Last time, we talked about Anti-Squat, which is a frame’s rear suspension design’s resistance to compression under acceleration and pedaling forces. This week, we talk about Anti-Rise. While it sounds like a simple inverse, it’s actually quite different as it has little to do with pedaling force, and much more to do with braking forces and the subsequent shift of your weight.

For this installment, we have answers from Chris Currie (President, Speedgoat Designs and the guy behind the new Jamis 3VO suspension), Christophe R. Benoit (MTB Engineer, Cycles Devinci), Tim Krueger (Managing Partner, Esker Cycles), Tyler Cloward (Director of Product Development, Fezzari) and George Parry (Engineering Manager, Niner Bikes),  (Tim Krueger, ) and (

BIKERUMOR: In simple terms, what is “Anti-Rise”?

BENOIT: When braking, the force created by the decelerating mass of the rider causes the rear end to ‘rise’. The Anti-Rise is the propensity of a suspension to stay active under braking conditions by counteracting this brake jack using appropriate pivot placement. It’s simple geometry.

KRUEGER: Well, it could mean a few things in this context, but in the bicycle world, it generally refers to the concept of designing a suspension not to extend under braking forces. So, that would be the trait of a suspension system that resists suspension extension under mass (meaning “weight”) transfer during braking.

Currie: These days, mostly a marketing term. First, understand that it’s relative. “Anti-rise” isn’t a feature found on only some bikes. Whether you’re seeing the term “anti-rise” or “anti-dive” (opposite way of measuring the same basic thing), all suspension systems with rear brakes have it. One bike will have more “anti-rise” than another, but if your wheel goes up and down when you hit stuff and you have a rear brake, you’re in on the party. It’s usually better to set aside the vague terms and instead think about how your bike behaves. There are three kinds of bikes in the world when it comes to squeezing your rear brake lever: ones that compress their rear suspension or “dive,” ones that firm up their rear suspension or “rise,” and ones that ignore the brake and let the suspension work the same whether the brake is being applied or not.

How does Anti-Rise and Anti-Squat affect full suspension mountain bike performance
Currie’s diagram, showing how the combination of, literally, everything about your bike and you affects the Anti-Rise. It’s position shown here at full extension, read on to see what this means.

BIKERUMOR: If you had to explain it more technically, is there anything you need to add to that description to help people understand the concept better? (as in, if a bike has “50%” anti-rise, what does that number mean?)

CURRIE: First, visualize this: when you accelerate (pedal) or decelerate (hit the rear brake), you’re a giant bag of meat and water sloshing backward or forward, so it’s up to the pivot locations and link dimensions of your suspension system to deal with that mass. “Anti-rise” behavior (braking) and “anti-squat” behavior (pedaling) are both calculated relative to a “center of gravity,” or basically where that giant bag of meat and water that is you happens to be at any given moment.

Drawings go a long way to help with this, so I put together a hypothetical bike using Linkage, a program used by a lot of designers for calculations. On a bicycle the vertical height of that “center of gravity” is very important. Check it out as the line labeled “CG” on the screen captures. The center of gravity or “CG” can be viewed as a horizontal line many bike nerds believe lives 600-800mm above your bottom bracket center. This is not a true fixed point (because people come in different shapes and sizes, and they move around). Really bitchin’ suspension systems like 3VO account for this.

How does Anti-Rise and Anti-Squat affect full suspension mountain bike performance

To start working out anti-rise, first draw a horizontal line straight through that center of gravity point, then draw a vertical line straight up from your front axle. Next, we need to draw some lines through our pivots to find the “instant center,” or the point at which those lines intersect. Those are the bright purple lines shown in the close-up detail images (below), and the actual instant center is shown in bright green.

Diagram showing a full suspension mountain bikes instant center with explanation
Instant center with the suspension fully extended on the left, and fully compressed on the right.

