What material helps the bike frame adapt to the mountain environment?
Bicycle frames are the main component of a bicycle as parts like wheels are attached to it. Because bike frames is the most important part of a bicycle, it is important that it can sustain and adapt to the environment that you are biking in. In this case, we are looking at a bicycle frame that will help mountain bikers adapt to the rough environment. To get a picture of what is going on inside a frame designers head when they’re thinking about building a bike frame, we have to look at something called ‘The Builders Triangle’.
So when builders or designers or whomever are making a bike, they’re trying to balance three things that are all interrelated. First is stiffness, the second is weight and the third is strength. And when you change one of these aspects, the others also get changed, for instance, if you add more material to a bike to make it stiffer, you’re also going to increase its strength and you’re also going to increase its weight. But on the other hand, if you want to make the bike lighter by using less material in the bike frame, you’re going to make it lighter but you’re also going to make it less stiff which means you’re also going to make it less strong which means that’s its going to be more prone to dents and buckling and other not so fun stuff. Builders consider three things when they’re trying to balance their ‘builder’s triangle’. The first thing they consider in this triangle is material, the second thing they consider is the tubing diameter, and third, the tubing wall thickness. So builders try to balance these three things to make a stiff enough bike that is strong enough but also that will be light enough. By choosing the right material, the right tubing diameter, and the right tubing wall thickness, they achieve the perfect bike that is supposed to adapt to the type of biking you are doing.
The first part of the ‘Builders Triangle’ is stiffness. We use the word stiffness and throw it around a lot and a lot of times, we don’t really know exactly what we’re talking about as stiffness is a vague word, especially in biking. But usually in biking, it means the amount of flex of frame gives during the pedal stroke and while riding over bumps. A synonym for stiffness can be ‘malleable’ as it has to adapt to the bumps and the mountain terrain. According to Rei.com, an expert advice bike page says that steel frames are generally considered to be less stiff than aluminum frames. But steel as a material itself is stiffer than aluminum. But nevertheless, steel frames are less stiff than aluminum frames. This is because steel frames tend to have a smaller diameter tubing and thinner side walls because a builder can only make the diameter of steel tubes so big, and the tubing so thin, before they risk the frame failing with regular use. Aluminum frames on the other hand have bigger diameter tubings and thicker sidewalls. Giving these frames thicker characteristics. Frame builders can do this with aluminum by using more material without making the bike too dense because aluminum has one-third the density of steel. To summarize stiffness, aluminum frames are stiffer because of how they’re designed. They have thicker and bigger tubes than steel frames. But, there’s a couple of misconceptions about stiffness itself. The first misconception is that stiffer frames mean less comfort. But this really isn’t all that true because comfort doesn’t really come from your frame. To a certain extent it does but comfort mainly comes from your size to bike ratio like if you are too big for your bike or if the bike is too big for you. Comfort also comes from tire pressure such as how high or low the tire pressure is. There are more misconceptions on if stiffness affects how comfortable you are but your size to bike ratio and the tire pressure are the main ones. The second misconception about stiffness is that less stiff frames are slower because they are less efficient at power transfer. But according to bike expert who refers to himself as a bike genius, Sheldon Brown says that steel frames act as a really efficient spring, so when the frame flexes, eventually all of that energy that is lost in the frame is not actually lost and it gets transferred to this place called the drivetrain interior rear wheel.
The second part of the Builder’s Triangle is weight. Even though builders use more material when constructing aluminum frames, because aluminum has one third the density of steel, aluminum frames of comparable quality tend to be lighter than steel. And they key here is comparable quality. A bike review site called ThoughtCo said that a mid to high-quality steel frame will be lighter than a low-quality aluminum frame because of budding. Budding just means that some parts of the tube have more material than other parts to add strength while reducing the overall weight of the frame. To summarize weight, steel frames are denser than aluminum if both materials are the same quality. And in mountain biking, density is important because you have to adapt to the unusual track and ride through the abusive terrain and density helps it sustain the mountain environment.
