RockShox's new SID suspension raises the benchmark of cross-country suspension performance

RockShox SID Ultimate 24
(Image credit: GuyKesTV)

RockShox’s SID family has been some of the best XC forks and shocks for lightweight race bikes since the late 1990s. The latest SID Ultimate is our current benchmark for XC / light trail performance too, with only occasional knock and lockout reliability issues to spoil a perfect score. 

No surprise then that the new SID is specifically designed to address those issues while adding more sensitivity, more control, and more stiffness while still reducing weight. We have already had our hands on the new tech for review if you want to know how the new SID Ultimate and SIDLuxe ride then there’s a full test, but keep reading here for design and range changes.   

What no Flight Attendant?

If you came here hoping to hear that the Flight Attendant SID being ridden to record-breaking success by Nino Schurter will be in the shops soon, we're going to have to disappoint you. The Ai-actuated fork, shock, and crank sensor-based impact/pedal/angle measuring system is still very much a race development project rather than an imminent public release. That doesn't mean there isn't a lot of new stuff happening with the latest generation of the SID family.

RockShox SID Ultimate 24 lockout spool

New SIDs get a machined crown and triple mode 'Lock, Pedal, Open' low speed compression adjustment in manual or remote flavors  (Image credit: GuyKesTV)

All new SID

While new SID sticks with 35mm diameter stanchions (SID SL still uses 32mm) the upper legs are extended for more overlap and wider-spaced stanchions increase stiffness and smoothness as there’s less binding under load. That should hopefully stop bushing knock issues which we never experienced but were definitely an issue on previous generation SIDs. The new crown is stiffer too, despite being machined externally to reduce weight, netting the fork an 8g win compared to the previous SID Ultimate I tested. That makes it basically identical in weight to the latest Fox 34 SC Factory fork but 272g lighter than the Ohlins RXF34 M.2. Dropout adaptors are now included for easier fitting with conventional smaller hubs, or you can run them without to fit oversized Torque Cap hubs. 

There are big changes internally too. On the left side hollowed-out lower castings give the DebonAir+ air spring 50 percent more negative volume and 16 percent more positive volume. A coil rather than elastomer top-out spring is matched to a taller, tapered bottom-out ‘jounce’ elastomer. Both sides are lubricated with a new Maxima Plush Dynamic Suspension fluid for increased longevity and decreased friction too.

On the right side, the new Race Day 2 damper is still superlight despite a new, more robust valve head which uses a retainer O-ring as a load shim to hopefully fix previous issues where forks could lose lockout function. Like the Charger 3 damper in RockShox Lyrik and other trail forks, a lot of work has been done to reduce ‘cross talk’ where adjusting low speed compression can affect high speed compression and vice versa. 

While Fox has run three position dampers for decades, RockShox has generally stuck with a binary adjuster until now, but ‘3P’ finally adds a third ride feel option between lockout and fully open modes. According to RockShox, this was inspired by studying suspension movement on technical climbs at XCO races and realizing that the Scott athletes - including Nino Schurter - seemed to have a real advantage with the ‘Traction’ mode on their Scott Spark bikes. As a result all SID forks and shocks now have a ‘Pedal’ mode actuated via a bar remote or fork top switch depending on the model. It only increases low-speed compression though, rather than reducing travel/increasing spring progression as well like Scott’s long-running TwinLoc setup.

New SID is only available in a 44mm offset 29er option but you can choose 110 or 120mm travel settings and like the Boxxer, RockShox has tweaked the signature SID blue to create a darker ‘Blue Crush’. Pricing is slightly increased at $999 / £1069 / €1199 but that's still much cheaper than the Fox 34 SC Factory at $1,019 / £1239. 

RockShox SID SL

Longer 110mm travel and new machined crowns can be seen on the SID SL BRAIN we've been testing on Specialized's new Epic World Cup (Image credit: GuyKesTV)

SID SL gets turned up to 11 (cm)

The same Race Day 2 damper tech and ‘Pedal’ setting are added to the SID SL (SuperLight as it’s 130g lighter than SID). There’s a traditional 100mm option as well as an extended 110mm version and both get a machined crown to shave weight while increasing stiffness. They also have the new Maxima Plush Dynamic Suspension fluid inside and the same fresh ‘Blue Crush’ colorway as well as clean gloss black / pearl white. The SL is 29er/44mm offset only again, but around 10 percent cheaper than SID at $899 / £959 / €1079. 

RockShox SIDLuxe

Updated SIDLuxe Ultimate rear shock gets a reworked top end, more slam time oil flow and 12 off the shelf specific bike tunes (Image credit: GuyKesTV)

SIDLuxe shock opens up and adds ‘pedal’

Unsurprisingly RockShox has added the ‘pedal’ mode to the matching SIDLuxe rear shock too. They’ve also opened up the high-speed compression damping in ‘open’ and ‘pedal’ modes to handle bigger hits better. This is matched with a longer tapered, bottom-out bumper to control the end stroke. The shock has a new top end and 

You can now select from 12 different pre-tuned options to suit the most popular cross-country bikes, as well as standard or trunnion mount and four different remote or lever-actuated options for either the 3P or 2P damping for $439 - $509, £479 - £539, or €539 - €609. 

RockShox TwistLoc Ultimate

Updated TwistLoc Ultimate has a slimmer profile and textured or smooth grip options (Image credit: GuyKesTV)

Slimmer Twistloc

Seeing as SRAM started with Gripshift it’s maybe no surprise that they use a twist-style remote control for their suspension. The new Ultimate design is slimmed down for less interference with dropper levers though, with curved or straight cable guides and textured or smooth grip options for $117 / £119 / €133. 

Rockshox SID Ultimate

SID models from 2014 onwards can be updated with the new Race Day 2 damper  (Image credit: Guy Kesteven)

Select+ models and retrofit options

Both SID and SID SL are available in Select+ Charger Race Day two options which are essentially the same but without the machined crowns which makes them sound like a real bargain. Other versions are likely to appear on complete bikes too. The great news for anyone getting a cheaper version of the new forks or who already owns a SID is that the Charger Race Day 2 damper is available separately for $269 / £289 / €319 in 2p or 3P options and will slot into any SID model from 2014 onwards.

Guy Kesteven
Technical-Editor-at-Large

Guy Kesteven has been working on Bike Perfect since its launch in 2019. He started writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. He’s also penned a handful of bike-related books and he reviews MTBs over on YouTube.

Current rides: Cervelo ZFS-5, Specialized Chisel, custom Nicolai enduro tandem, Landescape/Swallow custom gravel tandem

Height: 180cm

Weight: 69kg