Group 32 - Honda IC Engine - 2
Group 5 and group 32 were assigned the Honda CBR600F2 bike engine. The purpose of this project was to become familiar with the process of analyzing product design and manufacturing. It also allowed the members of this group to become familiar with combustion engines. The steps of this project are as follows:
- Initial Study: The engine was examined and members shared their initial thoughts
- Disassembly: Every step was recorded and parts were organized to facilitate reassembly
- Analysis of Components: The function, material, manufacturing process, and general description of ech part was documented
- Reassembly: Again, every step was recorded
- Revisit to Analysis - Thoughts for Improvment: After understanding our product, the group thought of improvements on the design
- Development of this Information Page: This page was developed to show the steps taken in this project
- Steven Kapturowski (Group Leader, Presentation, Disassembly)
- Chris Deptula
- Sam Brown (Wiki Page Development, Disassembly, Assembly)
- Kyle Stillwell (Disassembly/Assembly)
- David Pels (Animation Development, Part Modeling, Video Recording)
- David Olson (Group Leader, Presentation, Animation Development)
- Mike Pelino
- Priyambada Parajuli (Disassembly/Assembly)
- Rassell D'Silva Green (Disassembly, Photogaphy, Video Recording)
- Bilal Mohideen
- Manufacturer - Honda Powersports
- Model - 1994 CBR600F2 Engine
- Initial Condition - Non-functional. Not able to test the engine.
This section should include an introduction of the product and a brief description of group members (i.e. who was responsible for which sections or tasks)
Before Disassembly Section
-The purpose of our product is to provide power to the 1994 Honda CBR600F2 sportbike, to run its electronic components and provide propulsion.
-Initially, the energy is stored in the fuel, which is released through combustion inside the piston cylinders. This release of energy acts as a controlled explosion and pushes on the pistons, converting the chemical energy into mechanical work. The mechanical work is transferred to the final drive systems (rotation of wheels). Finally, the friction forces between the wheels and the road propel the bike.
-Estimated Number of Parts: 400
-The bike engines components were made up of metals, plastics, ceramics, and rubberized fiber-braided material.
- AIR CLEANER DISASSEMBY:
- Air cleaner cover was removed by loosening 6 screws.
- Air cleaner element was taken out of the housing by hand.
- Lower air cleaner assembly was removed from the base by loosening 6 screws.
- Air cleaner base was taken off of the carburetor by loosening 16 screw/washers.
- (All screws loosened with a phillips head screw driver.)
- Difficulty: Air cleaner was quite easy to dismantle, very few screws to remove.
- CARBURETOR DISASSEMBLY:
- Carburetor assembly, containing all 4 carburetor components was pulled of the cylinder head by hand, after loosening the ring fasteners.
- NOTE: Carburetor assembly includes 4 identical components. Only one was disassembled.
- Carb. component top was removed by unscrewing the pan screw.
- Spring and vacuum piston and spring were pulled out by hand.
- Carburetor housing was separated by loosening the specialty screw set and the float was removed from the float chamber set.
- (All screws loosened with a phillips head screw driver.)
- Difficulty: Carburetor was more one of the more challenging components of the engine. Taking it apart involved removing many springs and small components.
- COVERS AND EXTERNAL PARTS:
- Water pump was removed from the side of the crankcase by loosening the two long flange bolts.
- Clutch lever and receiver were removed from right crankcase cover.
- Alternator cover (loosening 9 flange bolts) and right crankcase cover (loosening 12 flange bolts) were removed.
- (A socket wrench was used to loosen all the bolts.)
- Difficulty: Covers and waer pump were taken of the crankcase very easily.
- CYLINDER HEAD DISASSEMBLY:
- Cylinder head cover was taken off the head by removing 6 specialty head cover bolts.
- Breather plate removed from head by loosening flange bolts.
- Cam chain (timing chain) was taken off the gear ends of cam shafts and the sprocket of the crankshaft, disconnecting the cams and the crankshaft.
- Camshaft covers were taken off by removing 10 flange bolts from both covers. These bolts were secured to the inside of the head.
- Cam shafts were removed from head by hand.
- Cylinder head was removed from the crankcase by loosening 10 socket bolts and 2 flange bolt, exposing the pistons.
- The gasket sealing the gap between the head and crankcase was removed.
- (A socket wrench was used to loosen all of the bolts.)
- NOTE: Valves were ceased in the head.
- Difficulty: Consisted of larger parts, with exception to valve assemblies, making this disassembly step easier.
