Bicycle Design

SR Suntour Swing Shock

Suspension for the road is not exactly a new idea. Many of you probably remember the Paris-Roubaix SL fork that Rock Shox introduced in the early 90’s. Prior to the Roubaix fork, a hundred or so years prior to be specific, there were many other ideas floating around for suspension systems to take the edge off of rough roads. It is an old idea, but I think the Swing Shock that SR Suntour launched at Eurobike  brings something new to the table. The Alloy and Magnesium Swing Shock was designed to replace the rigid forks found on many urban and commuter bikes. It offers 30mm of travel at a reasonable weight of 1300g (2.87 lbs), and it has simple lines that visually work on an urban fixie or singlespeed.

Those urban cyclists, who gravitate toward a clean aesthetic, are exactly the types of riders that the design team set out to win over with this fork. According to a spokesman at the company:

“They had to create a suspension fork, which would convince the rigid fork fans with a sleek and slim design coupled with suspension comfort. The 30 mm of travel absorbs the main hits from cobblestones, sidewalk curbs, little stairs and potholes. The rigid construction allows better acceleration whilst pedaling and the fork weight of around 1300 g is 400g under the lightest standard suspension fork. The low built-in-height allows rigid fork replacement without changing the original bike geometry.”

You can find more information about the Swing Shock on SR Suntour’s website. Also, be sure to check out their video on Youtube. I do think it provides a nice option for suspension on a clean urban bike…and I especially like the integrated fender idea. I guess time will tell if the fixie kids agree with me.



Posted

in

,

by

James

Tags:

, , , , ,

Comments

43 responses to “SR Suntour Swing Shock”

  1. Tweets that mention SR Suntour Swing Shock | Bicycle Design — Topsy.com

    […] This post was mentioned on Twitter by James@BicycleDesign, Wally Alief and Koobi Bike Saddles, Cycle Blogs. Cycle Blogs said: Bicycle Design: SR Suntour Swing Shock: Suspension for the road is not exactly a new idea. Many of you pro… http://bit.ly/bWVsws […]

    Reply
  2. Will Avatar
    Will

    1700g would be considered heavy for a XC fork, one with 100 mm of travel, one I would consider of “standard” design from Fox or RockShoxs.

    Reply
    1. James T Avatar
      James T

      This fork weighs 1300 grams, not 1700. The very lightest and most expensive XC forks are roughly in that same weight range (I think the newest SID XX World Cups come in just under 1400 grams). Keep in mind that those top of the line XC suspension forks cost well over $1000 and are designed for racing, not commuting. For a simple, reliable coil spring design at a much lower price point, I think 1300 grams is pretty light.

      Reply
    2. Logan Avatar
      Logan

      Even 1700g is quite light for XC suspension forks. In the context of commuter forks, I’m sure they are comparing it to options like RST and others that aren’t nearly as well designed or attractive. This design looks like it would also provide easy tuning for ride stiffness or rider weight with easily swapped coil springs, and eliminate the stiction issues that plague short-travel forks. I only worry that the pivot point may allow flex that would translate to bad steering feel?

      Reply
  3. andy Avatar
    andy

    This is actually pretty good. It’s a much cleaner look, and offers enough suspension to help round out little bumps in the road. Well designed.

    Reply
  4. Clancy Avatar
    Clancy

    New take on an old design. Shelby Bicycles had a fork called “Shock Ease” that worked much the same back in the late 1940’s. To absorb impact, the lower portion of fork moves forward. This action compresses the hidden spring, which returns the fork to its original position.

    Reply
  5. Ross Nicholson Avatar
    Ross Nicholson

    Any idea of its cost?
    The most beautiful of designs is worthless if it must be made of “unobtainium”.

    Reply
    1. James T Avatar
      James T

      I haven’t seen an official retail price, but if this is an accurate indication, the price is well under $200.

      Reply
  6. Gillis Avatar
    Gillis

    Imo, suspension on a commuter is just unnecessary weight. For all but the worst roads, a quality steel fork and large diameter tire is plenty “suspension”.

