Group 6 - Mini-Bike/PPR
Contents |
Causes for Corrective Action
Our group’s system of management and our work proposal require several upgrades to fit the current work situation.
One of the major issues not dealt with in the original planning and execution of the first gate was the matter of specific timelines for completion of the gates of the project. In order to correct this oversight, a Gantt chart has been added to the wiki page explaining our projected completion dates. This chart demonstrates amended work schedules that represent a more realistic yet timely set of goals that must be met in order to successfully complete the gates.
Another concern that needed to be addressed was the weekly team meetings. It was previously agreed that group 6 was to meet Wednesday evenings. Having had more opportunity to scrutinize our schedules, we have discovered that Thursday during lab hours (3:30-6:30) is the optimum time for our group to meet. A problem not originally addressed in the management and work proposal but discovered during the actual work process is the structure of said weekly meetings. Future weekly team meetings shall begin with each member reporting how much progress they have made on their long term projects and if any roadblocks have been encountered. If so we will proceed to work towards solutions of those blocks, then continue by proof reading of all written assignments as a group. Finally, we will end each meeting by assigning new tasks based on past performance and total workload of group members.
Something we did not expect was the fact that disappearing parts have become an issue in the past couple of weeks, with both the gas cap and the muffler of our mini-bike going missing. We have also found that larger parts, such as the front wheel assembly, have been moved around the lab in our absence. Due to Group 6’s specific project, we do not have the option of storing it in another location. Currently, to minimize the risk, we will move the large parts of our product farther away from the trash can area and take all the smaller parts out of the lab. This should curtail the threat somewhat, although we have no way of completely preventing the theft and/or vandalism that is occurring.
Finally, while personal conflict has yet to occur within group 6, the work ethic as well as attendance of group meetings has been poor lately. The new structure of our group meetings should hold members more accountable to their fair share of the work. On the off chance that any personal issues arise however, a plan for dealing with them has been devised to manage said issues depending on the severity and the type of the conflict. In the case of a verbal altercation over work load or quality, the group members not involved in the argument shall determine who was in the right and take whatever corrective action they deem necessary. This egalitarian process allows for a fairer and easier going working environment and will hopefully minimize any resentment. However, if the group cannot come to a consensus, the final decision will go to the group leader. In the case of a non work related verbal altercation, the members involved shall be told to refrain from such unprofessional behavior and be kept away from each other if necessary. If said problem persists to the point where it is affecting our project, it will then be dealt with as a work related problem. Finally, any physical altercation shall be reported to campus police and dealt with by the proper authorities.
Product Dissection Plan
*Note: the break down for the difficulty levels are as follows:
1 = easy, requiring no real thought or awkward positioning, small time span(1-2 minutes).
ex unscrewing a single part that is fully exposed such as the spark plug.
2 = medium, some awkward positioning to get to the part, small time span(1-2 minutes).
ex unscrewing more than two bolts with the bolts not fully exposed such as the combustion chamber dissection.
3 = hard, requiring some very awkward positioning and thought, small to medium time span(1-10 minutes).
ex unscrewing multiple bolts which are significantly hard to get to, such as the carburetor assembly
4 = hard, requiring some thought multiple people wielding tools and a great deal of time,medium time span(3-10 minutes).
ex the locking collar which required a great deal of dexterity and patience to remove
5 = impossible with available tools and expertise.
ex the press fit transmission which required tools outside of the lab.
