![\"ccs-62657-0-60883100-1539697251.jpg\"](\"https:\/\/wp-media.bikehub.co.za\/production\/uploads\/2023\/02\/ccs-62657-0-60883100-1539697251.jpg\" "\\"\\"")
<\/a>Image credit: Craig Kolesky.<\/span><\/p>\nBalancing descending capabilities with climbing prowess is not unique to mountain biking, it can be one of the more complex. How can it be more complex than something with an engine and a million moving parts? Well\u2026 mostly because its engine doesn\u2019t stand still. Why does this matter? Well, when the engine is jumping up and down on the pedals, and moving all about in the turns, it\u2019s a little difficult to design a system that counteracts all of those inputs to make the \u201cultra-efficient\u201d bike that the marketing loves to preach.<\/p>\n
It gets worse\u2026 forgetting your e-bike for a second, unlike a car or motorbike, you can\u2019t plug the bicycle\u2019s engine into a power socket, or fill it up at the petrol station. Instead, its engine requires training, nutrition, recovery, and often TLC to get it through a rough day on the trails. Most other forms of transportation are far more simple to refuel (and cheaper) and as such also far easier to keep running.<\/p>\n
Why does this matter? Well, what it means is that when designing bicycle suspension, what may seem like a simple task is made infinitely more difficult by the fact that as a rider you are more complex than the most advanced engine. Added to this, engineers need to consider making the bicycle efficient at riding over terrain, but also efficient at transferring the power produced by its owner.<\/p>\n
So lets talk suspension:<\/strong> Front suspension (hardtails) are almost as rare as a bicycle industry \u201cstandard\u201d, with fully rigid bikes reserved for beach cruisers and hippies. For these articles, we will forget about these two categories so that we can dig into the real \u201cjuice\u201d of mountain bikes, full suspension designs.<\/p>\n Front suspension is a simple and concentrated category where almost all linkage style front suspension systems died with good music and dial-up internet. These days \u201ctelescopic\u201d designs rule the roost, and are available in a myriad of forms with the same essential, predictable movement up and down.<\/p>\n What is a telescopic design? Well like a pop out umbrella, whether single clamp, triple clamp, upside down or single sided, all telescopic forks allow the front wheel to slide up and down in a single, linear plane. The angle of this is determined by the head angle of the bicycle, the control determined by the damping control of the suspension, and the resistive force provided by the spring (whether air or coil).<\/p>\n Rear suspension is different, and beautifully complex. The way that the motion of the rear wheel is handled, and how that force is transferred into the rear shock can become complicated by many different pivot, linkage and swingarm arrangements.<\/p>\n These \u201ccomplications\u201d are what give full suspension bicycle designs their \u201cmechanical advantage\u201d over a hardtail, and the performance traits we\u2019ve all come to love. But we don\u2019t fully understand our current suspension design, then how do we know its performing right? And more importantly, how do we know it\u2019s right for us? Well\u2026 read on!<\/p>\n Why have suspension?<\/strong><\/p>\n Two reasons: efficiency and control. What\u2019s most interesting about these two things is that they are almost complete opposites. Suspension makes your bicycle more \u201cefficient\u201d by allowing the wheels to move out of the way when they impact an obstacle. This is more energy efficient than the work required to move the entire system (bicycle & rider). On the other hand, suspension improves your \u201ccontrol\u201d by keeping the wheels in contact with the ground thus improving the traction of the tyres giving better cornering, braking and acceleration.<\/p>\n Well that sounds simple enough right? But just think about that for a second, forget the additional things that are secondary benefits to suspension (comfort, cool factor etc). Ultimately, the purpose of your suspension is to allow your wheels to move out of the way of obstacles, and to keep them in contact with the ground. This may sound like a contradiction, but this is the most important thing to understand, is that it\u2019s this fine balance that is at the very centre of suspension, the ability of the wheels to move out of the way of obstacles must be controlled, and so too must the wheels ability to track the terrain and maintain contact with it.<\/p>\n What are the downsides? <\/strong>First up price, weight and maintenance. Full suspension systems tend to weigh more because there are linkages, pivots, shocks, and a more complex set of components needed. Because of this added complexity and the moving parts which make it, the durability of a full suspension bicycle is always going to be less than that of a hardtail because there is more to go wrong. The additional cost of this complexity is well\u2026 the cost. These parts are often precision made, and the fact that there are more components, more engineering, more materials means there is more expense.<\/p>\n Arguably though, the main downside of rear suspension designs for bicycles is energy efficiency. Remember you\u2019re the engine, meaning that we don\u2019t want to waste energy. For other vehicle suspension systems, this isn\u2019t such a problem because there is typically a real engine, however, on a bicycle, the power comes from the rider, who has a finite amount of energy which we want to conserve.