    I’d also mention that this design becomes locked out under braking. The travel arc of the wheel is up and forward due to the pivot location. The braking force will pull the wheel down and back, more or less.

    Reply
    1. andy Avatar
      andy

      It could allow a commuter to use narrow and faster tires though, instead of relying on large heavy tires as the suspension.

      Reply
      1. Gillis Avatar
        Gillis

        Perhaps, but narrower does not mean faster. The fact that pro’s are using larger diameter tires now proves that at least to some degree. Besides, you’re commuting, not racing.

        Reply
        1. andy Avatar
          andy

          The pros will use whatever their sponsors pay them to use. Besides, a “wide” racing tire is 25mm instead of 23mm, so it’s not really a big difference there. To use 23-32mm tires instead of 45-60 that many commuters use would be significantly faster. I commute on 28/28 most of the time, 28/32 in the fall and winter. There’s no way I would ever pick a wider tire without expecting to go slower. And even though it’s commuting and not racing, there’s zero point to riding with more rolling resistance if it doesn’t offer a benefit. If you already have a shock (possibly like the one mentioned) than wide tires are less necessary. Who wants a commute that takes longer?

          Reply
          1. Gillis Avatar
            Gillis

            The benefits of larger tires is well known: more stability, better traction on rough or wet roads, better protection against pinch flats, better when encountering occasional debris (gravel, glass, etc) in the road. Suspension doesn’t cover all that. I’d rather change fewer flats and stay upright in the long run. There are plenty of lighter weight, large diameter commuter tires out there too.

            And I for one welcome a longer commute when I can make it so (usually on the way home 🙂

            Reply
          2. kaszi Avatar
            kaszi

            Commuters are not pros.
            I am happy with my 2lbs each 622×37 Marathon Plus tires, my bike weighs ~45lbs when going to work. I can still keep my speed at 17-19mph on average, had no punctures for the last 3 years and have a blast any time I find a stretch of trail with hardpack.
            Funniest thing is that most of the time I can keep up with people doing group rides in the morning.

            Reply
    2. Tim Avatar
      Tim

      I’ve been riding on a swing shock for a while now and can assure you that this is not the case, the breaking force against the fork is counteracted by the riders weight transfer pushing down / forward on the fork and the result is no fork dive and better control under braking. I would recommend them to anyone, they work exactly how you think they should.

      Reply
  7. dwainedibbly Avatar
    dwainedibbly

    Disc brake only? And how do I mount a fender? Calling this a fork for an “urban bike” is silly.

    Reply
    1. James T Avatar
      James T

      No, not disk brake only. They offer one with bosses for V-brakes or cantis as well. As for the fender concern, look at the picture from Eurobike that I linked to in the post

      Reply
  8. pierre FABRE Avatar
    pierre FABRE

    That YouTube video dissapointed me: it show nice images but it doesn’t show at all how the shock absorber works on rough surfaces. When pedaling in the street you can see the rider stil avoids the cobbles areas next to him. A beautiful item for sure, but no proof of its effectivemness. Is this only a piece of bike fashion?

    Reply
  9. mommus Avatar
    mommus

    i really like the way they’ve managed to fit the spring/damper into a standard head tube… which is guess is what contributes to the clean look. Although as some have already mentioned here, the flex/dive under braking would require closer examination.

    If it’s really as cheap as you say it is then I could see it being quite popular.

    Reply
  10. Nick Hamilton Avatar
    Nick Hamilton

    Does the suspension action work in the wrong way? If you hit say a curb wouldnt the forces act in an opposing way? The forks want to move forward to absorb (also slackening the head angle) where as the impulse is moving them backwards?

    The idea of a rubber rebound damper sounds a bit off, ie not a lot of dampening

    Reply
  11. lolmaus Avatar
    lolmaus

    Hehey! They’ve reinvented the springer fork! 😀

    Reply
    1. jorgensen Avatar
      jorgensen

      That was my thought almost, not quite the same geometry, but close enough for me to stay away. Long long ago riding a friend’s Schwinn Krate bike with the springer fork and drum front brake, I tested braking while under fast sweeping turn. I recovered from he abrasions. Braking is going to do Bad stuff to the geometry of the fork and the wheelbase, and tire contact patch. Interesting, but dangerous.

