ÖHLINS RXF 36 M.2 AIR FORK
& TTX2 AIR SHOCK REVIEW

Review by Cole Gregg
Photos by Cole Gregg & Trevor Lyden

Once reserved for the top tier of Motorsport suspension, Öhlins has been gradually increasing their mountain bike product range since they hit the scene back in 2012. Applying nearly 50 years of experience in performance suspension components to the mountain bike world, their TTX2 & RXF36 air combo provides all mountain and enduro riders with a highly tuneable combination that’s built to offer the ultimate in control. We put the pairing to the test on board a Norco Sight to see how they stack up in the competitive world of mountain bike suspension.

THE LAB

Öhlins RFX36 M.2 Air fork
The RXF36 M.2 Air Fork is available for both 29” and 27.5” wheels, with options from 150mm to 170mm of travel and 44mm or 51mm offset options to tune the steering feel. There is also a coil version if you are looking for the ultimate small bump sensitivity, which is offered in travel options down to 120mm for those so inclined. In the 29” version you can run up to a 29×2.8 or a 27.5+ x 3.2 tire, which gives you plenty of options when it comes to tire set up. The RFX36 makes use of a floating axle and pinch bolt setup to account for hub width tolerances and is available exclusively with a tapered steerer.

Inside the RXF 36 is a TTX18 damper cartridge pulled from their DH38 downhill fork, with a 18mm piston that’s optimized for the single crown fork. The fork has 36mm stanchions as you may have guessed and uses their 3-chamber air setup. The independent damper system uses a twin-tube design, allowing oil to flow through each tube separately to decrease the risk of cavitation and offer a wider range of damping adjustment. As far as adjustments go there are 15 clicks of Low-Speed Compression and 3 clicks of High-Speed Compression, plus an additional lockout or climb option. For rebound there are 15 clicks of Low-Speed adjustment, with a factory-set High Speed rebound. Öhlins draws upon their racing heritage by offering a settings bank developed on the racetrack, to provide riders with a good suggestion on how to get the most out of their fork damper.

The main air chamber is a self-equalizing positive and negative chamber as you’d usually see on other forks, but a third completely independent ramp up chamber is added to give further air spring control. This allows you to set sag in the main chamber and then dial in the pressure you need for that bottom out control. This acts like volume reducers offered by other brands but is much easier to adjust in the parking lot or when going from zone to zone, as well as offering a much finer tuning possibility.

The 160mm 29” model weighs in at 2,159 grams, coming in slightly heavier than the Fox 36 at 1942 grams or RockShox Lyrik at 2,040 grams. Regardless of the option selected, Öhlins approves the RFX36 M.2 for eMTB usage. Right now, the RFX36 fork will run you $1,250.00 USD/€1,189 regardless of the configuration selected.

Öhlins TTX2 Air shock
The TTX2 Air shock takes technology from the TTX22 coil version, with a twin tube damper to prevent cavitation and offer a wide range of adjustability. There are 16 clicks of Low-Speed Compression, 7 clicks of Low-Speed Rebound, 3 High-Speed Compression modes, and it is sprung by a standard 2-chamber air spring that can be equipped with volume reducers to control bottom out support. Sticking with a 2 chamber air spring allows for more air volume in both the positive and negative chambers within the confined space of a rear shock.

Öhlins have made it very easy to alter the shocks stroke if your bike can handle a bit more than the factory set up, or if you want the shock to move on to your next frame, and with a maximum air pressure of 325psi it can work with bikes with very high leverage rates.  The TTX2 weighs in at 451 grams for the 190 x 45mm, compared to say a Fox Float X2 at 664 grams for a 205x 65mm model. While the sizes are different the weight saving offered by the TTX2 is very apparent. The current price for the TTX2 Air shock is $780 USD/€915, which sits in line with other high-end offerings.

