The RockShox SID SL Ultimate 2P is engineered specifically for cross-country (XC) racing, representing one of the lightest and most purpose-driven suspension forks in the brand’s portfolio. In this article, we delve deep into how it compares to competing high-performance XC forks, assessing its strengths, distinctive technologies, and fit within modern race bikes. This comparison aims to help riders make informed upgrade decisions based on performance, weight, adjustability, and compatibility.
Design and Construction Specifics
The SID SL Ultimate 2P distinguishes itself with a 32mm chassis focused on weight savings. The magnesium lower legs and carbon crown-steerer unit contribute to one of the lowest total fork weights in its class. Unlike trail-oriented forks, its narrow stanchions prioritize responsiveness and weight reduction over aggressive stiffness.
Compared to forks like the Fox 32 Step-Cast Factory or DT Swiss F 232 ONE, the SID SL Ultimate 2P is comparable in chassis dimensions but features more refined internal damping. The 2-position remote lockout lever and Charger Race Day damper create an efficient system for rapid terrain changes, offering seamless transitions between fully open and locked-out modes.
Suspension Performance and Damping
One of the SID SL Ultimate 2P’s strongest attributes is the Charger Race Day damper. It’s engineered for simplicity and performance, offering just two settings—open and locked—designed for elite XC racing. The damping performance under high-speed compression remains consistent, thanks to the precisely machined internals and high-volume negative spring.
In comparison, the Fox 32 Step-Cast offers greater adjustability, including open mode adjust, low-speed compression, and rebound tuning. While that provides versatility, it also adds complexity and weight. The SID SL Ultimate 2P, in contrast, offers fewer adjustments but a sharper execution tailored to racers who want reliability over versatility.
Remote Lockout and Ride Control
The SID SL Ultimate 2P integrates a 2P (two-position) remote lockout that connects to the left-hand shifter mount. This feature is crucial for riders looking to maximize power transfer during sprints or climbs. The remote is lightweight and ergonomic, reducing cockpit clutter.
Forks such as the DT Swiss F 232 ONE use similar remote systems but tend to require more effort in lever engagement. The RockShox setup offers a lighter actuation force and quicker engagement, giving it a clear advantage in race scenarios where timing and efficiency are vital.
Weight Comparison
The SID SL Ultimate 2P typically weighs approximately 1,326 grams (with a remote, uncut steerer). This places it at the forefront of lightweight performance forks. Here’s how it stacks up against rivals:
- Fox 32 Step-Cast Factory (100mm travel): Approx. 1,375 grams
- DT Swiss F 232 ONE: Approx. 1,480 grams
- Cannondale Lefty Ocho Carbon: Approx. 1,446 grams
Weight savings may appear marginal, but in competitive XC racing, every gram contributes to acceleration and climbing speed. The SID SL Ultimate 2P delivers elite-level performance with class-leading weight efficiency.
Chassis Stiffness and Handling Precision
Though built on a 32mm chassis, the SID SL Ultimate 2P remains torsionally stiff for XC applications. Riders report a balanced front-end feel with minimal flex, aided by Maxima Plush fluid to reduce friction and improve small-bump compliance.
Forks like the Lefty Ocho Carbon may offer slightly more lateral stiffness due to their unique single-leg design and oversized internals. However, that comes with a learning curve and proprietary hub requirements. The SID SL Ultimate 2P’s conventional design offers compatibility and ease of maintenance without sacrificing steering precision.
Installation and Compatibility
The SID SL Ultimate 2P is designed for 100mm travel applications, compatible with 29-inch wheels, and supports Boost spacing (110mm hub width). The fork fits modern XC frames without modification and integrates seamlessly with SRAM’s TwistLoc and other remote lockout systems.
It uses a tapered steerer (1.5 to 1-1/8 inch) and requires a flat mount disc brake setup with a 180mm rotor minimum without adapters. While the Fox 32 Step-Cast and DT Swiss F 232 ONE offer similar compatibility, the SID SL Ultimate 2P benefits from SRAM ecosystem integration, offering unified performance when paired with RockShox rear shocks and SRAM drivetrains.
Maintenance and Serviceability
The fork’s simplified damper architecture reduces service intervals. RockShox recommends 50-hour lower leg maintenance and 200-hour full damper service, both of which are supported by extensive aftermarket documentation and part availability.
Fox and DT Swiss forks may require slightly more frequent servicing depending on riding conditions, and their damper internals involve more complex disassembly. The SID SL Ultimate 2P is thus a more user-friendly option for privateer racers and self-maintaining cyclists.
Performance Customization Options
While the SID SL Ultimate 2P is designed with a minimalist mindset, it still allows for moderate tuning. Volume spacers can be used to adjust the spring curve, making it more progressive or linear depending on rider preference.
Fox’s Grip2 and DT Swiss’s INCONTROL dampers offer broader customization for trail-oriented riders. However, these are not always beneficial in pure XC racing, where over-tuning can be counterproductive. RockShox’s straightforward design avoids overcomplication and lets riders focus on racing rather than setup minutiae.
Pros and Cons vs. Competing Forks
Pros of the SID SL Ultimate 2P:
- Class-leading low weight
- Reliable and responsive remote lockout
- Simple, race-focused damper
- Smooth initial stroke with Maxima Plush fluid
- Wide service support and easy part access
Cons:
- Limited adjustability compared to Fox and DT Swiss
- Narrow stanchions not suitable for aggressive trail riding
- 2-position damper may limit tuning for varied terrain
Final Verdict for XC Racers
The RockShox SID SL Ultimate 2P stands out as the optimal choice for racers focused on climbing efficiency, low weight, and consistent performance. Compared to the Fox 32 Step-Cast Factory, it is lighter and simpler. Against the DT Swiss F 232 ONE, it is more efficient in remote responsiveness and better integrated into SRAM-based systems.
For riders seeking a plug-and-play race fork with minimal complexity and maximum performance, the SID SL Ultimate 2P offers the best balance of features and race readiness in its category.