For 2013, Rockshox dropped the Dual Air spring technology in favor of Solo Air systems across the board.
For the unfamiliar, Dual Air provided separate valves for the positive and negative air chambers, letting you fine tune the beginning stroke feel of the fork by putting slightly more or less pressure in the negative. Personally, I preferred running the recommended setting for my weight in the positive, then adding 5-10psi to that number in the negative. This gave their forks a very supple feel over small bumps without affecting big hit performance.
SID Product Manager Jed Douglas said the move allowed them to simplify the system by removing the second air valve and a few internal bits. A side benefit is it saves about 10g of unsprung weight. Gram savings aside, I wasn’t all that excited about losing the ability to fine tune my setup. I shared this concern with Jeremiah Boobar, one of Rockshox’s suspension engineers, and he said they took this concern into product testing but were really pleased with the outcome, saying the forks feel as good or better than before.
I received a SID XX World Cup fork for long term test, and it’s replacing a Dual Air SID XX fork on my Niner Jet 9 RDO for a straight up back to back comparison of the different air springs. So, how does Solo Air set the negative chamber? Did it perform well and make me a believer? Bounce past the break and see…
WEIGHTS & DETAILS
The only material change to the 2013 forks, in particular the SID, Reba and Revelation, is the switch to Solo Air. The damper options remain the same, and they’re outlined in detail at the bottom of this post. Alloy stanchions are 32mm and the lower casting is magnesium.
The negative air chamber is set via a check valve etched into the inside of the legs. Like a rear shock, the small valve lets air slip from the positive to the negative chamber during compression just long enough to keep both chambers’ air pressure equalized. When setting up the fork for the first time, set the air pressure, compress it hard a few times, then double check the pressure. I had to add a few psi after compressing it. Why? Because the fork has to move pretty deep into its travel for the plunger to cross over the check valve, and once you compress it some of the air from the positive goes into the (much smaller) negative chamber, and that air needs to be replaced.
For the World Cup forks, you get a full carbon crown and steerer. Compared to older full-carbon-crowned SIDs, the newer (current) versions have a metal crown race for your headset race to rest on.
The arch is sculpted and quite attractive. Sag gradients for both travel options are on the stanchions – SID 29er forks are available with 80mm or 100mm. They’re internally adjustable by adding or removing a spacer, which is a fairly straightforward operation (I’ve done it once). Mine came set at 100mm, just where I needed it.
The bottom of the fork is a bit cleaner without the negative air valve. The red rebound adjuster knob is large and easy to turn even with full finger gloves.
The fork with uncut steerer weighed in at 1,565g, which includes the X-Loc hydraulic remote lockout…which is what comes on the XX forks.
Rockshox also recently started shipping all forks and shocks with one rebuild kit included in the box, and XX models get a basic bleed kit for keeping the remote working properly. In the year & change I’ve had my SID XX I’ve never had any issues with the remote’s hose, but it’s nice that it’s included.
I set my air pressure at 120psi, the recommended setting for 180lbs. That’s my, uh, nekkid weight, but it’s where I generally set my 2012 SID. For the first ride, I put both the positive and negative air pressure at 120psi and did a lap at Country Park in Greensboro, NC, which is a fantastic XC course. I then pulled into the parking lot, swapped out forks, set the positive air at 120psi and hit the trail again. Total time between riding laps was under 20 minutes. I did this to get an honest-to-goodness back to back impressions of the Dual Air versus Solo Air.
The verdict? Both forks ended up at exactly 25% sag, which was a good start. On the trail, both forks felt remarkably similar…another nudge in the right direction. The root drop shown above comes after a nice high speed corner. If you don’t pull up, the wheels will roll off the initial logs and hit the large bottom root before cruising on. It’s a small test of a fork’s ability to take successive high speed hits. Just around the bend from this is a 40-foot stretch of rapid-succession roots on a mild climb. In otherwords, it’s a mid-speed section of constant bumps and hits, and the SID handles it well. Recovery between hits is quick without being bouncy, so it’s easy to remain in control…exactly what you want from an XC fork.
The 2013 Solo Air SID does feel slightly springier, but not in a bad way. I was half expecting the fork’s movement to feel a bit stiffer because it was fresh out of the box, but the seals and bushings didn’t seem to take any time to break in. Movement was plush on the first ride.
Oh, and the Keronite Gray looks killer on the white/black Niner. Perhaps the only initial complaint, if you look at the pic at the top of the post, is that the metal crown race spaces the fork down from the frame too much, which eliminates the flush look the alloy crown/steerer has with this and many other frames. Word is there’s a rubber spacer that’ll wrap around it to make it look more streamlined, but we haven’t seen it in person yet.
WHAT THE DIFFERENT DAMPERS DO:
Just for reference, Rockshox’s four different dampers in the SID line are:
RL and RLT are the “basic” dampers. RL refers to Rebound and Lockout, and offers a range of compression adjustment from fully open to fully locked.
The RLT adds Threshold, which adds a user-adjustable limit to the blowoff when the fork is locked out. With the RL, blowoff is set at the maximum (firmest) level, the RLT lets you set it so that it requires less force to blow through the Floodgate.
The XX damper is very similar to the RL but uses a hydraulic remote to lock it out, but it does away with the adjustment range of the compression damping. It’s either open or closed.
The RCT3 damper was introduced in 2012 and offers three compression settings: open, pedal and locked. The “pedal” setting has a
You’ll also have an range of low-speed compression adjustment in the “Open” setting. The knob looks like the Floodgate knob on the RLT, but it controls the low-speed compression only. Floodgate is like a platform, and has a low preset level in the “Pedal” setting and a higher preset level in the “Locked” setting. Internally, there’s an additional high speed compression circuit that uses shim stack, which provides an additional level of motion control for the fork. It’s preset and not user adjustable. It’s a more finely tuned feel, but it’s also the heaviest system. That said, it’s only a slight bit heavier.
These will be the same on the Revelation, all of which use the Motion Control DNA spring tube design. Reba forks use the original Motion Control. They function very similarly, but the non-DNA model is a bit heavier, and Rebas are only available in RL and RLT.