To find anti-rise, start at the point our rear tire contacts the ground and draw a line up through that “instant center” and keep on drawing. Where that angled line crosses the vertical line up from your front axle will be either above or below your center of gravity line. Dead center on that line would be 100% anti-rise. The hypothetical example bike shown has an anti-rise of 116.8% at full extension (no rider on it), and an anti-rise of 80.4% at full compression. For this example, the bike sits right around 100% anti-rise through most of it’s travel. Clear? Of course not. Back to some marketing? I designed my 3VO system to hover right around that 100% zone so it can ignore the rear brake–not dive and not rise–while still absorbing impacts the same way it does when the brake isn’t on.

PARRY: When the rider is braking the center of gravity shifts forward (inertial force) causing the fork to compress and the rear suspension to extend. This will happen even if the rider shifts his weight back on the bike. More than 100% anti-rise implies that, under rear braking only, the suspension will compress. Conversely, less than 100% anti-rise implies that, under rear braking only, the suspension will extend.

CLOWARD: When the brakes are applied on a bike, depending on the design of the suspension, it will pull up on the rear wheel and compress the rear suspension. The higher the anti-rise number the more the rear suspension will compress. 50% anti-rise is pretty low and braking will have a smaller effect on the suspension and the suspension will remain active. At 100% the suspension will compress under braking. At 150% the suspension will compress even more and can cause a lockout feel while braking over bumps.

BIKERUMOR: What’s the benefit of Anti-Rise to the rider?

BENOIT: The main goal of Anti-Rise is to keep an active suspension under braking.

KRUEGER: Well, we talk about it a bit differently today. We used to call it anti-rise as the braking forces wanted to extend the rear suspension. Then, as people began to understand it a bit more, and design ways to counteract, we started calling it “brake stiffening” a bit more in that the suspension wasnt so much extending any more, but stiffening up under braking. Basically, the difference between extension and stiffening wasnt much, really those are the same forces, just with stiffening being less of an impact on the frame than extension. Now, we generally talk about “brake isolation”, basically trying as much as possible to remove the forces of braking from have any effect whatsoever on the suspension. So, coming back full circle, “brake isolation” could also be described as 100% anti-rise mathematically.

I believe the term anti-rise is still used in the CAD program Linkage – which is probably why it is coming up here, but suspension engineers are not actually using Linkage, so that term is not really used a lot in kinematics discussions anymore. An interesting note here, while 100% anti-rise would mathematically make sense to isolate brake forces, that’s not actually what feels best in the real world. And what that number is, and what the curves look like is what a lot of companies try to protect and/or keep secret. A well designed bike in this area will feel “muted” under hard braking, and not really have any reaction to the application of the brakes, especially in regards to suspension performance.

Keegan Wright riding the 2019 Devinci Spartan 29
Getting the anti-rise performance dialed on the new Devinci Spartan 29er helps keep Keegan Wright from going ass over elbows!

BIKERUMOR: Is there a downside?

KRUEGER: In this case, not really. Again, in a perfect world, we would have 100% anti-rise (or perfect brake isolation) at every given point in the travel (or, the magic number that actually feels best to riders), but thats not truly possible. So, we look at how the bike is going to be used, and dial in those optimal points for the best traits. Again, like anti-squat, some of those specific traits, curves or points are protected and patented.

BENOIT: Suspension kinematics are a mix of many factors including Anti-Squat, Axle Path, Leverage Ratio, and Frame Design (Clearance, shock placement, geo, and frame stiffness). Tuning each of these aspects has an effect on the others. Therefore, we need to balance all these variable to reach our desired suspension performances. The split pivot platform allows us to reach the optimal tune since the brake is mounted on a link that is independent from wheel movement, thus separating the braking forces from the acceleration forces.

The Esker Elkat gets 150mm of rear travel that has to be kept in check under hard braking
The Esker Elkat gets 150mm of rear travel that, like all full suspension mountain bikes, has to be kept in check under hard braking.

BIKERUMOR: How much Anti-Rise do you want?