      Reply
  12. Morpheous Avatar
    Morpheous

    Why is it that Cannondale’s designs are ignored over and over?, the Silk Road Headshock accomplished this feat with even better damped movement, lighter weight, and normal aesthetics years ago? This design has exposed hinges, is not natural looking and just bounces along on a spring. We all lost whe Cdale tanked. They were years ahead.

    Reply
    1. Gillis Avatar
      Gillis

      Cannondale is still around. And they do offer one urban/commuter bike with a headshok. But the Headshok, while it works very well, is very difficult to maintain. It shouldn’t need much maintenance ever, but when it does it will be expensive.

      Reply
  13. Mommus Avatar
    Mommus

    Let’s not forget that the cannondale headshock requires a quite specific frame. Specifically one with a large distance between the bottom if the head tube and the top of the wheel. This design seems to work with a regular frame

    Reply
  14. COOL FORKS « FIXIE GC – fixed gear gold coast

    […] cool concept, would look decent on a single speed set up . more here […]

    Reply
  15. BikeAmateur Avatar
    BikeAmateur

    To tell the truth, I like the way it looks like very much. I highly appreciate the design. Plus such suspension would definitely help on bumpy roads. Very nice

    Reply
  16. Ken Avatar
    Ken

    Wheel swings (through travel arc) forward into bump(s) which will likely chatter, work against braking force and increase rake. I suspect the fork will be sketchy.

    Reply
  17. DF Avatar
    DF

    This was done 15 years ago. Back then it was called the AMP fork and it didn’t survive. Almost no travel when you hit a bump but massive brake dive when you so much as touch the brakes.

    Reply
    1. James T Avatar
      James T

      The old AMP linkage forks may not have survived, but I don’t think they were nearly as bad as you describe. Don’t you remember other forks from that era? Certainly Horst Leitner knew a thing or two about suspension. Without his innovative AMP Research designs, full suspension mtb technology would not be where it is today.

      Reply
    2. DaveW Avatar
      DaveW

      You’re thinking of the old 1st gen AMP forks that had a falling rate linkage and, though they had lots of room for improvement, were a pioneering effort in the new field of MTB suspension, also, it was a 4 bar linkage not a single pivot like this one. AMP gen 4 forks still fetch crazy money even though they’ve been discontinued for a decade. As James T rightly points out, the AMP main man also developed the FSR link which is the only truly efficient MTB rear suspension design ever made. I would argue that the AMP F4-BLT carbon is still the best XC racing fork ever made too. This SR fork is just right for what it is designed for, commuting.

      Reply
  18. Anon Avatar
    Anon

    It isn’t just suspension that isn’t new. This exact swinging fork design with the shock hidden discreetly in the steerer can be found on bikes at least 100 years ago, such as in the 1904 Columbia (American made) Model 138 to compensate for the harsh ride of solid rubber tires.

    Reply
  19. Daz Avatar
    Daz

    Has anyone actually ridden on these forks yet? They are cheap to come by and light in comparison to any shock absorbing fork.
    Also they look perfect for hybrid use, alas the heavier bike may not react as well but design wise better than carrying around heavy forks surely?!

    Reply
    1. Tim Avatar
      Tim

      I’ve got a Hybrid/ 29er with these forks, had it for about three years, I like them. I even go off road occasionally and they handle rough terrain and the odd tame jump better than you would expect. Maintenance consists of a squirt of shock lube when I remember and they have been trouble free. Don’t be put off by the concerns of people who haven’t tried them, they do what they are supposed to do very well.

