The First SID - 1998Today saw RockShox release two all-new SID forks
(and a shock), but the 'Superlight Integrated Design' acronym has been around since 1998 when the original version debuted with puny 28mm stanchion tubes and just 60mm of travel. These were very different times than today, and riders didn't expect much from their cross-country race bikes besides quick handling and, of vital importance, absolute minimum weight.
Front suspension was a proven advantage by this time - the BoXXer was released the same year - but that didn't mean that racers were okay with adding any more grams than necessary. Good thing the SID had a hollow crown and proprietary internals that added up to just 2.6lb (1,200-grams), or about 0.4lb less than the sturdier Judy SL. While the Judy was an all-around fork that employed an elastomer and coil-spring combo, the SID was air-sprung because grams, and it even came with drilled-out titanium foot bolts and titanium V-brake bosses. In fact, the 2021 SID SL Ultimate weighs around 130-grams more than that first SID from over two decades ago, although I suspect they perform very differently...
This was twenty-two years ago and things were, well, let's call them less refined; you used a needle valve to inflate the fork, meaning you could fill up your football and your SID at the same time. Damping? It had the newer C3 cartridge that was said to be much more reliable than those older, plastic-walled dampers used inside early Judy forks. Adjustments were minimal, with a single dial that hopefully controlled rebound damping and no lockout function.
That first SID sold for $700 USD back in 1998, or around $1,100 in today's money.
The Dual Crown SID - 1999
The SID family tripled the following year, with the SL, XC, and the dual crown XL models showing up in 1999. The latter has to be one of the oddest forks that RockShox has ever offered.
Mountain biking was figuring itself out at the turn of the decade, and there was still room for ideas that seem nothing but strange in 2020. That included a dual crown SID with either 80 or 100mm of travel that was, aside from the longer Easton tapered stanchions, an additional upper crown, and slightly different lowers, pretty similar to its one-crown brothers. RockShox made a (relative) jump forward in both damping and spring departments, too; separately adjustable positive and negative air chambers filled the left leg, while a two-way adjustable damper had dials that controlled rebound and compression.
RockShox offered SID upgrade kits so riders could bump up in travel from 80mm to 100mm if you bought the former and wanted more squish. Also available for aftermarket purchase: accordion-style fork boots.
The longer upper tubes and second crown didn't mean that the SID XL was intended for serious downhill use, though, especially given its quick-release dropouts and a hardly believable weight of just 3lb 14oz.
The Carbon Fiber SID - 2002
While the newest SID ditches the one-piece carbon fiber crown and steerer unit in favor of an aluminum version that's said to be even lighter, minds were blown eighteen years ago when RockShox introduced their SID Race Carbon.
The 2.6lb (1,200-gram) fork came with the coveted BlackBox label, a reference to RockShox's top-tier support program that supplied gear to their fastest riders racers, but it didn't get the troublesome gold clout-coating on its stanchion tubes that the Titanium Race version received. That's probably a good thing - that gold coating would flake off if you even looked at it the wrong way.
Photo: PB user pawellibicki
While carbon is used almost everywhere these days, RockShox is still the only brand to offer a telescoping suspension fork with a carbon fiber crown and steerer, and that was back in 2002 when the expensive black stuff was far less ubiquitous than it is these days.
The Swole SID - 2009
2009 was a big year for SID, literally, with RockShox upsizing its chassis from using those now comical looking 28mm diameter stanchions to the 32mm tubes and wider stance we're used to seeing today. This required new magnesium lowers, of course, which were also substantially beefier than the previous version. This was done partly due to 29ers requiring beefier components, but also because more and more was being expected of so-called cross-country bikes as riders weren't just using them between the tape on Sunday morning.
The result was a dramatic - and much needed - improvement in steering precision that was, according to reviews at the time, well worth the slight increase in weight compared to its flexy predecessor.
Photo: PB user pawellibicki