The third part of the Builder’s Triangle is strength. When we’re talking about how strong a bike is, we’re really referring to two things. How durable the bike is and how much abuse the bike can handle. In material engineering, there’s this fancy word called ‘fatigue strength’. Fatigue strength is the material’s ability to survive repetitive forces like pedal strokes. Because steel acts as a spring, and has an infinite fatigue strength, no matter how many times you apply the same force to steel, it won’t break. If the steel doesn’t break the first time, it won’t break any other time. For example, say your steel bike frame was lying on the floor and you somehow drop a whole piano on top of your bike frame. If the piano does not damage the steel bike frame, no matter how many more attempts you throw your piano at your bike frame, it won’t break because of steel’s infinite fatigue strength. Aluminum on the other has a limited fatigue strength. And if you use it enough times, it will eventually break. Aluminum bike frames are not the best option in mountain biking because aluminum will fail with enough use. The second part of strength is durability and how much abuse the l frame can handle. Steel can really take a beating and it is the most reliable material you can make a bike out of. Because it relies the most amount of force before bending or breaking, this means that you could generally be rougher on steel bike frames as they can handle more abuse than aluminum bike frames. Steel bike frames are also more likely to survive a crash. Because aluminum is less dense, it is a softer material which means that it will get things like dents more easily. These dents are weak points where the frame is more likely to crack, bend or snap. Aluminum frames are more fragile than steel frames so you have to be careful while you are mountain biking.
In conclusion, I think that for mountain biking, steel frames are better than aluminum frames. This is because steel is not that stiff compared to aluminum. In mountain biking, stiffness is import because it mainly supports you while you are riding over bumps and when you are biking at a fast pace. If your bike frame was stiff, the movement of the bike would be limited and this would cause more accidents and cause you to constantly have trouble while you are mountain biking. The next aspect is weight. Steel is 3 times denser than aluminum which means that steel frames are going to help you adapt to the mountain terrain as it can be abusive and rough. The last aspect in why steel frames are better than aluminum frames is because that it is more durable and it can handle more force and more roughness. Steel has an infinite fatigue strength which is important when you are being rough with the abusive terrain. This means that your bike won’t be dented, bent or even snap like aluminum bike frames. Mountain bikes can be really expensive and if your bike does not break for about 5 years you won’t be regretting buying that bike because with aluminum mountain bikes, you would have to get it fixed or get a new bike constantly because aluminum can’t handle roughness. Steel frames are also better than aluminum frames because of their economic issues. Encyclopedia Britannica states that steel is the most used material in bike frames today and this makes it the cheapest material. This is important because it means that when people are buying a new mountain bike, they are getting the best material for the mountain bike frame but they are also not wasting their money. This is because an aluminum bike frame costs more than a steel bike frame but you will be getting your money’s worth with the steel bike frame because steel won’t break for around 5 years. But the aluminum bike frame has the potential to break and snap in around 6 months. Another factor that matters when you are buying a mountain bike is the environmental factor. I’m more focusing on things like the environmental aspects that will affect the frame itself. Things such as the frame rusting and the frame heating. A lot of people think that aluminum is better for wet-conditioned riding because aluminum doesn’t rust. A mountain bike site called dirtmountainbike.com confirms that aluminum does not rust because rust refers to oxidized iron and iron is found in steel. Although aluminum doesn’t rust, it does corrode. And corrosion to aluminum is just as devastating as rust is to steel. So even though aluminum does not rust, it does corrode. The next environmental aspect which affects both materials is heat from the sun. Heat affects steel but it does not affect aluminum. When heat meets steel, it expands it. This is a problem because steel is really dense and its tubing diameter is meant to be small so it does not become that heavy. But heat is going to cause steel to expand, causing it to become denser everytime you take a ride. This is an issue caused by the environment because it means that your bike is going to be slower and stiffer causing you to be more prone to injuries and accidents. To summarize the economic factors and the environmental factors, steel is cheaper than aluminum because steel is currently the most used material in bike frames but a steel bike frame will become dense from the heat as heat will expand the steel causing it to be denser. To conclude the factors, there will never be a perfect material that will be the best in every aspect because every material has its pros and cons.
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