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I remember in the early 1990s contemplating getting a suspension stem for my 1989 non-suspended Rockhopper MTB.

suspension stem

I'm surprised that suspension stems appear to have essentially disappeared. Why? They seemed a cheap and easy solution to give a bike front suspension. They could also be made lighter than suspension forks. What were the negatives?

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    I understand they had pretty "terrible handling" because the rider might push or pull on the bars leading to the stem moving. Plus they were made with elastomers and not springs. In the 90s elastomers were glorified rubber bands with a relatively short life span, and once its torn or otherwise dead, then the stem is just a big wobbly parallelogram. And they have more metal so more weight. Seatpost suspension is still a thing though.
    – Criggie
    Feb 7, 2017 at 4:44
  • Can I put your comment in an answer Criggie LOL I don't have anything much better. Feb 7, 2017 at 5:14
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    With the advent of kickstarter etc new attempts have been and if you look around you will find 3 or 4. Some of those only have 1 or 2 mm of play, Another requires you to have a huge amount to post available for mounting. None are cheap. Feb 7, 2017 at 5:38
  • @Craig a couple of mm world be nice on dirt roads etc. on a hybrid, but I'd never go for it without understanding the potential failure modes. Failing to a bit rattly in the vertical direction is one thing, making the steering sloppy is another.
    – Chris H
    Feb 7, 2017 at 8:21

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Former Alsop Suspension Stem rider here... as much as I respect everyone's answers above I can say that Alsop suspension stem advocates would disagree with some of the assertions.

Alsop's motto was "suspend the rider not the bike". So as far as having to decouple light-weight moving parts from heavy stable parts for suspension to work... That is exactly what an Alsop does, decouples the rider from the frequency vibration of the bike.

Alsop stems, at least the later models, were spring loaded not polymer loaded. They traveled as a parallelogram giving about an inch to an inch and a half of travel.

The parallelogram motion of the Alsop is what set them apart from competing suspension stems. Other suspension stems (Girvin Flex Stem) used a swing/pivot point which limited the overall travel and rotated the handlebars along an arc during compression. Limited travel and rotating controls led to the demise of the competition long before Alsop succumbed to the suspension fork.

At the time I loved my Alsop Frankenstem... the problem and what eventually caused me to walk away from the product was they tended to wear out fast. Bushings constantly needed to be serviced. Additionally, they were susceptible to catastrophic failure. Over the course of 3 years I had 2 stems fail... horrible crashes and stitches were the result so I spent the better part of the next 20 years riding rigid bikes.

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    100mm is about four inches so your conversion is off somewhere. Great answer though!!
    – RoboKaren
    Feb 7, 2017 at 22:17
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    Ouch! I've never had a stem fail ever, and any bike failures have been gradual, not been sudden and unexpected. Once would put me off the product permanently.
    – Criggie
    Feb 8, 2017 at 2:26
  • @RoboKaren wow you are absolutely correct... I am usually pretty good at math... I corrected the above.
    – dafew
    Feb 8, 2017 at 13:51
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    Forget about "suspend the rider not the bike"; a more accurate motto for a product that hospitalized you twice in three years would have been "dump the rider in the gutter." Feb 8, 2017 at 22:10
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To make suspension effective, it must decouple light-weight moving parts from heavy stable parts. For this reason it is most effective to suspend the wheels - they will move fast up and down, while the frame and the rider will not move vertically. A suspension stem is not very effective because it does not carry much vertical load. A suspension seat post is better but will never work as well as wheel suspension.

You can observe the same principle in cars: light-weight aluminium rims are better for suspension than heavier steel rims.

In sort: suspension stems are ineffective for suspension, add weight and complexity, and potentially dangerous failure modes.

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    You can probably also add that your arms are already decoupling the motion of the handlebars from the motion of the rest of your body. Feb 7, 2017 at 13:31
  • An average rider is 80kg vs a bike at about 12kg (spread over 2 wheels), a front fork/wheel at 2kg of unsuspended weight, so the difference between suspending the whole bike vs just the wheel is much less than this answer suggests.
    – mattnz
    Feb 7, 2017 at 22:21
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I see suspension stems making a comeback. If you do some searching you can find lots of examples. However, they aren't usually found on mountain bikes because they provide nowhere close to the amount of of travel that today's mountain bikers demand. Most of them provide under 20mm of travel, while mountain bike forks usually provide at a minimum 80mm of travel. However, the suspension stems are getting somewhat popular with the gravel grinding trend that is gaining popularity, or even in places where the quality of asphalt leaves something to be desired.

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  • I see them now being sold for roadbikes. I could see their popularity when travelling over cobblestone roads!
    – RoboKaren
    Feb 8, 2017 at 19:05
  • Can you add some pictures from modern examples into your post? I feel like that would really improve the answer. Apr 17, 2017 at 18:33
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I was thinking back to the 1990s when I was looking at these suspension stems and remembered why I didn't get them then:

1) Price. I was a starving student and couldn't afford them. Many were as expensive as my bike itself.

2) Brakes. Like many mountain bikes at the time, I had cantilever brakes. These required a fixed position above the brakes for the brakes to pull against -- for the front brakes, it was the handlebar stem. So if I switched to a suspension stem, I'd have to get a brake bridge or go to another type of brake. That would add to the cost.

Cantilever brake

Those were the reasons I didn't get them at the time. Now, mtbs have switched to disc brakes or V-brakes, so the brakes aren't a reason to get them.

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    On the other hand, cost was a major reason they existed - they might have been expensive for a student, but they were a lot cheaper than buying a suspension fork, which probably meant a whole new bike, since rigid forks at the time typically weren't "suspension corrected".
    – armb
    Feb 13, 2017 at 10:11
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They work more like a damping of the shock rather than absorbing it. Shocks might weight more but are good for down hill. I had a Girvin for my road bike and it was down to weight. It worked well on poor bumpy road conditions and gave better control through damping.

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