- CRANKCASE DISASSEMBLY AND OIL PAN:
- Oil pan was taken off of the bottom of the crank case, exposing the oil strainer and relief valve.
- Upper crankcase housinig was taken off the lower housing by loosening 10 flange bolts from the body and 16 sealing bolts around the edge of the crankcase.
- Removing the upper crank case housing exposed the transmission and crankshaft.
- (A socket wrench was used to loosen all bolts.)
- Difficulty: Involved removing and keeping track of many bolts and there proper location, making this step long but not very difficult.
- CRANKSHAFT AND PISTONS:
- Connecting rod tops were removed from the rest of the rod by loosening the nuts and bolts.
- Connecting rods were seen to be connected to the crankshaft with only the connecting rod bearings.
- Crankshaft was removed from crankcase by hand.
- Pistons were pushed out of cylinders from the end where the cylinder head would be.
- NOTE: The 4 pistons were identical so only one was disassembled.
- Piston's circular clamps and pin were taken out by hand.
- (A socket wrench was used to loosen all bolts.)
- Difficulty: It was easy to take apart the connecting rods and remove the crankshaft.
- CLUTCH ASSEMBLY:
- Lifter plate (cross shaped plate) was released from the press plate by loosening 4 flange bolts.
- Under the lifter plate, clutch springs were now also able to be removed, by hand.
- Center clutch housing was pulled out from within the clutch disks by hand.
- Clutch press plate and disks were removed from outer clutch housing.
- Friction disks and separation plates were pulled off the clutch press plate, by hand.
- Difficulty: The clutch was made up of many parts and fasteners. Dismantling and keeping track of the components was time consuming.
- TOOLS USED:
- Allen Wrench
- Socket Wrench
- Rubber Mallet (necessary to dislodge 2 of the pistons)
|Part Number||Part Name||Number of Parts of this Type||Included Parts||Part Material||Fabrication Process||Images and CG|
|MV9: 1 & 2||Water Pump||1||Housing (2), Hose (1), Bolt Fastener (5), Gasket (1), Clamp (2)||Aluminum||Casting||Assembled Internal Schematic|
|-||Piston||4||Piston Ring (3), Piston Head (1), Pin (1), Connecting Rod (1), Connecting Rod Bolt (2), Connecting Rod Nut (2), Rod Bearing (1), Pin Bearing (2)||Cast Iron||Casting||Assembled|
|9 R1 C EX cam 1, G R1 C IN cam 2, MV9 for sprockets||Cam Shaft||2||Cam Shaft (2), Cam Gears (2), Bolts (4), Cam Brackets (2), Header, Header Gasket||Steel||Casting||Digital Assembly Before Disassembly Schematic|
|-||Carburetor||4||Throttle plate (4), Venturi (4), Jet Needle Set(4), Float Chamber(4), Float Set(4), Vacuum Piston(4), Fastener(16), Top cover(4), Head Gsket(4), Housing Gasket(4), Spring(4)||Aluminum||Casting||Assembled Float Set Vacuum Piston Schematic|
|-||Crankshaft||1||Cast alloy crankshaft||Cast steel alloy||Casting, and machining on a lathe. High speed balancing.||Removed Schematic|
|MV9: 003||Air Filter||1||Fuel Hose(1), Air Cleaner (1), Air Cleaner Housing(1), Air Filter(1) ,Air Filter Case(1) ,Duct tube(2) ,Clip(3) ,Hose (3) , Seal(2) , Breather tube(1), 5X16 Screw(10)||Plastic housing, synthetic fiber filtering element||Injections molding||Filter Housing Assembled Schematic|
|MV9: 716 - Cover, MV9: 671 - Stator||Alternator||1||Rotor(1), Stator(1), Rectifier(1), Housing(1), Shaft(1)||Steel, Copper||Casting (housing), Wire Drawing (stator)||Internal Schematic|
|MV9: 931||GearShift Drum||19||Right fork(1), Fork(1), Left fork(1), Drum(1), Shift drum(1), Shaft(1), Stopper(1), Stopper spring(1), Spindle(1), Shift pin(1), Shift spring(1), Stopper washer(1), 14mm washer(1), Bolt 6X14(2), Bearing(1), Roller 4X8(1), Bolt 8X20(1), Circlip 14mm(1)||Steel||Casting||Drum in Crankcase Schematic|
|-||Clutch||37||Sprocket(1), Clutch outer(1), Collar(1), Guide(1), Center clutch(1), Judder Seat(1), Judder spring(1),Friction disk(5), Top friction disk(1), Plate(5), Plate press(1), Clutch lifter plate(1), Clutch lifter rod(1), Clutch lifter spring(4), Bolt 6X28(4), Nut lock 20mm(1), Washer 6mm(4), Washer 22mm(1), Clutch lifter bearing 12X28X7(1), Clutch bearing 35X42X23(1)||Aluminum (housing), Steel (friction disks and clutch plates)||Casting, Machining||Assembled Schematic|
