RockShox RS-1 Full Fork

With RockShox set on dragging this one out as long as possible, they have finally released a full shot of the fork. While there are still rumors of a fatbike fork, we’re pretty sure this isn’t it. Instead, the inverted single crown fork with “predictive steering” looks to be a contender for a new ultra lightweight cross country fork, likely with around 100mm of travel. We’re assuming that since it is pictured with a hub that it might use a proprietary hub and axle with rumors of 15×110 being tossed around. Obviously it’s all speculation for now, but we should have the full details soon!


  1. Time will tell if this attempt is successful, but others have tried and failed.
    In fact, inverted forks have had very little success in MTB. Even in DH manufacturers who tried, ended going back to the traditional design.
    SRAM is a big fish,however, and if they put all their marketing effort in making it succed, they’ll get it.

  2. If you look closely, you can see how the crown is really low. That will help 29ers get a lower front height, finally. Considering all new forks in 29er need a thicker axle, I think this makes sense. Also I bet they went for a 20mm axle, as that will be the only link between the two legs. I wonder if it will have a remote, or maybe it’s electronic? Also, I bet the body and steerer tube is all made of carbonfiber… not sure of that, carbon heat disipation is very bad, but still.

    With this system stancious are always lubed, and wiper lips and the foam that stops the oil from scaping and all that stuff. Racing mortorbike have used inverted forks many many years ago, same in motocross, right?

  3. @Ady The brake mount [post] can be seen sticking out from behind the left fork leg.

    The Predictive Steering technology represents a game-changing development in the world of bicycle directional accuracy. With current [dare we say “primitive”?] standard steering mechanisms, the user can choose the direction of travel with no infallible, 100% guaranteed method to assure that the vehicle will move in the desired vector. Predictive Steering is a new paradigm that will take mountain bikers, and perhaps all of humanity, in a new direction, toward a better tomorrow.

  4. The thing is, though, new technology can make old designs compelling. We will see many approaches come, go, and come back again–each approach falling in-and-out of favor by an advancement in this technology or that technology.

  5. Those look like cable guides on the left leg, and the mount sits behind it at an angle. I’m not sure what flexing over such a tight radius will do to a cable, or what having a mount that sits so far out will do to rigidity.

  6. @Pasabaporaquí. i agree.

    i’m not in the xc market, but my two cents- that thing looks terrible and cheap all at the same time. sorry rock shox

    as far as a lefty “that’s a league on its own…” here is my take:

    a lefty suspension fork is like a one legged man in a butt kicking contest,
    i would not bet on either.

  7. K11- Obviously you have never used a Lefty, Therefore you cannot be trusted to know anything about bikes. Guess you dont fly much either, almost all landing gear are Lefty’s, but if you would not bet on it you would not fly.

    Lefty – Lighter, Stronger and Stiffer, nothing compares.

  8. Hey all….K11 knows what he’s talking about. He’s a huge name in suspension design and one of the leading names in composite technology. We really all need to listen to him. He’s the man to follow on these threads, on Pinkbike, and MTBR. MIT genius type.

    Whoops, sorry. That’s K12 I’m thinking of. My bad. Ignore the above comment.

  9. And a tapered steerer…. I still like my steel Xcode from the 90’s rocky altitude full xtr v brakes prestige ultralight tubing…. It’s all I need

  10. if there’s needle bearings in your fork, I feel bad if you think that’s what a good piece of suspension can feel like. lefty = boo

  11. if it’s not a 15mm through axle, count me out. not changing out the 3 sets of wheels I’ve built up over the past few years…

  12. Not necessarily new technology. It’s been 20 years since the Halson Inversion fork first appeared so the patent is up. There are probably key BASIC technologies that are up for grabs now that make an inverted fork practical without having to pay a royalty fee.

    We can probably expect other companies to jump into the inverted shock market. Wait until the Headshox patent is up.

  13. Finally. The last single crown inverted fork was made by Maverick, I believe. Before that, Marzocchi. They made the Shiver inverted single crown fork about 10 years ago, or more, maybe 15. Supposedly, neither were any good, but if someone actually threw some real money at developing one of these, it should work. Way less unsprung weight, seals are less sticky. There’s gotta be a reason every performance motorcycle on and off-road, uses this design. I’ll be this will be the standard for all MTB disciplines in 5 years. With dual crowns, there’s no reason why not. They’re stiffer and lighter. I’d love to see Fox’s answer to this.

