New RockShox SID SL and the Legacy of the RockShox SID Fork

Key details of RockShox SID SL

• Product: RockShox SID SL
• Travel: 100mm and 110mm
• Chassis: 32mm stanchions, redesigned for bushing overlap and tyre clearance (up to 29” x 2.4”)
• Spring: DebonAir+
• Dampers:
  • Base: Rush RL
  • Select: Charger
  • Select+, Ultimate, Flight Attendant: Charger Race Day 2
• Weight: 1390g (SID SL Ultimate, 110mm, uncut steerer)
• Colour: Electric Red
• Models Available: Base, Select, Select+, Ultimate, Flight Attendant
• Wheel Size: 29” only
• Use Case: Elite-level cross country racing and technical XC trails
• Key Feature: 2 or 3-position lockout (manual or auto via Flight Attendant)
• Legacy: Evolved from 63mm original SID launched in 1998
• Positioning: Competes with Fox 34 Step-Cast and 34SL, but remains lighter and more race-focused

When RockShox introduced the RockShox SID SL (aka: Superlight Integrated Design) fork in 1998, it marked a turning point for cross-country racing. At a time when mountain biking was still evolving into sub-disciplines, the SID was purpose-built for weight-conscious cross country riders chasing every possible gram in pursuit of speed and efficiency. At 1200g – a weight modern cross country forks would be impressed by – the 63mm travel SID quickly gained a reputation for being one of the lightest suspension forks on the market, and a mainstay on elite race bikes around the world.

From the outset, the SID embodied cutting-edge design, with early models featuring the iconic blue anodised finish that became instantly recognisable on World Cup circuits. Over the years, SID forks evolved with the sport itself, evolving to a Dual Air spring system, then compression and rebound adjustment, Boost spacing, 2 and 3 position lockout and now – with the release of the new SID SL – upgrades including a DebonAir+ spring, a redesigned chassis for increasing bushing overlap, increased tyre clearance for tyres up to 29” x 2.4”and ditching the blue for the new, Electric Red colourway.

As cross country evolved to become faster and more technical, so did the SID. Travel grew from 63mm in the early days to up to 120mm with the SID Ultimate. But unlike Fox, RockShox believes that cross country forks should be capable, but not excessive. Diverging from the increased travel of the trail-ready 130mm Fox 34SL, the new RockShox SID SL is offered in 100–110mm options and weighs a feathery 1390g (SID SL Ultimate, 110mm travel, 3 position with uncut steerer).

Spied on many World Cup race bikes this season, the new SID SL features a few updates from the previous model (the Debonair+, increased bushing overlap, 29”x2.4” capacity and that zinging red colour), and is available in 29” only, with a 32mm chassis, the new SID SL range is available in SID SL Base, Select, Select+, Ultimate and Flight Attendant options. Ultimately, all models are available in 2 or 3 position (aside from Flight Attendant, whose automatic lockout feature renders manual lockout unnecessary), with the key difference being a machined, anodized crown for the SID SL Ultimate, and Charger Race Day 2 Damper on the Flight Attendant, Ultimate, Select+ models, with the Select featuring the Charger Damper and the SID SL base model with the Rush RL Damper.

Cross Country Travel: Is More Better?

In a market where brands increasingly blur the lines between trail and cross country, we are used to seeing travel increase, even on World Cup-level bikes. It’s not uncommon to see 120/120mm travel bikes getting around at pace at the highest levels in the sport.

It’s obvious that the sport has become more technical, and in turn fork manufacturers are looking to meet the technical demand of modern cross country racing in order to get their fastest ambassadors on top of the podium more often. But it comes at a cost – the 130mm Fox 34 SL pushed the limits of the definition of what cross country suspension is with its launch this year, weighing in at a shred under 1.5kg (1480g). It’s only 100g more than the SID SL Ultimate, with 20mm more travel. But in a race where marginal gains count (one cross country World Cup racer admitted to removing their crank arm-based powermeter – weighing in at 20g – for a World Championship race) is 100g too much to bear?

As you lengthen travel, the front end of cross country bikes get higher. 120–130mm cross country forks can mean that smaller riders look to find unusual solutions to bike set-up problems, as ultra-steep courses require weight on the front wheel to maintain traction. Ultimately, while you can lose a race on the descent, it’s rare that this is where it’s won. A bike set up to handle better for a smaller rider arguably offsets any benefits of extra travel for that rider.

Personally? I love a 110mm cross country fork option. For long days riding up punishing climbs, even the 10mm extra height of a 120mm fork can prove difficult to set up for efficiency. While I have loved watching the evolution of the RockShox SID SL through the years, to the point where my SID Ultimate 120mm fork has taken the model’s earlier issues with poor feel and turned it around, I have experienced difficulty in managing the front-end setup of my medium Santa Cruz Blur. 

I’m at a stalemate: if I could run a longer stem with more drop, I would be in a more optimal cross country position for the riding and racing I enjoy. Alas, with a 60mm stem, my options are limited and so are the negative rise stem options available. Is my setup mad for trail riding and shreds? Heck yeah. Is it less than optimal for toeing the line between the bunting? Also yes (and I can’t ride a small frame, for those querying bike size).

So, is this a dealbreaker or merely a small qualm in the soup of first world problems we all deal with? For me, someone who is hoping to hoon around a few club races per year, absolutely a quibble at best – 110 vs 120 vs 130mm travel is not a deal breaker in my lacklustre local loop performance. If you’re Rebecca Henderson, Mona Mitterwallner or Sina Frei, or even a state or national level racer with goals to reach, it may be somewhat more of a big deal.

Everything in life is a tradeoff, and nothing illustrates that more than the demands of World Cup cross country racing. If we were racing to just win on the descents, we would see a range of Maxxis DHF/DHR tyre combinations. But cross country is as much about the climbs, so we don’t see chunky enduro tyres on cross country race bikes – is it so different with suspension?

One thing is for sure, the RockShox SID SL has become synonymous with performance in the cross-country space. For over 25 years, it has helped define the genre, remaining at the sharp end of racing and riding through decades of innovation. Let’s hope that never changes!