RST “First” 29 Suspension Forks: Quick Review- by Guitar Ted with Grannygear and JeffJ

Well, it has been a busy summer at Twenty Nine Inches.com, and we’ve been flogging the RST suspension forks we received a couple months back, (see Out Of The Box here) Now let’s dive in and see what kind of forks these RST “First” models are- value packed budget gems or duds….

RST First fork

Guitar Ted’s Take: My fork was the traditional quick release, 100mm travel, straight steer tube version. It installed with no issues, and with no set up guide provided, it was a bit of a hunt and peck session to dial it in at first, but this is a simple fork, so it wasn’t that big of a deal to figure it out. I weigh about 230lbs now and ended up at 110psi which was feeling spot on for how I like a fork to perform, and was within sag recommendations by most fork manufacturers. Okay, with that settled, it was off to go ride the thing.


First Impressions: My first rides were marked by an alarming squeak noise, which occurred on sharp hits. It sounded like a dog’s squeaky toy, actually! It was quite loud and so I gave it a couple rides to see if the noise would calm down. It did somewhat, but it never went away. So I contacted our RST USA man, Mike, and let him know what was going on. He figured it out right away. Some of the early production forks had a too tight clearance issue which made air escaping around the compression rod/piston assembly squeak. Mike sent out another compression assembly pronto and I was able to perform the swap easily. Probably a ten minute job from start to finish. Once the swap was made, the noise issue was completely gone. Later runs of these forks should not show up with this issue, so it was only my fork and a few others from the early production run.

RST First 29 fork
Ride Performance: The RST First series has a simple compression and rebound adjustment, much like other forks we’ve seen. I dialed in a nice rebound feel, and ran my compression knob about three to four clicks in from wide open to arrest brake dive and rider induced bobbing as best I could while riding my single speed out of the saddle. Since I had the fork apart, it was easy to see how the compression adjustment worked, it is a simple shim stack arrangement with a valve that progressively gets closed down as you dial in more compression control until you get to “lock out”, which isn’t a truly locked out setting, but rather a highly closed off valve setting on the compression rod assembly.

I really like the buttery smoothness over small to medium sized trail chatter, and all the travel was on tap without feeling like I bottomed out against something. All really good stuff here, but it isn’t all top notch. The compression settings seem to be vague, as far as feeling all that different while riding. It starts out by closing off a bit of the free movement a few clicks in, but those clicks all seem the same. It stays that way until you get a couple clicks away from “lock out. Then the feeling ramps up noticeably to become very stiff feeling. A sort of “all or nothing” feeling, it would seem. I’m wondering if an oil change might help this, and I am sure that those who know their way around a fork shim stack should have fun tinkering inside here. But that said, as stock the First fork seems a bit off on compression damping.

Conclusions: The chassis feels stiff though, I like the steering feel, and I can not detect any lateral or torsional flex. I like the fork as long as I stay seated, but once I stand, it becomes an issue with compression damping and the fork really gets activated by the rider. Not too much of a big deal on a full suspension bike, maybe, but on the single speed or geared hard tail it becomes a negative. Perhaps I need a handle bar mounted lock out, but alas- that is not an option.

Grannygear:

I have the 120mm version of this fork in a tapered HT 15QR mode.  Picking up the fork gives one insight into one of the drawbacks of a reduced cost fork…weight.  Non-tapered fork legs and heavier castings elsewhere do make for a bit of beef…5.0lbs/2268g uncut and with the 15qr axle in place.  Ooof!  Mounting the fork onto the long term Specialized Camber FS was easy enough and I compensated for the 20mm height increase by swapping stems and spacers to reduce bar height.  The Fox fork, while being a 110mm fork, still was a full 20mm shorter in the A/C height.  Out on the trail, it was a bit of a change on the Camber as it leant a slightly more trail bike feel to the ‘sort of XC-sort of AM’ feel the bike has stock.  I liked it and I don’t think it took away anything significant to the handling and was more a plus than a negative.  Setting up the initial air pressure I had no chart to go by from RST so I gambled on 90psi…seemed to have the right sag, etc, set the rebound a couple of clicks in from open and hit the trails.

rst first 29er forkrst first 29er fork

I am 190lbs geared up, and I liked the action of the fork overall, but I had a feeling I was over-pressure.  Dropping down to 80psi and then 75psi, I got into a better place in mid size bumps but the fork felt like it was packing up a bit in the slower rebound as I had less of an air spring to push back.  The fork was run all the way open in the rebound settings the rest of the test.  The compression control felt decently adjustable and I did not notice what GT did, in fact I liked it very much and found it easy to get the fork to a happy place while climbing, even out of the saddle.  It is a stiff fork and the beef in that chassis has to help somewhere…one would hope…and seat of the pants measurements tell me this fork is resolute in hard, fast corners and g-outs.