CURRIE: Just the right amount. Seriously, this is kind of the secret sauce – especially since anti-rise is affected by rear axle position. It changes as your suspension compresses. Personally, I think it’s best to have that change be minimal, so behavior under braking is consistent throughout the full range of rear wheel travel. That’s what I did with 3VO.

BENOIT: Keep the Anti-Rise in a zone that prevents the suspension from stiffening under braking. It’s hard to give a specific value since anti-rise is measured along the travel and changes depending on the bike’s intended use.

KRUEGER: The real numbers and curves are secret – but in ride experience terms – you want enough to prevent suspension stiffening or extension under braking, but not so much as to create a lot of suspension compression under braking.

BIKERUMOR: How do you design Anti-Rise into a frame?

PARRY: Similar to anti-squat, anti-rise is determined by the position of the suspension pivots. As with anti-squat, anti-rise is just one of several variables that must be considered for a balance suspension design.

KRUEGER: This is where the real fun begins, when we talk about how to counter braking forces in a frame AND acceleration forces. There are a lot of people out there now who say with single chainrings, multi-link bikes are useless and we can all go single-pivot. The truth is that the theoretical points in space that we use for designing anti-squat and anti-rise are different. It is possible to make a single pivot behave extremely well for one of the two traits with proper pivot placement, but it is impossible to make it behave well for both traits, as that would require two seperate pivot placements, one for acceleration, one for braking. This is where mutli-link bikes come in.

Any multi-link bike can be designed to have a varying “instant center”, or the particular point in space the theoretical pivot is, at a given point in the travel. These instant centers are important to both anti-squat and anti-rise, and some multi-link designs are more “tuneable” than other designs. So, any suspension design that has the wheel mounted to a swingarm, with a link on either side of the swingarm attached to the frame uses the idea of the “instant center” These are designs such as FSR, DW-Link, Switch Infinity, Orion or VPP. Single pivot bikes don’t do this, as they have a “real center”, i.e., the pivot is the actual center, all the time. Any bike where the wheel is attached to a swingarm, and the other end of that swingarm is directly attached to the main frame is a single pivot, even if the execution appears like a multi-link. Those are what are typically referred to as “faux-bar”. In faux-bar or single pivot executions, you can typically dial in the behaviour for one of these two traits, but not both.

CURRIE: Very carefully and usually while other people are asleep.


The fun never ends. Stay tuned for a new post each week that explores one small suspension tech, tuning or product topic. Check out past posts here. Got a question you want answered? Email us. Want your brand or product featured? We can do that too.

20 COMMENTS

  1. These articles are great. Once again, the different opinions of the various designers is interesting to see. One individual claims 100% is the goal, whereas others clearly feel that less than 100% is optimal. You can buy Linkage for ~$30 and it is a lot of fun to check out various designs. Based on my random sample of the “best” bikes out there, I would say that many of the big guns aim for less than 100% antirise. Thanks to the participants and BikeRumor for putting these discussions together.

  2. These complex load and spring design is where electronically controlled spring should be handy. Some accelerometer and precise software controlled springs would both simplify the mechanical design and make it track closer to ideal. It has a lot more potential than a single electronically controlled on-off spring on Pinerello K10-S road bike.

  3. Interesting that only one person mentioned the braking forces causing the rear suspension to compress…

    I think this is what most people call “brake jack”. Even though the “jack” name seems to imply it should be lifting the bike, usually when hearing about “brake jack” you also hear about the suspension stiffening. This is probably from the torque on the wheel under braking wanting to rotate the swing arm towards full compression, making it feel stiffer as the shock gets further into the travel. If there were only the weight transfer forward, causing the suspension to extend, there wouldn’t be any stiffening.

    • They did address suspension compressing under braking, however I was disappointed that they didn’t really talk about the upside of it. Even though the suspension is compressing and there is less available travel, it will help preserve the geometry of the bike under braking, keeping it more level and compensating for the fork compressing from weight transfer. There have been a number of torque arm/floating brake systems over the years that allowed the rider to tune anti-rise and, from what I’ve seen, different riders preferred different settings.