      Reply
      1. Jens Avatar
        Jens

        Hi,
        great that there is some recent feedback on this thread. I’m looking to put this into my son’s Trek 7/2 FX. He is complaining about the fork being to stiff, well he is 13 and went from a 24″ cheap MTB to a 7.2 FX… he likes the fast ride, but doesn;t care for the arm jolts he gets going up on the side walks when crossing streets.
        I fund this fork and was wondering if anyone has put it in any new or recent version of the Trek bikes.
        I’m still waiting for some answers from Trek on diameter and stem hghtof the trek bike.
        I told my son his arms will get stronger with time riding his new bike, but I like to have done as much research as possible before I (have him paying for it) purchase this fork.
        Thanks Jens

        Reply
        1. Andy Avatar
          Andy

          This is what I have to tell people at the bike shop constantly: before you look into some fancy new gadget or rare part for a “solution,” try the normal things first.

          Riding on sidewalks is actually illegal in many municipalities. It’s been shown to be 3x as dangerous as riding in the road. I won’t elaborate on safety further, but will leave that to him/you. If the sidewalk bumps are annoying, there is a nicely paved road that is safer and legal to ride on next to it, which I would highly recommend regardless.

          Normal bike fixes to deal with bumps include using wider tires, which don’t necessarily have to be thick rubber either. Check out Panaracer Paselas. It’s a great tire, often as low as $20, but comes in wider widths without being super rugged “touring” tires. Keep in mind that the more they use words like durable, puncture resistant, or touring, the thicker the rubber will be and the more sluggish they will feel on a nice road.

          He should also get the bike fit properly. If he’s felling a jolt on bumps, I’d guess his arms must be locked straight. A proper fit keeps your arms slightly bent, so that you can absorb the shocks through your muscles instead of your bones.

          Good luck.

          Reply
          1. Jens Avatar
            Jens

            Thanks for the info. Yes I told him about the arm position and that eventually he will get used to it.
            As for you safety concerns in riding on the sidewalks … well I don’t know where you live, but in my neck of the woods (Minnesota US) which is considered one of the finer cities to ride because of its trail/ sidewalk system, car drivers think “they are entitled to the road and bikes have to be on the sidewalk”. Cars do not keep the 3 feet distance to bikers on the road. And I know because I do ride my road bike on the road, where I have a right to be.
            A 13 year old or for that matter most kids do not have the capabilities of riding very straight, fast and exercising the same foresite, us adults with drivers licenses have.
            So I think the safest place for any child riding a bike is the sidewalk or trail, at least in suburia USA.

            Reply
            1. Andy Avatar
              Andy

              Read some studies. Use real data. Sidewalk riding is 3x more dangerous.

          2. Jens Avatar
            Jens

            I agree with you, that sidewalk riding is more dangerous for the reasons mentioend in some of the studies. But in surburban America, where the identification between trail and the wide suurban sidewalk aren’t clear and where you hardly find people walking around like on a sidewalk in Chicago or New York City downtown the factor of dangerous becomes a lot lower. Combine this with street traffic going 40 – 50+ mph without real sholders and ignorant car drivers … I would ignore the studies and be safe on the sidewalk.

            Reply
            1. Andy Avatar
              Andy

              Anecdotes vs facts. I can keep repeating this all day: Read some studies. Use real data. Sidewalk riding is 3x more dangerous.

            2. Tim Avatar
              Tim

              Getting a bit off topic here guys, back to the forks… I get away with a lot with mine by riding with a little finesse and remembering that these are a lightweight item. If your son crashes up and down curbs like my son used to then these might not be ideal, they can handle more vertical force than you’d expect but a horizontal impact might might get ugly.

            3. Jens Avatar
              Jens

              Thanks Tim, actually we went on a 27 mile bike ride today and he handled it pretty good, not even wearing bike gloves. I think he is getting used to the forks and we might be okay.

  20. SR Suntour Swing Shock – one for the 29er crowd? | Mutterings, Trends | Muddymoles: Mountain biking (MTB) in the Surrey Hills and Mole Valley

    […] but that’s a separate discussion. This post is all about the news that Suntour have developed a short travel suspension fork for the commuter/road/fixie […]

    Reply

Leave a Reply to Morpheous Cancel reply

Your email address will not be published. Required fields are marked *