Overall, I liked the fork, but there were some parting thoughts before I handed it to JeffJ for clydesdale proofing:

  • Weight is weight and the only way I would put up with that kind of fork poundage in a 32mm stanchion tubed. 120mm, XC to moderate AM fork is if I was really pinching pennies or I was a large, powerful rider and that extra ounces were just totally offset by the bennies of the stout chassis.
  • The rebound damping is just like the older RST M29 (the ancestor of the First model)…too slow.  Even the fastest setting is not enough to keep the fork as active as I like it on the cobble-y baby heads of the dry So Cal trails.
  • The fork action, outside of the slow rebound, was very smooth and solid…not much brake dive, and it gave the Fox fork that came off there a run for its money in that regard, maybe even surpassing it in bump response.
  • Stiff, accurate steering fork.  No noodles here.

JeffJ:

We have been wanting to get a 120mm fork on the TNI Giant Anthem X 29″er test sled for a while, so when Grannygear sent me home with the RST First 29 Air, I was anxious to give it a whirl. I had a couple rides to get it set up as best I could before loading it up and heading out on vacation to the central California coastal wonderfulness near Morro Bay.

The first thing I noticed about the First Air is that chassis is pretty stout, and it does go where you point it, so I give it credit for that. The 15QR axle is pretty straight forward to set up with a grub screw that indexes the axle nut so that the quick release lever will be at the same spot when the axle is tight. I did find the dropout slots (if you could call them that) that guide the hub into place were a little too open and it was a bit of a hassle for this rider to keep the wheel in place long enough to get the axle into place. It wasn’t terrible, but I think there may be room for improvement there.

The brake installation was easy-peasy, and there is a cable housing hold down on the left lower to keep things tidy.

Try as I might, I just could not get the First Air adjusted to my satisfaction. The first issue I encountered is the range of available rebound damping was far too slow for my liking. If I had my ‘druthers, I would make the First Air’s fastest setting, the slowest setting, and it would only get faster from there.

Next was the task getting the air spring set up and the sag dialed in. I generally prefer a relatively plush, active ride that takes advantage of the most of a fork’s available travel rather than something to just take the edge off. I could not find an air pressure setting that worked for me, and I never got what I would call full travel out of this fork. It did smooth out somewhat if I ran it at over 40-45% sag, but even then it didn’t ever hit bottom. If I ran it at 25-30% sag, I found the ride to be on the harsh side and the zip tie on the stanchion indicated I was leaving a good 50mm of travel unused.

My experience with the First Air left me wondering if there were possibly some internal adjustments or modifications that could be made to accommodate my 260lbs of clyde-ness. If there is, I would be open to giving the fork another go-round as it was well made, had smooth enough travel, and resides at a decent price point. In my mind the RST First Air has potential, but wasn’t quite ready for prime time when tasked with suspending my hulking girth.

News flash!  We re-visited this issue and Clyde-tuned the fork for JeffJ.  You can do the same…read about it here!


Overall Conclusions: The First forks from RST are not going to be on the same playing field as the high dollar. refined, and highly featured forks from Fox, Rock Shox, and others of that ilk. No- this is a budget priced product and the features and overall weight of the forks reflect this. That said, we took away a couple of positives and a few negatives here.

  • The RST forks, although being a bit hefty, do have a very stiff, rigid chassis which gives them a precise feel on trail in terms of rigidity and steering feel.
  • The fit and finish are very good on these forks, and we did not note any sloppiness in the bushings, or any other signs that would give us pause, like cheaply made knobs, poor execution in the through axle, or other missed external details.
  • The forks seem over-taxed if you find yourself in the Clydesdale category. We’d like to see a fix there.  [see above note regarding tuning for big guys]
  • The forks really need to have the rebound settings to be faster. Even at the fastest settings we found them to be too slow to rebound over repeated trail chatter.
  • Compression adjustment was a mixed bag. The 120mm fork seemed okay in this regard, but the 100mm version we tested didn’t have a discernible difference from just off wide open until the adjustment was near lock out.

The RST forks have some good qualities, but more refinements are needed here to make them a player out of the box.

Note: RST has sent these forks for test/review at no charge to Twenty Nine Inches. We are not being bribed nor paid for these reviews and we will strive to give you our honest thoughts and opinions throughout.