      Regarding your second point, about defining terms like “brake jack” I’ve noticed the same thing in that bike journalists either don’t understand the variability of the concept, or they do a poor job expressing it. Even worse though, check this out from the article:

      “PARRY: More than 100% anti-rise implies that, under rear braking only, the suspension will compress. Conversely, less than 100% anti-rise implies that, under rear braking only, the suspension will extend.”

      “CLOWARD: The higher the anti-rise number the more the rear suspension will compress. 50% anti-rise is pretty low and braking will have a smaller effect on the suspension and the suspension will remain active. At 100% the suspension will compress under braking. At 150% the suspension will compress even more and can cause a lockout feel while braking over bumps.”

      See the contradiction there? And that is simply talking about a % value, which should be more clearcut than a term like “brake jack” or “stinkbug”. Hopefully these guys understand the numbers and are just better at engineering than expressing their knowledge in writing.

      I was also disappointed in inconsistencies in what people consider to be “active” under braking. Over the years there have also been bikes where brake torque actively extended the suspension, not just not compensating for weight shift, but actually pushing the swingarm down. That is what I’d term “brake jack” and I am left confused as to what % value they’d assign to that.

      • This is also just wrong:
        “PARRY: When the rider is braking the center of gravity shifts forward (inertial force) causing the fork to compress and the rear suspension to extend. This will happen even if the rider shifts his weight back on the bike.”

        cog can theoretically stay fixed and weight transfer will still occur as one must sum moments against the acceleration force with the contact patch reactive forces. If a rider shifts their weight back, their cog may in fact be farther back (and lower) from their pre-brake position. However, suspension dive may still occur due to weight transfer to counter the moments.

        I’ll give Parry the benefit of the doubt in trying to explain physics in a soundbite. But it does display the the issue I highlighted in my comment below. A fixed % of anti-rise or anti-squat means little to nothing in practice. To have a fixed number, one must also fixed cog, which is not possible. One can market a fixed number as “best” but it only applies to a rider with that exact cg and mass at all times (I think mass could be negated if one’s sag % and spring curve rates where identical, the later I think is impossible).
        I know designers know this but when people talk they inevitably start asking about the ideal % value (and this article confirms that to some degree). This is a disservice to end-users that will gravitate to that theoretical “best” and it WILL affect their judgement on what works best since they are not blind testing bikes.

        Finally, I would like to know how the 3VO design accounts for varying cog’s. That is amazing if actually true. Maybe it just isn’t very sensitive within a reasonable cog range?

        • This is what happens when you dumb down the words. His parenthesis gives the right idea though. CoG doesn’t have to shift, but the rider’s inertial force is going forward. Maybe he’s imagining a test dummy as a rider… xD

  4. I stated this on the anti-squat article:

    Although the kinematics are useful from a designer’s standpoint, they are all but useless for the end-user. There are too many variables to say that “x” bike has the correct anti-squat or anti-rise. Why? Rider style, rider weight, rider height, rider c.o.g., terrain, preferences for feel. These are all assumptions a designer must make and they won’t hit all of them. Additionally all suspension designs are a trade-off in one respect or another (performance, weight, complexity, maintenance, stiffness, cost, etc)

    Almost all modern mtb’s are good. They all have their specific traits. Take two good mountain bikes and give them to various people, and in general you will have split preferences.
    So – test ride!!! What works for one, may not work for you. The “ideal” or “best” suspension design per marketing or an article may not be “ideal” or “best for you. Ride what works best for you and what feels best for you.

    • They spoke about the “anti-rise” tuning to the bike’s intended application extensively above. And yes, test ride. Bikes are no longer good or bad, they are now the flavor you seek. A good time to be a rider.

    • Agreed. What’s most interesting about these discussions is the engineers want to/need to quantify everything, but at the end of the day, the real test is human perception, which is about as mushy a variable as possible. So you’ve got the engineers on one end with their maths, and you’ve got the end user on the other with their often-irrational brains and meat bodies. And what’s in between? The marketing departments.