THE DIRT

Having had many suspension set ups on the Norco Sight, I was able to get a really good feel for how the RFX 36 fork changed the way the bike rode across the range of ride situations. I’ve amassed a load of seat time on this bike both before and during the Öhlins testing period, so the differences were noticeable right away. At first, I was not satisfied with the small bump performance, but the story changed once I took some time to bracket settings and find the balance of air pressure and damping. I ended up running a little more sag than other forks, while relying on the ramp-up air chamber to keep me from harsh bottom outs. The mid-stroke support provided by the RFX was quite good, if not better than the rest, which allowed me to run more sag without an overwhelming feel of the fork diving. In conjunction with the smooth compression damping, I was able to find a perfect balance of ramp up and small bump sensitivity. The HSC pretty much stayed completely open at all times – very few times did I opt for a click and never more than one. It would be interesting to experiment with the shim stack to see if there was some wiggle room to make each click a little less impactful, however this is by no means necessary to get the fork to feel great. For LSC I was generally 7-9 clicks out from closed. The change in feel for the LSC is much less profound than the HSC circuit.

The change following a more in-depth setup on the RFX36 fork really made the bike feel livelier yet retained capability at the same time. It’s responsive and supportive when pushing into the lips of steep jumps, yet very composed through rough terrain, which made me want to charge harder and harder through rough sections of trail. Finding the right set up for me did take longer than the likes of Fox’s 36, but once dialed in I felt limited need to modify the setup further. I had seen other reviews with riders complaining about a lack of small bump sensitivity, but I would suggest this is due to insufficient time focused on set up, as I really love a soft initial portion of travel and the Öhlins fork delivered this. The fork tracked especially well on off camber sections of trail that were littered with roots, perhaps thanks to a slightly more compliant chassis than the new crop of 38mm stanchion forks.

During the test period I had zero issues with the fork, with no oil leaks and all adjustments remaining in perfect working order. I performed two lower leg services at home over the long-term testing period, replacing oil and cleaning the foam rings while leaving the OEM seals in place as there was no evidence to suggest they needed to be replaced.

When it came to keeping the bike rubber side up in some hairy situations the Öhlins TTX2 air rear shock did a superb job. Just like the fork, this shock had a lively yet balanced feel. The compression circuits were very smooth when the going got rough. The LSC compression adjustment had no lack of options – while each click did not provide a huge change, there were enough turns of the dial to find a setup that felt right for the terrain and riding style in store for the day. The HSC circuit was quite the opposite, with each of the 3 clicks having a massive impact on how the bike felt. Just like with the fork I tended to keep this fully open for the most part, except for a small handful of times on sustained road climbs.

During the test I did run into an issue with the shock losing compression dampening, this was after a massive case on a large step down with an extremely hard bottom out – one of the worst I have ever had. I cannot fault the shock for this as it was 100% due to rider error and a severe impact. Would I have had that issue with another shock? I cannot say for certain, but the impact was big enough to threaten to push any shock past its limit. During the repair I updated the rebound shim stack to give me a few slower options as the OEM tune was a bit fast for my liking on big jump lines, and I was good to go again in quick time.

There was a very minimal amount of stiction throughout testing, which provided a soft and smooth initial portion of the travel. I never felt the need to change from the factory installed volume spacer options for my relatively progressive Norco Sight test base, as the ramp up was adequate for all but the hardest of hits. Even when finding the end of the travel there was a soft suggestive nudge, rather than a harsh metal-on-metal feeling. Changing settings trail side was not always the most convenient as rebound and LSC both required a 3mm hex key. While not the end of the world it is something to note. I typically ran between 7 and 9 clicks of LSC from closed, which gave me enough support without compromising the supple feel the shock provided. I did notice a change in feel with every 2 clicks so the room for adjustments offers plenty of room to play with across that 16-click range depending on your bike and riding style.

Comparing to the previously tested suspension combinations from DVO and Fox, the Öhlins TTX2 and RXF36 combination on my Norco Sight made the bike ride as if it had more travel than ever and allowed me to ignore the limits of the bike and skills. While the DVO set up I came from was very ground hugging and comfortable, whereas the Fox was more rigid and made the bike feel a little “dead”, the Öhlins set up balanced overall performance and playfulness with next to no compromises.

The Wolf’s Last Word

The Öhlins RFX36 M.2 Air fork and TTX2 Air shock combination proved to be a formidable combination when fitted to my aggressive all mountain charging Norco Sight. The twin tube dampers offered a large adjustment possibility and consistent performance for the most part, with an ill fortuned shock failure mid-way through testing that was quickly resolved. Compared with the competition, the Öhlins suspension require more effort to achieve the optimum setup, but once achieved it performed excellently, and has convinced me to spec my next bike build with Öhlins on front and rear.

Price:
RXF 36 M.2 – $1,250
TTX2 Air – $780

Website: Ohlins.com