Re-rethinking Suspension: the Red Shift Shockstop

Re-rethinking Suspension: the Red Shift Shockstop

Back when mountain bikes had 73-degree head tube angles, stems had quills and were at least 120mm long and wheels were only 26-inches in diameter, one of the early suspension ideas was the Allsop suspension stem. It featured a parallelogram design and a spring so that the bar would drop when you hit a bump. The marketing materials worked from the logic that you only needed to suspend the rider, not the whole bike.

Okay, we know that’s silly, but seriously, you can stop laughing now. Here’s a hanky to wipe your eyes.

Aw heck, there’s this other side to that stem. Everyone who rode one said it was better than no suspension at all. There just wasn’t enough travel for it to soak up the bumps you hit when mountain biking. However, I never saw anyone ask a perfectly reasonable question: Would it help in the case of a road bike hitting potholes? I kinda always wondered.

Miracle of miracles, I have my answer now. Redshift Sports is a component manufacturer known for creating unusual responses to reasonably understandable dilemmas. the Shockstop is a stem with a pivot just ahead of the steering axis. Inside the stem lie two small urethane elastomers that the stem squeezes under load. Included with the stem are six elastomers of a number of different hardnesses, so you can choose between maximum firmness, which feels like some titanium stems I rode in the Long Ago and cushy, which will allow the stem to move through its full travel.

According to Redshift you can get up to 10mm of travel with a flat bar bike, but up to 20mm of travel with a drop bar bike. When you think about the amount of travel you derive from forks by Lauf and Fox, a 20mm travel stem starts to look interesting, at least on paper.

Shockstop goes for $139.99—a whole lot less than a new fork. You can add a computer mount, the Shock Stop Mount for Garmin, Wahoo, Joule, Polar and more, for just $29.99.

I’m riding with a 110mm stem with a -6-degree angle. The stem comes in four lengths: 90, 100, 110 and 120mm in a +/- 6, as well as a 100mm length with a +/- 30 angle. The bore diameter is 31.8mm, but they offer shims for 25.4 and 26.0mm. It comes in all the different hues of black. Our stem weighed in at 291 grams.

For purposes of my riding, I installed the two softest bumpers, partly just to see how noticeable the stem movement would be, and if its movement would be disturbing. And of course, I was curious to see if I felt there was a positive benefit.

Let me be clear: In your first ride on this stem, you are likely to hate it. It’s different, very different. And it’s a kind of difference that you are unlikely to find appealing. I had to keep an open mind and stay out for more than 10 miles.

I began with a couple of road rides just to see if bar movement resulting from hitting a pothole or pavement seam would cause any problems with handling. The answer was a reasonably quick no. While that part didn’t surprise me all that much, what did surprise me was the fact that I really only sensed actual bar movement when my hands were on the brake hoods. When in the drops or on the bar top, the sense I had was that the front tire was soft, like you experience with a slow leak.

Out of the saddle, I could feel the stem’s movement, but unless I was really throwing my upper body around, weighting and unweighting the front wheel, I didn’t detect much in the way of movement, certainly not enough to cause me to sit down or reduce my effort.

Recently, I met up with a bunch of friends to ride some of our favorite dirt roads in Western Sonoma County. My litmus test for great gear is that generally, it should disappear into the background of your ride experience. Some items deserve to call your attention, but at a point, anything you change on your bike should help make your experience more seamless and transparent.

On our descent to Austin Creek, a switchbacky affair with a single singletrack line down an old fire road I punched through any number of bumps, over branches and around rocks. With my hands in the drops I never once experienced my attention being drawn to the stem movement and the real trial came during the very end of that descent with my drop into the creek and my ride across those river stones to the far bank.

I’ve just finished a weekend of racing cyclocross—three races in three days, and I rode the bike with this stem all three days. My upper body is reasonably sore, but what I’m not experiencing is the nerve pain I’d expect from all the shock I delivered my neck from the great many bumps I hit. Call me a believer.

My only question is when they will do a tricked-out light version.

Final thought: I could see the day coming when I have one on each of my drop-bar bikes.

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  1. Ron Reed

    I built up a road bike with an Allsop stem for my girlfriend, back in the day, and it rode incredibly well.
    More recently I’ve also been waiting for the carbon fiber super duper version of this stem.

  2. Winky

    The more things change, the more they stay the same. I like this concept much more than the stupidly complex and proprietary Spesh system. These things will never be as good as a suspension fork on really rough stuff, as they don’t suspend the front of the bike, but they’ll be lighter, cheaper and seemingly an advantage over a rigid stem for some people/applications. This one looks OK, too.

  3. Jim

    I’d guess the stem helped make the bumpy grass areas of Sunday’s race more comfortable. Do you feel like it made you faster, and/or offered you more control, say, on the single track descents? Of course, inasmuch as being more comfortable lessens fatigue, it would make sense that it may have helped you be faster late in the race.
    What I’m getting at is that there is a line between the benefit of something like this and the penalty of the added weight, especially in the case of Sunday’s long run-up. It’s a personal thing, sure; everyone has their own threshold. What’s your take on this stem, in that context?

    1. Author

      For me, the first big selling point is reduced jarring of my neck because I have spinal stenosis. I’d like to do whatever I can to avoid surgery. Thanks to the Second Law of Thermodynamics (things go from bad to worse), aging isn’t working out well for any of us, so while many, if not most, riders don’t have the need I do, I’m betting that at some point everyone will. So there’s that. I’m wondering how much this stem could have saved me (in terms of pain and disc compression) if I’d started using it some years ago. All that said, yes, I do think it improved control, basically anyplace the course was bumpy, and given that it was a cyclocross course … it helped nearly everywhere. My sense was that it allowed me to ride over the rocks following the dam with a greater gentleness, and because I was running tubes, I wanted to be super light on my bike. The weight, to me, was beyond worth it.