|-||Transmission||45||Mainshaft(1),Plate (1),Countershaft(1), Gear(41T)(1), Gear(16T)(1), Gear(33T)(1), Collar 28mm(1), Gear(17T,19T)(1), Gear(27T)(1), Gear(26T)(1), Collar 28X31X9 (2), Gear(20T)(1), Collar 25X14(1),Gear(24T)(1), Gear(23T)(1), Collar(25X28X13)(1),Gear(25T)(1), Sprocket(15T)(1), Pin(1), Bolt 10mm(1),Washer 25X31X1.5(2), Washer 28X34X1.5(2), Washer 25mm(1), Washer 10.2mm(1), Washer 25mm(1), Washer lock 25mm(1), Washer 28mm(1), Washer Lock 28mm(1), Washer 20X.9(2), Orifice(1), Circlip 25mm(2), Set-ring 62mm(1), Circlip 28mm(2), Bearing(1),Bearing 20X34X16.8(1), Bearing 20mm(1), Bearing 20X24X10(1), Oil seal 40X62X8.4(1), Bolt 6X14(1)||Steel||Casting, Machining||Removed Assembled Schematic|
- Water Pump:
- -The function of the water pump is to cool the engine block by channeling a water/coolant mixture into spaces in the cylinder head. Heat is transferred to the mixture and the mixture is pumped back to the radiator where the heat is dispersed into the air.
- -Like with most motorsport engine components, the water pump housing is made out of cast aluminum, making it durable yet light.
- -The water pump's housing is shaped to merely cover the pump and is the general shape of the internal parts. The housing is low profile to keep the component light, only consisting of a thin cylinder and two large-bore tubes (breathers).
- Cam Shafts:
- -A double overhead camshaft valve train layout is characterized by two camshafts located within the cylinder head, one operating the inlet valves and one operating the exhaust valves. As the engine runs, the crankshaft operates a chain that rotates the gears attached to the camshafts, in turn, turning the camshafts. As they rotate, with extremely precise moments, one camshaft will open a cylinder valve to allow the fuel/air mixture to enter the piston chamber to be ignited. After the fuel has been spent, the other camshaft will open a similar valve that allows the exhaust to exit the engine.
- Air Filter:
- -The Air filter is made of a paper filter element in the form of a flat panel. This filter is placed inside a plastic casing which is connected to the throttle body via an intake tube. Its main use is to filter the air of any particulate elements which could cause mechanical wear or reduce the efficiency of the combustion by mixing with the fuel.
- -An alternator is an electromagnetic device that transforms mechanical energy to electrical energy. It is part of the charging system of an engine that produces electricity. If an alternator dies or malfunctions, the motorcycle will still run for a while directly off of the battery, until all the battery’s power is gone.
- -It consists of a rotor, stator, rectifier, housing, and shaft. The shaft is connected to the engine by a belt and pulleys. The rotor is fixed to the shaft, and consists of a wire bundle wound around an iron core. It also helps to create its own magnetic field.
- - A carburetor is essentially a tube. There is an adjustable plate across the tube called the throttle plate that controls how much air can flow through the tube. At some point in the tube there is a narrowing, called the venturi, and in this narrowing a vacuum is created. In this narrowing there is a hole, called a jet, that lets the vacuum draw in fuel.
- -The idea behind the engine is to burn gasoline to create pressure, and then to turn the pressure into motion. The goal of a carburetor is to mix just the right amount of gasoline with air so that the engine runs properly.
- - As the piston goes down, a low pressure is formed above the piston inside the crankcase. This same low pressure also causes a low pressure inside the carburetor. Since the pressure is higher outside the engine and carburetor, air will rush inside the carburetor and into the engine until the pressure is equalized. The moving air going through the carburetor will pick up fuel through the jet and the fuel will mix with the air. A needle sits in the hole to regulate the fuel flow. The throttle cable or engine vacuum operates the needle up and down to regulate the fuel in the air stream.