  14. I was laughing at reading what MaLóL wrote. Heat problem??? LOL !!
    Motocross bikes forks when used by a top riders only gets to about 60c degrees. So I do not think MTB riders will have any problems with carbon heat dissipation.

    I had Maverick forks about 8 years ago. They worked good but the oil seals were crap. And you had to have a good understanding to set them up correctly for your weight and riding style. But when they were sorted , it was good.

  15. @ anyone who invokes motocross forks: those have two crowns, and this has one. That’s a huge difference.
    Most designers who make USD forks, heck, sometimes even dual-crown USD forks, end up doing extra stuff to shore up torsional rigidity. Maverick- upper legs bulge out to the size of baseball bats; huge 24mm axle; upper crown is welded to legs. For the carbon version of the fork which didn’t make it to market before Maverick folded- they made the upper legs still larger. Forget who it was- keyed, dropper post style interface between inner and outer legs to prevent twisting. Halson Designs- huge (for the time) hyper-rigid tubular fork brace. Manitou- hex-shaped thru-axle to prevent twisting. DVO- colleted fastening between crown and legs (this feature was abandoned because it was too expensive), leg guards which double as an actual fork brace (albeit a long and flexy one). And of course Cannondale- square legs, needle bearings instead of bushings; integrated leg-axle.
    Long story short- a lot of these features could be used (and have been used) even on normal forks. USD forks, unless they have two crowns, are gimmicky and greatly benefit from weird design features to up stiffness. Because otherwise, single crown USD forks don’t cut it.
    Wonder what RS is going to do make this design sort of work.

  16. On the Pic seen on drunkcyclist’ facebookpage, it looks like there is a cable (remote lockout?) exiting from the top left part of the crown!

  17. @deboat

    If you ever read anything about dt swiss froks and previously USE forks, you will know that it was quite an issue indeed. Motocross forks have lik half a liter oil, sweetheart, and bigger everything, and are not made of carbon fiber… it’s not the inverted design the issue with heat disipation, is carbon fiber. As far as I know it would be very stupid to use a carbon fiber heat dissipator, they are all aluminium or copper.

    do your homeworks next time.

  18. @Tim

    You are 100% right. but still, this is for XC, the axle may be 20 or larger, it must be about 100mm travel only… but again, if fox uses other system, and manitou dorado and single crown inverted fork failed, this one may fail too. BUT if you look at flimsy dt swiss 28mm forks, how light they are and still used at XCO world cup, it htink there is a small chance this rock shox design is good.

  19. Lefty’s are good when new, after 500km they start sucking big time. They are sh!t for enduro use and removing the front wheel is a big mess. they are expensive and mainteinance is also expensive and 10 times more frequent than fox or rockshox. (deleted)

  20. I’m not a big Rock Shox fan and of course the proof is in the (long-term) riding, but I do like what I’m seeing.

  21. @Melol – That’s all bollocks about lefties, isn’t it?

    DOI – I’ve got about 2000 miles on mine with no probs; removing the front wheel isn’t that much of an issue (though clearly it does require undoing a whole three bolts), and the oil change interval is 3x that of Fox forks. But yes, they are expensive.

  22. @MaLóL

    On a traditional fork you need to remove the front wheel to change a tube or tyre. You can leave the Lefty on for that.

    FYI I’ve got around 1000km on my Lefty and zero issues so far.

    To everyone else talking smack about Lefty’s. Just try using one for a day.

  23. heat dissipation: 100mm travel, damper may possibly be located in the lower. then the exterior wall is aluminum. still, not much of an issue for xc use. downhill and similar, i’d be concerned, but not for xc. for example, most cartridge style dampers in forks leave an air gap between fork leg and cartridge, practically insulating it. manitou used a micro sized damper in their r7 (or whatever it was called in 2008) to save weight.
    the key will be how they address directional control concerns, be it with keyways in the lowers or axle or something else entirely.

  24. Brattercakes – if you know your RockShox history, RS-1 is actually a very cool name. Or at least one that carries a lot of expectation and pressure to be industry-changing. RockShox has been pumping out some great stuff for the past few years – I’ve no doubt that this fork will perform adequately. Now….living up to the hype or it’s name? Who knows.

