The Reasons By Mohammed Edward and Josh How

The Reasons By: Mohammed, Edward, and Josh

How can we see the world through the eyes of a physicist?

Entrance Ticket What is the best gear combination for going uphill? A bigger cog in the back or a smaller one in the back?

What We Learned ● ● One bike does not fit all Aerodynamics Tires are crucial for creating friction Spokes help carry the weight of the rider, w/out them the wheel would bend

One Bike Does Not Fit All ● One bike cannot meet all the needs of the different styles of biking. ● Different people have a plethora of various needs that can be satisfied by only certain types of bikes.

Why Bother w/ Aerodynamics? ● Air is not weightless ● Aerodynamic position allows for the biker to cut through the air and travel faster.

What part does the tire play in moving the bike forward? ● Due to Newton’s third law, the tire exerts force on the ground which also exerts an equal force back onto the tire which propels it forward ● Friction also keeps the bike on the ground allows the rider to have better control on the speed and traction

Spokes ● You cannot think about the bike without thinking about the rider ● Spokes on the wheels of the bike are tuned to support the weight of the rider ● If there were no spokes on wheels, wheels would bend inward and break due to the massive force on them. ● You would also be unable to attach the wheel to the bike without the spokes.

Frame We chose the Scattante XRL Comp Road frame because it was a nice combination of sleek and sturdy. Aluminum, a lightweight metal, in the frame’s design justifies it’s durability and lightweight quality. This particular model is the commonly used and classic diamond shaped frame design. One of the main issues that this model overcomes is aerodynamic drag. Aerodynamic drag is one of the main forces that someone on a bike needs to overcome. The slender shape of the design makes it so that the rider has less frontal area and makes it easier for the rider to cut through the air causing faster speeds with less effort. Frontal area represents the rider’s position on the bike and aerodynamics of both the rider and the bicycle. Being aerodynamic means that the object is light (needs less upward push), has lift (the force opposite of the weight), has less drag (drag is the force that tries to slow things down, less drag can be achieved by having a narrower shape), and it must have thrust ( the force opposite of the drag that pushes forward). It doesn't have the biggest mass and its shape is able to keep the rider in a position where he has a slightly arched back, consequently decreasing his frontal area. Less frontal area means a narrower shape. This results in a more aerodynamic shape. We chose a frame with an adjustable seat height to add or subtract drag depending on the bikers needs and wants. More drag means a better workout, less means a more comfortable commute. The frame’s lightweight design will suit both the consumer’s commuting needs and exercise needs as it will make commuting a cinch and allow the consumer to go particularly fast when cycling. Being able to adjust the amount of drag adds to the appeal of the bike as a source of exercise. The bike’s aerodynamic nature, as previously stated, makes the trip to work a lot less of a hassle because the rider will not have to battle with the resisting force of the drag.

Fork The fork came with the frame itself so it is the perfect fit for the frame. It is slightly bent forward so that the frame is a bit lower to accommodate different sized riders. This curve also reduces trail, thus making it easier to turn. Trail is the horizontal distance from where the steering axis intersects the ground to where the front wheel touches the ground. This comes in handy when commuting as there may be various obstacles to get around and turns to make. The fork also gets skinny to the ends and since the ends are facing more outward, this does help in gaining speed and slicing through air, another advantage when used for exercise.

Handle Bars The FSA Omega handlebars that we chose are drop handlebars. They are curved inward on the ends so that when you hold them your knuckles are facing outward. This helps because it allows for easier turning. When your hands are closer to the end of the handle, you will not need as much effort to turn the bike and you can change hand positions easily, preventing fatigue. If the rider’s hands get sore after being the same place for a while then they can just change positions making the ride pleasant and not annoying. Additionally, this shape allows the rider to assume an aerodynamic position, an aerodynamic position that can be achieved by making the torso as flat as possible and tucking your head in. This position makes the surface of the rider a lot smoother, consequently providing less drag. Our bar is also aerodynamic in that it does not have much frontal area for the wind to go against.

Tire The Forte Strada K Road Tires are very good for speed on the road. They have an almost totally smooth exterior that allows for maximum speeds. As previously stated before, smoother surfaces decrease the amount of drag. There is sufficient friction on the tires when biking on the road due to the contact patch. A bigger contact patch means more surface area on the tire for friction. More friction would have been great, however we feel that just as long as there is enough, the rider will enjoy the bike’s friction and controlled movement. It is not too big but is enough to provide the controlled movements that accompany proper adhesion and friction. The tires are also slim and sleek in shape so you will easily be able to cut through air if you ever find yourself in a race. The tread is good and won’t allow for slips. This tire is an all around tire essentially, perfect for commuting and for exercising.

Wheel The Wheel Master bicycle wheels have many tuned spokes that keep the rim from bending into a concave shape. The spokes are tuned because they support weight on the wheel. Because of the size of the wheel you will be able to reach high speeds quickly and with less effort as you start biking. The wheels are also light keeping your bike as light as possible. Being as light as possible is a desirable characteristic of being aerodynamic as we have stated before. There is more tension in the part closest to the ground because it takes the most.

Pedals We chose standard pedals so we could accommodate every shoe size and type. These pedals will use the force of your feet’s pushing and use it to propel the bike forward. With regular pedals you can easily bike in sneakers and regular shoes depending on your needs at that current moment. If you commute to work with a bike you want a bike that fits and accommodates all your needs that way you just need to dismount and get to work. Clipless pedals are used more for mountain biking and aggressive biking. Additionally, you would need to change shoes constantly due to the design of the clipless pedal. It would be a hassle to commute to work on a bike if you needed to change shoes after each use.

Crank The Retrospec Bicycles Fixed Gear Crank is a single speed crank. We believed that a regular commuter would not need any very big changes to gears because he is probably not climbing mountains going to work. We have put an 8 -speed cassette in the back and that will help with the occasional hill. We also do not want to make the journey too easy on the consumer because we want the consumer to burn calories while commuting.

Cassette The SRAM PG 850 Speed Cassette is an 8 -speed that will greatly help with the occasional hill. While it may not be the best for going up a steep one, it will get the job done. The 8 -speed gives a bit of choice to the rider. It allows him to choose how hard he wants to bike and the speed he wants to bike at. With a bigger back cog, it will require less strength to turn the wheel and will take you a smaller distance per cycle. If you use a smaller cog in the back, you won’t need more cycles to go the same distance but it will be much harder on your legs per cycle. With a choice like this, you can go up any road the way you want to tackle it. This will come in handy when the consumer wants to exert a lot of force during exercise or less for commuting.

Brake We chose to only put one brake on the bike because you don’t need to stop too much if you are only biking on the road. The model we chose is the Shimano Acera Mountain Bicycle V- Brake. The V- brake is a type of rim brake. Rim brakes apply braking force via friction pads to the rim of the tire in order to halt the bike’s movement. Kinetic energy is turned into thermal energy during this process. Rim brakes are light, powerful, and easy to maintain. Our brake is quick to respond and will stop the fastest of bikes. The brake clamp is a highquality rubber that has a lot of friction for stopping the wheel. We put this brake on the back wheel because you won’t flip if its on the back if you are going at fast speeds. If you brake too quickly on the front wheel while going at high speeds, your bike will flip forward resulting in you landing on your face.