- -The carburetor has a moving flap in the venturi to regulate the airflow, a throttle plate. On most carburetors this is where the throttle cable is connected. As the throttle plate is opened it allows more air into the engine. Fuel is fed through a fixed jet controlling the amount of fuel.
- The role of the CRANKSHAFT is critical in the performance of our Honda engine.
- - The crankshaft converts the liner force from the expanding gases in the combustion chamber, into a rotational force along the crankshaft.
- o The offset lobes on the crankshaft allow a downward force to create a moment, or torque along the crankshafts axis.
- o The connecting rods attach the pistons to the crankshaft, and glide along bearings lubricated by oil in the crank case.
- o The four cylinder engine in our project has a piston being pushed down by expanding gases during every one of the four strokes in the engines cycle.
- o The synchronization of the crankshaft and the Honda’s dual over head camshafts is kept with chain sprocket on the end of the crank.
- o The weight of the piston/ connecting rod/ lobe combination would create significant vibrations if it wasn’t for the counterweights on the crank.
- - The CRANKSHAFT’s construction in our Honda engine is a cast alloy construction.
- The alloy crankshaft is made from a molten alloy, which is then vacuum-injected into a mold (to remove the possibility of air bubbles).
- The crankshaft is then machined to tight tolerances to ensure fitment, and longevity.
- The machined crankshaft is then high-speed balanced to ensure neutral balance at high rpm operation.
- o Cast steel alloys are strong, yet light- weight.
- o The cast method is easier to produce large quantities in-expensively.
- Pistons & Combustion Chamber:
- -The piston head is a metal cylinder
- -The purpose of the pistons are to power the crankshaft and to provide compression for the air/fuel mixture in the combustion chambers. The combustion process works via a 4-stroke cycle, also known as the Otto Cycle, which functions as thus:
- 1) Intake: The intake valve opens as the piston moves down, filling the chamber with a precisely calibrated air/fuel mixture
- 2) Compression: The piston then moves back up, compressing the mixture in order to amplify the power of the explosion
- 3) Power: The spark plug ignites causing the gasoline charge to explode, driving the piston down
- 4) Exhaust: As the piston reaches the bottom of its stroke the exhaust valve open to allow waste materials to be removed from the system
- -The connecting rod rotates at both ends so as to allow the angle to change smoothly as the piston and crankshaft move.
- -Piston rings are fitted into slots around the head which prevent gas leakage from the combustion chamber. Were we to ensure a previously working engine function again it would likely be necessary to replace the piston rings during assembly
- - Valves control the breathing of the engine. An air and fuel mixture is pulled into the engine when 2 of the fuel valves are open. The valves are closed off then the cylinder compresses the mixture and the spark plug ignites the mixture sending the piston downward, the exhaust valves are then opened to allow the exhaust from the ignition to escape as the piston pushes them out, this cycle then repeats. Thes valves are opened and closed by the camshafts.
- GearShift Drum:
- - The Gear shift drum is an important part of the Honda CBR600F2 engine. This drum gives the transmission the ability to shift gears. The drum looks like a cylinder with three different lines of groves cut into the side. There are three different forks that fit into these groves. These forks are also placed between gears of the transmission. With this set up, if the drum is turned it will shift the forks from side to side which in turn will change the gears within the transmission.
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- - The clutch is the part of the gear box that keeps the engine running as the driver changes gears. The clutch is made up of a series of plates held together under the compression force of four springs and works on the idea of friction. While driving, the clutch connects the crankshaft to the transmission and allows the crankshaft's energy to flow to the transmission, which in turn transfers that energy to the drive wheel. If the driver of the motorcycle pulls the left lever, the clutch will disengage. When pulling the lever, the wire connected will pull on the spring and separate the clutch plates. When the plates are apart, the crankshaft is disconnected from the transmission and no energy goes to the wheels. When the crankshaft is disconnected from the transmission the driver can shift gears. After shifting the gears, the driver would reengage the clutch, transferring the power again.
- - The Transmission is designed to let the motorcycle accelerate past t just what the engine would allow. The Transmission is basically a shaft of gears that can change, increasing the speed of rotation from the engine to final speed. The change of these gears can magnify the speed from the engine. When the transmission needs to change, the clutch is disengaged. When the clutch disengages all rotation to the gears stop. Once the gears have stopped spinning, the shift drum turns moving the folks. These folks shifted the gears into a different ratio. Then the clutch is reengaged in the new gear.
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- At this point, all components of the engine were disassembled down to their basic parts.
- CLUTCH ASSEMBLY:
- Friction disks and clutch seperation plates were placed around the clutch press plate.