    • Could not agree more, All modern bikes are good and in fact probably better than most people on them. All this ‘gumf’, it’s just more endless marketing BS trying to one up the next guy and add more smoke to the mirrored room; because the physics and dynamics that drive all this have been known for a very long time. As much as ‘bicycle’ people like to deny it, a fully sprung mtb has much in common with it’s powered cousins and the dynamics behind those, especially the effects of weight transfer and braking forces, have been worked out for a good while.

      @JBikes: This is also just wrong:
      “PARRY: When the rider is braking the center of gravity shifts forward (inertial force) causing the fork to compress and the rear suspension to extend. This will happen even if the rider shifts his weight back on the bike.”

      I will though say you got this bit wrong. What Parry states here is true and an effect of front end braking. Where up to 70% of braking goes through the front wheel, the COG of the bike (as a whole) shifts forward and the forward momentum being arrested is absorbed by the forks. This causes the rear end to un-weight and effectively jack up as the shock uncompresses. Pretty basic physics really. Anti fork dive tech used in motos, especially GP bikes, is used to arrest this helping keep the geom from drastically changing, which can lead to the front wheel ‘folding’ especially in corners.

      • No I didn’t get it wrong. Check your physics/statics. The forks primarily compress due to the weight transfer, not the cog of changing. This is evidenced by the fact that one can have zero cog change and still compress forks due to deceleration (this actually requires one to shift backward as compressing forks will change cog by themselves)

        If one does a force summation, one will see that even with rigid forks and a fixed cog, weight transfer occurs and is the reason why front brakes do most of the work.

        Do a force summation on a box that only touches the ground in two spots (like wheels) undergoing deceleration or acceleration. In order to cancel the moment the elevated cog causes while acelerating/decelerating (f=ma), the front on decel or rear on accel must see higher reactionary force to counter the moment. This is the weight shift. Fork compression adds to it as it will naturally move cog forward (but humans can counter that by moving backward)

        That said, one still benefits from anti-fork dive and I wasn’t stating otherwise—simply its not simply due to change of c.o.g.

      • Much simpler:
        What causes the initial fork compression…weight transfer due to deceleration, not cog change.
        The fork compression tends to cause cog to move forward which compounds the force on the fork resulting in more compression but the primary reason was deceleration regardless of cog since that can technically stay the same if a rider shifts position.

  5. Really interesting article, but it’s funny how far apart these guys are in their discussion. There are mutually exclusive statements–both statements cannot be true–being made by different parties. I assume they’re all competent MTB engineers, so I guess it comes down to terminology–people using the same words to mean different things. Benoit’s claim (in multiple paragraphs) that anti-rise makes a rear suspension more active goes against my layperson’s understanding of anti-rise; it must be a terminology thing.

  6. To the people prying for a specific #, they’re all implying it should be a range. If you plot it out, the anti-rise will change as the suspension compresses, perhaps creating a curve. Consider that it also changes as the rider moves…

    They’ve implied that how much you want at any point in the travel is personal preference…

    I imagine that you want high anti-rise, especially at the early and mid stroke, when you demand geo be stable under braking and want to maintain a forward charging position. Anti-rise should decrease deeper in travel.

    I imagine those that like to hang off the back of the bike during braking want lower anti-rise to keep things more active in such a case.

    • Maybe geo forces people to ride forward (short chainstays, long front) or behind the saddle (long chainstays, short front). Tuning the braking to this would be considerate…

      I doubt designers design per bike size, but instead per bike model and just add/subtract an inch here and there from the geo. They probably figure it should be close enough to whatever size they prototyped (typically large). Just be being pessimistic, but considering they keep stuff like this secret, it’s hard to believe that the industry has things figured out, or is too cheap to pay for man-hours to such value to put such value in, instead spending time refining aesthetics. xD

      • “I doubt designers design per bike size” they don’t.

        It’s usually based on the middle size… Shocks as well are not tuned to the different sizes/weights, you just go with the ‘average’ and whack it into all the sizes.

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