The mini bike was a very complex product with different components that varied in complexity themselves. The bike consisted components such as a chassis, a frame, an internal combustion engine, and a carburetor. The components of the mini bike varied in ease of disassembly as well. A scale of 1-5 was used to represent the ease of disassembly of each piece. A 1 indicates that the component was very easily taken apart, requiring no tools, and low amounts of force to disassemble the component. A 5 would indicate that the component was very hard to take apart, requiring numerous tools, and a lot of force to disassemble that component.
- In order to remove the plastic chassis from the mini bike’s frame, a P1 Phillips screwdriver, a P2 Phillips screwdriver, a socket wrench with a 10mm socket and a 15/16” socket, and a pair of needle nose pliers were needed. The removal of the chassis had a complexity of 2. First, to take off each of the side panels, one 10mm hex screw with a washer was removed with the socket wrench, two ½” screws were removed with a P1 Phillips screwdriver, and one ¾” screw with a 10mm hex nut sandwiching a rubber washer and a metal washer was removed using a P2 Phillips screwdriver. Next three ¾” screws were removed from the front mud guard with the P2 Phillips screwdriver. All three screws had ½” diameter metal washers. To remove the seat from the frame of the mini bike, two ¾” screws with washers were removed from the underside of the seat with a P2 Phillips screwdriver. This was a more complex step because the screwdriver had to be maneuvered into the space under the seat, which was very cramped. Next, one ½” screw was removed with the P2 Phillips screwdriver to remove the front cover of the mini bike. Two 1” hex screws with ¾” diameter washers were removed from the plastic gas tank with a P2 Phillips screwdriver. Finally, two ½” screws with metal washer were removed with a P2 Phillips screwdriver to remove the plastic guard over the chain.
- To clear the frame of all parts that were to be further disassembled, a socket wrench with 8mm and 12mm sockets, a 1/8” flathead screwdriver, and needle nose pliers were needed. The entire frame was a complexity of 3 to disassemble. One 4” screw with a metal washer and nut was removed from the top of the engine with the 13mm socket wrench. Next, all of the electrical cords were removed or unclipped where possible. In order to remove the chain from the engine to the back wheel, the master link in the chain had to be located. When this was located, the cover was removed by hand, and the link was opened using the flathead screwdriver. Two bolts with washers were removed from the spiral spring on the rear suspension by hand. This was a particularly complicated task because it was necessary to apply pressure to the suspension in order to make the bolts able to be removed. In addition, it was necessary that the chain was removed before taking off the rear suspension.
- Removing the kickstand had a complexity of 1, requiring only a P2 Phillips screwdriver to disassemble. The kickstand was connected to the engine with four 1 ¾” P2 Phillips screws. Also, it was necessary to remove the spring connected to the kickstand and the engine before removing the kickstand itself. Failing to do so resulted in the spring shooting out from the bike.
Engine Block: 5
Image of Side View of Engine
- The engine block was the most complex component of the mini bike with a complexity of 5. This is because many of the parts were very tightly sealed; there was also oil covering most of the engine block making the process more difficult. In order to disassemble the engine block, a socket wrench with 8mm, 10mm, 13mm, 14mm, and 17mm sockets was needed. Two 2 ½” screws were removed from where the carburetor and spacer are connected to the elbow joint with a 10mm socket wrench. Then, we replaced the screws into the carburetor with the spacer. Next, remove the elbow joint from the engine block by removing two 1 1/8” screws with a 10mm socket wrench. The front cover of the engine block (where the carburetor meets the engine) is removed by unscrewing four screw caps with washers with a 10mm socket wrench. Next, a 4 ½” bolt connecting a silver cap and a hex nut is removed using a 10mm socket wrench. To remove this bolt, it is necessary to hold the silver cap in place, otherwise the nut will not unscrew. Then, use the 8mm socket wrench to remove the two 1” hex screws with welded washers located next to the bolt that was just removed. Remove the 1” hex screw connecting the grey section of the engine block to the black part of the engine block with the 8mm socket wrench. Now we moved to the black part of the engine block. The covering of the spark plug was removed by hand. Once again, we moved down the engine block, now to the final grey part. On the kick start side of the engine, an 8mm socket wrench was used to remove one 3 ¼” bolt, two 2 ¾” bolts, and five 1 ¾” bolts. Next, a 13mm socket wrench was used to remove the hex nut and washer from the gear cover. In order to remove the kick start itself, one 1/8” hex screw was removed with a 10mm socket wrench. The kick start was then pulled off by hand. The same method was used to remove the shifter connected to the transmission. On the side of the engine opposite of the kick start side of the engine, an 8mm socket was used to remove one 3 ¼” bolt, two 2 ¾” bolts, and 5 1 ¾” bolts. Finally, the engine was turned over and two bolts were removed from the bottom. The bolts were a 1” bolt with a washer removed with a 17mm socket wrench, and a 7/8” bolt with a spring removed with a 14mm socket wrench. This was the furthest the engine could be disassembled without risking great damage to the engine. Had we had heavy machinery to disassemble the engine, pistons and more gears would have become visible.
- The carburetor was not a very complicated component, so it had a complexity rating of 2. In order to disassemble the component, needle nose pliers, a 1/8” flathead screwdriver, and a P2 Phillips screwdriver were needed. Before anything was done to the carburetor itself, all 3 pieces of tubing connected to it were removed with needle nose pliers. Next, a P2 Phillips screwdriver was used to loosen one 1 ½” screw from the clamp holder on the air filter. After the air filter is removed, use a P2 Phillips screwdriver to remove 2 ¾” screws with washers from the carburetor cover. Removing the carburetor cover exposed a black piece of plastic connected to a spring, which vibrates to mix air and fuel in the carburetor. This is removed by hand by removing the thin rod above the spring, and removing the spring itself, taking care not to lose the spring connected to it. Next, the internal screws of the carburetor are removed with the 1/8” flathead screwdriver. The hex screw was in the middle, and the smooth screw was offset from the middle. Outside of the carburetor, opposite of the choke, there are two ¾” screws with springs. The diagonal gold screw was removed with a 1/8” flathead screwdriver, and the silver screw parallel to the air intake was removed with a 1/8” flathead screwdriver as well. To remove the choke switch from the carburetor, a ¾” gold screw with a washer fitting into a ¼” sleeve was removed with a P2 Phillips screwdriver. The remaining part of the choke is removed by hand.