- Clutch press plate was fitted into the outer clutch housing.
- Center clutch housing was fitted within the clutch disks and was secured using the clutch springs and lifter plate (cross shaped plate)
- Lifter plate was bolted to the press plate, securing the clutch.
- (Assembly was mostly done by hand. Socket wrench was used to fasten bolts to press plate.)
- Difficulty: Clutch Springs presented a problem, securing them with the lifter plate took more than one person.
- PISTON PLACEMENT AND CRANKSHAFT:
- Pistons were placed back on connecting rods, attached by the pins.
- (Assembly done by hand, clamp rings held pins in place.)
- Pistons were placed in the cylinder walls with the top of the piston facing outward from the crankcase.
- (A piston clamp made the piston rings hug the piston and the piston was pushed down into the cylinder using a rubber mallet.)
- Crankshaft was placed inside the crankcase with the gear end connected to the transmission.
- Connecting rods were fitted to the crankshaft, seperated only by the connecting rod bearings.
- Connecting rod tops were fastened to the rest of the rod with nuts and bolts, attaching the rods to the crankshaft.
- (Socket wrench was used to tighten nuts to bolts.)
- The piston head is cylindrical in shape.
- Difficulty: With the piston ring compressor (piston clamp), pistons went into cylinders nicely. Installing the crank shaft took many tries because of the gear end connecting to the transmission.
- CRANKCASE ASSEMBLY AND OIL PAN:
- Lower crankcase housing, containing transmission and crankshaft, was fastened to the upper housing with 10 flange bolts (in the body of the crankcase) and 16 sealing bolts (around the outer edge of the crankcase).
- Through the oil pan opening, the relief valve and oil strainer were placed back inside the crankcase.
- (Relief valve and strainer were installed by hand.)
- Oil pan was fastened to the bottom of the crankcase using 14 flange bolts.
- (A socket wrench was used to fasten the bolts.)
- Difficulty: With over 20 bolts being used to fasten the two housings together, this step was very time consuming. Not much trouble was encountered.
- CYLINDER HEAD ASSEMBLY:
- NOTE: Valves were ceased up inside head.
- Cylinder head assembly was set on top of the crank cse, covering the piston cylinders, with the cylinder head gasket between the head and crankcase.
- Cylinder head was fastened to the crank case with 10 socket bolts and 2 flange bolts.
- (A socket wrench was used to fasten the bolts.)
- Both camshafts were placed in the indentations provided by the head.
- Camshaft were secured in place with two covers, part of the cylinder head assembly, and with 10 flange bolts per cover.
- (A socket wrench was used to fasten the bolts of the camshaft covers.)
- Cam chain (timing chain) was placed around gear ends of camshafts and then placed around the sprocket of the crank shaft, connecting the cams to the crankshaft and transmission.
- Breather plate placed in clyinder head with flange bolts and cylinder head cover was fastened to the head with 6 specialty head cover bolts.
- A gasket was placed between the cylinder head and its cover.
- Difficulty: Difficulty was seen in synchronizing the camshafts and the crankshaft with the timing chain.
- COVERS AND EXTERNAL PARTS:
- Right crankcase cover (12 flange bolts) and alternator cover (9 flange bolts) were fastened to the engine.
- (A socket wrench was used to fasten the bolts.)
- Clutch lever and receiver were fastened to the right crank case cover.
- Water pump was fastened to crank case with 2 long flange bolts.
- Difficulty: Easy to install covers and waterpump. Since they were external parts, they were installed last.
- NOTE: Carburetor consisted of 4 identical assemblies. Only one was disassembled and reassembled.
- Float was placed in the chamber set and sealed with a gasket and upper carburetor housing. Specialty screw set fastened the two parts together.
- (A screw driver was used to fasten the two main carburetor parts together.)
- Vacuum piston was placed in the upper side of the carburetor.
- A spring was inserted into the vacuum piston, around the jet needle.
- The carburetor top was fastened over the vacuum piston, securing the spring, with a pan screw.
- (A screw driver was used to fasten pan screw.)
- Carburetor assembly, containg all for carb. components, was fitted to the side of the cylinder head (the side with the 4 carb. insulators and ring fasteners).
- (A rubber mallet was used to push the carburetor onto the cylinder head and a phillips head screw driver tightened the ring fasteners.)
- Difficulty: Reassembling the carb component was easy. Very difficult to connect the one carb component to the rest.
- AIR CLEANER:
- Air cleaner base, containing 4 air funnels was fastened to the carburetor assembly with 16 screws/washers.
