the market.
The Twin Stick Lever is priced at £184.95 / $149 / €199.