  4. Fausto

    How would you compare it to the two leading suspension front end frames from Trek and Specialized? In theory it would be a cheap trick to swap on the bike when heading to the occasional rough stuff.

    1. Author

      I’ve got very few miles on the Specialized version and none on the Trek. The guys I know who have ridden the Specialized version love it. That said, the Shockstop is geniuser because it is brand neutral and can be retrofit. And the bike isn’t built around it so you can choose whether you will run it or not.

  5. Mark

    I’ve got a couple of the Alsop stems in my garage. I liked using them with a bullhorn setup on my ancient Bridgestone MTB.

    Question is, how much different is the Redshift from the Girvin Flexstem?

    1. Author

      Ah, the Girvin Flexstem. My memory of that is that it wasn’t terribly well made and the pivot would develop slop over time. Maybe that was a function of mountain biking, or maybe it was manufacturing quality, or maybe it was just something you noticed with a 60cm-wide bar. But on paper, not a lot of difference.

  6. Mark

    Also to add to my previous comment, JP Morgan (out of the North Bay, I believe) had worked on not only parallelogram suspension stems (with dampers- the comment I remember from him was that he had problems dissipating enough heat with early versions of his damper), but he also made some setups with a slider in the steerer tube and a link in front to prevent twisting. Sort of like an upside down Cannondale Headshock, but smaller and without the fiddly linear roller bearings.

    I don’t know what else he’s been up to since I got out of the bike biz in the nineties. Having him drop by the shop riding one of his prototypes was more exciting than a visit from a sales rep with new products.

  7. Sean Runnette

    Gulp. Ordered one based on this review. Excited and a bit nervous, but mostly curious. Thanks very much for dipping your toe into this weird lil corner of tech.

  8. Steve

    Comments from the past:
    1. I don’t remember any 73 degree head angles, but Bridgestone did popularize the 71/73 head/seat tube geometry.
    2. This is more like the Girven Flexstem with its single pivot.
    3. I’ve used both single pivot and quad pivot stems, and liked both of them for the same reason; they can be retrofitted to most bikes.
    4. In the collection, I’ve got a JP Morgan CNC’d Allsop copy-anybody remember him from Sausalito?

    1. Author

      There were plenty of mountain bikes with 73-degree head angles. Way too many. But credit Grant Peterson with always doing what he thought was smartest. Bridgestones handled great. And true, it *is* more like the Girvin.

      Two mentions of JP Morgan in the comments. Wow. Okay, here’s the challenge: Everyone who has any of JP Morgan’s stuff needs to email shots of the parts to me. That’s worth a post.

    2. Steve

      OK, name 5-10 and I’ll do some research-just because I don’t remember something doesn’t mean it didn’t occur!
      My MB-1s did handle great, but weren’t anywhere near as comfortable as earlier 68 degree head angle bikes like my Ritchey…
      JP Morgan pics went to [email protected]

  9. MattC

    The only downside I can see to this (other than the weight penalty, which is offset by how much less you get beat up) is something I learned with a Manitou fork eons ago: the elastomers give is temperature dependent. The colder it gets the less they give. If you were to do cold weather riding your flex would get closer to zero as it gets colder (I rode my Manitou on my old KHS Montana mtb on the frozen lakes of Illinois/Wisconsin, and I can attest that it had ZERO suspension in below freezing temps). Maybe this isn’t a problem with most of us (these days I’m pretty much a “fair weather” rider. But then something happens and I’m out in the snow seeing what I can get out of my 2.3″ wide tires. I would venture to say that in colder/frozen weather, the suspension of the stem would be MORE necessary which is the opposite of what you get. Thus some kind of oil/spring unit would be welcome. Maybe they’re working on it as we speak?

  10. Ron Reed

    I asked the RedShift guys about temperature sensitivity some time ago and they responded that with current elastomer technology this would not be an issue, barring extremes.

  11. Andrew

    The Riding Gravel website did a long review of this a little while ago. Short version- they liked it. You should be able to find the review easily by searching. I’m fairly tempted to get one of these, but my X4 on my gravel bike is SO pretty…

  12. Grego

    After riding with one of these stems on my 23mm-tired road bike for a couple weeks, I’ve concluded that the damping is worth the minor weight penalty. The only time I notice the stem is when pulling up to hop a curb or such, where unloading the stem slightly increases the necessary pull to get over the obstacle. It feels different but hasn’t been a problem.

  13. Ross

    I have a 6-level c-spine fusion. Lots of bone grafts, rods and screws. Every ride hurts to some degree – yeah, I should probably find another pastime, but whatever. I’ll will try anything within reason to dampen front end buzz and impacts within the constraints of a standard drop bar road bike. Thick tape, bar padding and 30mm tires help, but this stem has been transformational for me. Rough tarmac, broken pavement, gravel, and even concrete apron seams are comfortably muted, especially on the hoods where you spend the most time. I’m under 140 lbs, and use the elastomers recommended for <115 lbs which gives the most compliance. I was used to the bar movement after the first ride. I don't even notice it climbing on the hoods or sprinting in the drops. If this thing weighed twice as much, I'd still use it. If you have any similar neck issues, or possibly even wrist or shoulder problems, the Stopshock is worth a try. It works.

  14. Twisted Spoke

    Count me in. I’m 61 with tight neck and shoulder issues and a new gravel bike. I’ve already determined that I really really miss my full suspension bike when the trail is more than just gravel. The reviews for the Redshift suspension stem are across the board positive and the stem looks nice in terms of styling. Elastomers have come a long way, too. I had a chance to talk with one of the Redshift engineers at Interbike last week and came away impressed. This think looks well designed and constructed.

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