| Product Dissection By Steps | |||||
|---|---|---|---|---|---|
| Step | Description | Tool Required | Difficulty (1-5) | Photograph of Parts Involved | |
| 1 | Removed the (4) screws from the bottom of the seat to disconnect it from the frame. | 8 mm socket wrench | 2 |  | |
| 2 | Removed the handle grips, brake lever and throttle from the handlebars. | Phillips screwdriver and 10 mm socket wrench | 3 |  | |
| 3 | Removed the front steering assembly | 13 mm and 15 mm socket wrench | 1 |  | |
| 4 | Disengaged the chain from the wheel then removed the chain guard and chain tensioner. | 6 mm Allen key | 2 |  | |
| 5 | Removed the rear fender by unscrewing the (2) bolts. | 10 mm socket wrench | 2 |  | |
| 6 | Removed the rear wheel and axle from the frame, by unscrewing the axle bolt. | 16 mm socket wrench | 2 |  | |
| 7 | Removed the engine and engine plate from the frame by unscrewing the (4) bolts on the bottom. | Hands | 3 |  | |
| 8 | Removed the engine mounted gas tank. | 10 mm socket wrench | 3 |  | |
| 9 | Removed the muffler and muffler cage. | (2) 10 mm socket wrenches | 3 |  | |
| 10 | Removed the pull starter from the side of the engine by unscrewing the single shaft bolt connected to the main shaft of the engine. | 12 mm socket wrench | 1 |  | |
| 11 | Removed the carburetor assembly from the engine. | 6 mm socket wrenches | 3 |  | |
| 12 | Removed the magnetic ring on the engine shaft. | Pin spreader | 4 |  | |
| 13 | Removed the top of the engine's combustion chamber by unscrewing the 6 bolts holding it to the engine block. | 8 mm socket wrenches | 2 |  | |
| 14 | Removed the spark plug and timing mechanism | 16 mm socket wrenches | 1 |  | |
Total dissection time: 3 hours.
Post-Dissection Analysis
- Is the product intended to be taken apart easily?
The mini-bike is quite easy to take apart up until the engine. Standard tools such as metric wrenches and Phillips screwdrivers can disassemble the bike up until the transmission is reached. The bike was disassembled to the point where the frame was bare and the steering, braking and propulsion devices were separated into their most basic components. The engine was disassembled to the point where the combustion chamber was opened up and split into its disparate parts (spark plug,six hex head bolts, combustion top). The transmission is press fit together which would require some kind of prying tool to get off and then some kind of press to reattach. Therefore the products engine is obviously not meant to be taken apart easily while as individual parts can be replaced on the frame of the bike.
-Hurdles and Disappointments
There were a few tough spots in this dissection. The first came when we lacked the proper tool to remove some springs. In order to combat this problem, Garth Lester purchased a pin spreader tool in order to allow further dissection. The second major hurdle prevented taking the transmission apart. This was a major disappointment to the group as they all wanted to see the internals, including the clutch assembly. There were two parts that prevented the dissection. The first was a lock nut. The nut had teeth on the inner edge that prevented the nut from being turned counterclockwise. The group could not even nudge it even with all five members using their combined forces. The second part preventing assembly was a factory pressed part. It would be impossible to get off without using a factory press. There were thoughts of removing it with blunt force via a hammer. These thoughts were quickly quelled when it was realized that there would be no way to put the part back on without a press. The group spent two hours in addition to the three previous dissection hours trying to move forward. It was finally decided that there was nothing they could due given the circumstances, and we moved on to work on this report. This step is considered level five difficulty since it was impossible to complete with the current tools and expertise.
- What fasteners are used and why?
The fasteners used are: hex head metric bolts sizes 8mm, 10mm, 12mm, 13mm, 15mm and 16mm. These standard metric bolts are used for ease of replacement and removal. They are put in all places where the bolt head does not need to blend into the surface such as on the engine. The hex head bolts are also in all of the places where high torque is applied when fastening since hex head bolts are so much harder to strip then Phillips head.
Phillips screws. These common screws are used for ease of replacement and removal. They are put in places where a smooth surface is desired such as on the brake lever.
Locking collar. This is used to hold on the magnetic collar and is not so easy to replace or remove so that the magnetic ring stays in place even with all the vibration from the engine shaft it rest on.
- Are special tools required?
A Pin spreader was used to remove the locking collar holding on the magnetic ring and post dissection it was found out that a bearing puller would of likely taken apart the transmission