<\/p>\n Quick! Get the popcorn!<\/strong> I said \u201cefficiency and control\u201d were reasons to have suspension, then why did I just say there is a loss of efficiency? Well as we learned in physics: \u201cThe total energy of an isolated system remains constant, energy can be neither created nor destroyed, rather it can only be transformed from one form into another\u201d.<\/p>\n So what does this mean on your bicycle? Well\u2026 imagine for a moment that you and your bike have kinetic energy when rolling down a hill. When your wheels hit an object and the suspension allows them to move out of the way of that object some of this energy is transferred into heat as the suspension plays its part in absorbing this impact. The efficiency comes in thanks to the fact that the energy transfer to heat to displace the wheels is less than what would be transferred in order to displace the entire bicycle with you on it. Hence this is more efficient as more of the kinetic energy is maintained. But, when you\u2019re then jumping on the pedals trying to get that KOM your movement up and down, and your force on the pedals also causes movement in the suspension which in turn translates to some conversion into heat as the suspension compresses and extends. This causes some loss of efficiency, and this is the first balancing act!<\/p>\n Go carts vs Dakar trucks<\/strong>: Alongside efficiency is control, and to do this the rear suspension should provide the right amount of \u2018support\u2019 so that good handling of the bicycle is maintained through the suspension travel. If the wheel just gave way to the object that it needed to absorb then it would also give way when you needed it to push back into the ground in order to maintain contact and give you control. This is the second balancing act!<\/p>\n Balancing the requirements of bump absorption, energy efficiency and support is part of what makes any vehicle suspension design complex, but what makes a mountain bike suspension design even more complicated is that the physics used to optimise these two balancing acts is an equation with an ever-changing variable \u2013 you. To spice things up more, we also love to throw in different disciplines, riding styles, terrain etc, making the \u201cperfect\u201d design infinitely complex, and ultimately up to interpretation.<\/p>\n What the force? Your back wheel is acted on by 6 main forces, and in most cases, these are where energy is transformed \/ transferred:<\/p>\n In the simplest terms, the point of a rear suspension system is to maintain contact with the ground be it by absorbing bumps or by tracking the terrain, this is ultimately the requirement. The other aspects are negatives and designs must try to mitigate these without too largely impacting the benefit.<\/p>\n But wait, like any good T.V. series here\u2019s the closing catch: Force 2, the drive force, can be both beneficial and detrimental depending on how it is applied. To find out more, tune into the next episode!<\/p>\n Andre van Aarde is the Managing Director of cycling distribution company Rush Sports<\/a>. Before founding Rush Sports, Andre worked at Morewood Bikes where he gained insight into mountain bike design. As an enthusiastic mountain biker, Andre has travelled the world riding bikes including taking part<\/a> in an EWS event.\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":" Welcome to our new suspension tech series where the aim is to break down the mechanics behind suspension, translating the tongue-twisting jargon that fills most bike websites and forums into layman\u2019s terms. In Part 1, we answer a fundamental question: what is the purpose of rear suspension? Virtual Pivot Point, anti-squat, horst link, falling rate, […]<\/p>\n","protected":false},"author":3,"featured_media":28612,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[478],"featured_location":[],"class_list":["post-15643","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tech","tag-suspension-series"],"_links":{"self":[{"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/posts\/15643","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/comments?post=15643"}],"version-history":[{"count":0,"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/posts\/15643\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/media\/28612"}],"wp:attachment":[{"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/media?parent=15643"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/categories?post=15643"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/tags?post=15643"},{"taxonomy":"featured_location","embeddable":true,"href":"https:\/\/bikehub.co.za\/news\/wp-json\/wp\/v2\/featured_location?post=15643"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}<\/a>Sam Bull’s body position in the turn above perfectly demonstrates one of the many complexities bike engineers are forced to consider when designing suspension systems. Image credit: Troy Davies<\/span><\/p>\nThe complexity of two<\/h2>\n
<\/a>Photo credit: Craig Kolesky.<\/span><\/p>\n<\/a>On rocky terrain, suspension acts to keep the wheels in contact with the ground, maintaining traction. Image: Craig Kolesky<\/span><\/p>\nThe balancing of odds<\/h2>\n
Drawing a conclusion<\/h2>\n
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<\/a>The diagram above shows the six main forces numbered as they relate to the list. Image: Pete Fogden.<\/span><\/p>\n<\/a>\n<\/div>\nAbout the Author:<\/h2>\n