2013 Rockshox SID World Cup XX suspension fork review and actual weightFor 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…


2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.

2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.

2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.

2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.

2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.

2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.


2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.

2013 Rockshox SID World Cup XX suspension fork review and actual weight

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.


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.


  1. Is it true that the 29″ Revelation bumped down from the 20mm axle to a 15mm? If so bring on that Lyric,
    I don’t want to retro all of my wheels! What models are going to be available in 27.5″ and what will their axle sizes be? I’ve always been a RS rider, most of the time their changes make sense but the increased leg lengths and longer travel forks are begging for bigger stanchions and staying with the 110 hub spacing and larger diameter axle – it really does make a difference in the steering department! For the gram conscious SID riders and the OEM Rebas I’ll let it slide but my 120mm Reba XX and my 140mm Reba RL aren’t going to last forever and I know that I’m not alone out here.

  2. I know this is a minor thing, but I really dislike RS new graphics scheme. I’ve seen it on a number of forks across the range and I’m not a big fan. 2012’s SID with the Keronite looked nasty cool.

  3. I like the new graphics.

    I think the bigger wheels are getting 15 or 20. Haven’t seen sh#t at distributors yet, though so who knows what will be vaporware. Kill 15mm.

    I don’t think you can change the travel with a spacer anymore,,,,

  4. dumb. dumb. dumb. The best think RS had going for it was the dual air system. I could go from XC race stiff to plush with a few extra psi of air in the negative spring. Now that its not easily adjustable why bother ? RS lost my business in 2012 because they didn’t have a 120mm travel, 15mm through axle fork but I’ve missed dual air….now I have nothing to miss.

  5. I dislike the grey color. Not white, not grey, … dirty white ?
    Cradle shape is the same with other RS fork, I prefer single design for SID serie.
    1565g is pretty heavy for this category of XC fork, concurrent makes better.
    Must be try on bike to test efficiency of Solo Air.

  6. Does this, “check valve etched into the inside of the legs,” mean that you can’t buy the new damper to retro into older forks? I liked the ability to adjust the old dual-air… until I had problems with the positive chamber leaking into the neg chamber. New solo air sounds more reliable.

  7. @gatouille: 1565g seems pretty darn good for a reliable 29″ XC fork including lockout and the thru-axle. What’s coming in lighter real world including those things that is easily serviced at home? Fox can’t touch that including the lockout. DT Swiss maybe?

  8. “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 see that the Chewbacca Defense is still widely used. Gotta love Product Managers–only in their world is $1 worth $2.

  9. I wish I didn’t care about aesthetics so much but gray just looks OEM and generic… Which I guess this is. There are always options to get them custom painted with various Treks and whatnot.

  10. MBR – no, you can’t retrofit to dual air, but the “damper” cartridge in the other leg can be swapped, which is a project we have slated for this fall after the tradeshow hullabaloo dies down.

    CWS – I haven’t noticed any flexing or bending that would hurt performance for an XC racer or general trail riding, the latter being mainly what I’m doing with the bike.

  11. I am really excited about Solo Air, I wish I could retro-fit my 2012 RCT3! I can never get the negative pressure right without sucking the fork down and losing 10mm of positive travel. If it is easy to add or subtract pressure to the negative, why is it hard to do the same to SOLO Air MrXC?

  12. I have recently bought the RS Reba RL solo air 100mm.

    It’s very light and looks well built, and certainly better than my original budget Suntour fork.

    I am new to forks, but one thing, I can already tell is that is doesn’t seem to have much small bump compression, it just feels kind of dead. Very disappointing for the money I paid! I am also quite light, at around 145lbs with full kit. I think that a full coil, or air/coil combo would be better, especially for my weight range to feel plusher on loose stuff. Although, I’ve never tried a dual air, I can see how it can be tuned to get that small bump feel that people like, whereas on the solo air, it’s, sadly, not possible.

    Unless, my tuning abilities are very poor (maybe?) I don’t feel so happy with the fork. Perhaps for bigger bumps etc. its has better abilities but for my riding style its not so good. I think I should have not bought it before getting more understanding about forks! I hope it can command a reasonable price second-hand as its in nearly new condition. Ce la vie!

  13. I have the new Reba RL with 15mm ta and it’s way better than the last sus forks I had, the Marzocchi xc500 and Manitou Spyder R, but then that’s not much of a surprise.

  14. Thanks for the review, but… I’m really disappointed that you chose to compare the dual air fork using identical pressures in the two chambers; especially after telling us that you normally like to run the negative a bit higher. I used to run my dual air the same way and miss it terribly compared to the new damper.

  15. I have the 2014 Sid W/C XX 100mm/15mm, Coming from the Fox Float32 100mm/15mm, Nothing but goodthings, Nothing wrong with the fox I came from, I just wanted lighter and it was time for a rebuild..It feels great, not flexy and easy to set up, Onlything I didnt like was the Xloc system, So I opted for the fork top lock out..
    I only ride single track, very little jumps

  16. The new 2017 SIDs World Cup have also the same crown race. In the article they say that such a crown race is “for the headset race to rest on”. Does this mean that the headset’s standard crown race needs to be installed on top of the integrated crown race that the fork features?

What do you think?