  25. USD mountain bike forks have always had one issue…scale. Motocross forks use a much larger axle and stanchion diameter that can overcome the torsional twisting forces. Its the only reason other designs have not done so well. Its the reason Maverick tried with a 30mm axle and the lefty uses their problematic (bearing migration) needle bearing interface. With all the R&D that has gone into telescopic seat posts and keeping them correctly orientated my bet is that SRAM has learned a thing or two about key way design in the process. Looking forward to seeing how this goes.

  26. Looks like fork isn’t just for pure light weight XC since the pics appear to be on a Camber so should be 110mm travel for that frame.

  27. @doubters It’s all just a matter of money and time spend on development. Bigger fork tubes, carbon fiber, bigger axles, they’ll figure it out. Every time new tech like this gets introduced to the mtb community, there’s always people saying it’ll never work. There was the same kind of resistance to rear suspension, hydraulic disc brakes (huge resistance, in fact), carbon fiber frames (or carbon rims). If we listened to the doubters we’d all be riding hardtails with elsastomer forks (because moto technology doesn’t apply to bikes, lol) with rim brakes. There’s a reason why the inverted fork keeps coming back. It’s simply a superior design. Like I said, just a matter of time.

  28. @ andy @ felix

    1000Km on a lefty, wow!!! that’s a huge amount of km’s!!!!! congrats!! My current SID has 10.000Km’s My SID from 1999 went ten years and 50.000Km’s with no mainteinance… no lefty can say that.

    Nowadays flats do not exist with latex. But to put the bike in a car, to remove front wheel in a lefty you have to remove the front brake caliper, and then install it again and center it again. So easy and fast… that fork eats the needle bearings and it steers better to the right than to the left when it’s needing service. But still, it’s a great living room fork, for people who calim it’s going well after 1000Km’s


    I still think this RS-1 may work. I won’t be buying it before 2020. You can be the guinea pigs.

  29. User experience with leftys can’t stand up to Malol’s experience. No way. Just ask him. Just ask all the suspension companies he consults with. He’s a big name. ask him.

    to me the real life pictures of the RS-1 look like a bit more travel than 100 or 110
    1. they wont waste clearance height … and tire to crown looks wiiide
    2. comparing the upper half of the brakerotor(180mm?) to the possible stroke…
    3. hans dampf tires aren´t that common choice for XC

    …or perhaps the 1 in RS-1 tells us “One fork for every wheelsize”
    and you could internaly put some spacers in for 29er or 27,5er clearance by remainig travel

  31. I’d just give it a go. RS has been on a roll lately. A good roll at that. If the dampers are dialed they have a great head start to address the other design concerns. Nbfd, people.

  32. @what and sevo. i have ridden the 26 and 29 lefty versions. one was a rental bike when i flew (yes on a plane) on a ride vacation. The place just had a fleet of cannondales in the rental. i know people that i ride with sometimes that feel the same way you do, in love. but my take AFTER riding is, just not a fan. so sorry i struck a nerve with y’all, but i feel i am entitled to my honest opinion from my experiences using said product.

  33. @K11- people would criticize your opinion less if you justified it right away with experience and specific reasons. You do have experience with it, but never said why you didn’t like it beyond “JUST not a fan” (emphasis mine). Now if multiple come along complaining about high maintenance, poor damper function, etc., then there is a case.
    Sometimes, of course, a product does kinda suck, but the people who spent so much money on it can’t admit it. Example: Chris King rear hubs (I have never seen one that didn’t come slightly, still rideably loose).
    I have no dog in the Lefty fight- you just explain yourself poorly.

  34. This ^: “Sometimes, of course, a product does kinda suck, but the people who spent so much money on it can’t admit it.”

    Spot on. And is the sole reason many products have hung around as long as they have.

  35. @Tim. you are right. i do not give specifics sometimes, and your comment is constructive and i will try to avoid some of my vague comments. i have fallen into the rude comment group of people on BR. need to change this moving forward.

  36. @K11- There are few things I enjoy more than a rational discussion about biking and bike parts. Looking forward to reading your comments, have a good ride!

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