- Lower air cleaner assembly was fastened to the base with 6 screws.
- Air cleaner element (filter) placed inside housing and the air cleaner cover was fitted over that, with 6 screws.
- (A phillips head screw driver was used to fasten the screws.)
- Difficulty: Included connecting the two housings to the base, done quickly and easily.
While even a small engine such as this has many parts and components, the functionality of the engine is fairly straight forward. After we opened up the engine, we learned that it works as follows:
- Fuel enters the carburetor where it is combined with air so that it will be optimally combustible.
- The fuel is then sent into the combustion chambers by means of the cams, which are kept in perfect time with the pistons.
- Combustion of the fuel/air mixture drives the pistons, which in turn rotate the drive shaft.
- The drive shaft has the duel purpose of keeping the cam shaft in time, and transferring its rotational energy to the transmission.
- The transmission changes the angular velocity of the rotation, depending on the velocity of the motorcycle. It then transfers that energy to the drive wheel, which powers the motorcycle.
- The clutch is manually operated and separates the transmission from the drive shaft so that the gears can be changed, which will change the energy sent to the drive wheel.
- Total Recorded Number of Parts (including fasteners): 345
Unfortunately, the engine would not have worked when we received it. We had no fuel, and several parts were damaged or missing. However, after reassembly we were able to see what was missing, and make a few adjustments so that the parts fit together more like they were supposed to. We were also able to drive the parts by hand and get them to work in sync with each other.
In order to analyze this engine, or its parts, very precise models would be needed. All the parts in this engine work together in unison, and altering any part of them can seriously hinder their performance. For this reason, models of the engine would either need to be very exact prototypes, or precise computer simulations. The knowledge of sizing of parts, locations, and even fuel mixtures need to be very precise because if they are not, the engine might not work. Furthermore, estimates can be dangerous because this is a tool designed to carry a person from place to place, and short cuts can not be taken when the safety of another person is on the line.
The disassembly process for this engine was completely reversible. In fact, we discovered on reassembly that there was only one order we could put the engine back together in. The first day we wanted to put the engine back together, one of the pistons was still at the home of a team member being modeled on the computer. Because of this we could not reattach the crankshaft. We needed the inner parts together so that we could put the engine block back together. After that, each part went back together in order; the cams, then the camshaft, then the carburetor and air filter.
The reassembly also required considerably greater delicacy as we had to make sure all the parts were inserted so as to preserve the exact operational timing. For example, the gear ends of the cam shafts have a marker on them that indicates what directions they need to be in when the chain goes around them. If they aren't connected in the right way with the chain, they will fail to rotate in unison and therefore the valves won't open and close at the precise time that they're supposed to, rendering the entire engine inoperable.
The most significant design change at the component level that we would suggest is standardization. The most used tool in the assembly/disassembly of this engine is a socket wrench, but there are many different sized bolt heads, so different sized sockets were needed. It is understandable that bolts will be different lengths and sizes because they connect different parts, some of which need to be more secure than others. However, if all the bolts had the same sized head, it would be much easier to get inside the engine block and perform repairs.
At the product level it is difficult to suggest many changes because this is a good, efficient engine that is only a little more than ten years old. Without making any significant alterations to the actual types of parts that this engine has, the best update possible would be materials. As lighter, stronger, and more wear resistant metal alloys and plastics are developed, they could replace some of the old aluminum and steel parts to reduce weight and friction in the engine, while increasing durability and functionality. This would be especially useful for parts such as the pistons, transmission, and clutch, which undergo a lot of strain and need to maintain high functionality. Also, a lighter weight engine would, in turn, increase fuel efficiency. One modification that could be done immediately to increase performance would be to add a turbo or supercharger. These are essentially air compressors that pump more oxygen into the fuel mixture to increase horsepower.
Another major suggestion for the manufacturer of this engine deals with environmental sustainability. Motorcycles are already very fuel efficient machines because they are light weight. However, given the recent gas crises and the push to make all vehicles more fuel efficient, new technology could be used to make this engine more environmentally friendly. A motorcycle that uses alternative fuel sources such as Bio-diesel, ethanol, electricity, or even uses hydrogen fuel cells would have extremely low emissions. This would be very popular among riders who are conscious of their impact on the world.
Wahlster, K. (2008). 1994 Honda CBR600F2. Retrieved from Bke Bandit: http://www.bikebandit.com/houseofmotorcycles/honda-motorcycle-cbr600f2-1994/o/m2043