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Behavior of particle emission from small non-road engines is still unknown which may have some unavoidable health risk. Investigation of particle emission from small non-road engine has made the main objective in this study. For this purpose a particle counting system has been developed according to the PMP protocol. The investigation was limited to only number counting of solid and volatile particle emission from a small diesel powered electric generator set. Especially the relative emission of solid and volatile particles for different load conditions has been investigated. Measurement was attempted by controlling the dilution air temperature and temperature of an evaporation unit installed inside the particle counting system. It was found that the small diesel engine used in the generator set emits huge number of volatile particles depending on operating condition.

The performance and emissions of an engine can be improved by accelerating the mixing process. This can be achieved by secondary atomization (micro explosion) and hot (ceramic coated) combustion chamber. An attempt was made to study the effect of water diesel emulsion on a ceramic coated [plasma sprayed zirconia (PSZ) coated cylinder head and valve faces] diesel engine. 5% decrease in brake specific fuel consumption (BSFC) for 10 volume percent of water in the case of conventional engine and a 21% decrease in BSFC for 18 volume percent of water in water diesel emulsion in the case of partially ceramic coated engine (BSFC, for 15 and 18 volume percent of water in emulsion, being same) was obtained compared to conventional engine fueled with neat diesel at 100% load. Hence, ceramic-coated engine permits use of 8% more water in water-diesel emulsion. Partially ceramic coated diesel engine for neat diesel has shown marginal decrease in BSFC at higher loads and no change at lower loads.

Because of its low coefficient of friction, DLC(Diamond Like Carbon)-coating is recognized as one of the effective ways to reduce machine friction. On the other hand, sliding smoothness of motorcycle's front fork is requested to progress, therefore reducing friction of front fork is significant. From our considering whether DLC coated inner tube would be a good idea to reduce friction of front fork, we decide to build the mass-production process for the DLC coated inner tube. But there are two issues about the function of the DLC film, those are “how to improve resistance against peeling” and “how to get well-flattened DLC surface”.

In research conducted at Brigham Young University, four coatings were tested for their ability to increase the wear life of primary clutch sheaves made of A390 die-cast aluminum used in continuously variable transmissions (CVT). The coatings tested were: hard chrome, electroless nickel metal, hard coat anodizing and composite ceramic coating. A wear test stand was developed to duplicate wear found on CVTs currently in use. The wear was evaluated using four methods. The test first method characterized the shift delay properties of the worn CVTs while running on the wear test stand. As the CVT was run on the wear test stand a delay in shifting would develop during the unloading cycles. The second method used an ATV and chassis dynamometer to evaluate the change in performance with wear. The third method used a profilometer to evaluate the amount of material lost, through wear.

In an attempt to grab potential issues with a hydrogen direct injection lean burn engine to have similar power output to a gasoline-fuelled engine, emission characteristics of a hydrogen engine was investigated. It is demonstrated that low NOx emission can be achievable without any catalytic converter. Two major issues, however, have been recognized, that is, combustion instability at low load conditions and too low temperature of exhaust gas to get enough boosting pressure. Hydrogen concentration heterogeneous of the mixture was focused in the CFD and visualization study. Hydrogen jet design of an injector could contribute to improvement of mixing.

Using blends of natural gas (NG) and hydrogen as an alternative to gasoline in Internal Combustion Engines (ICEs) has the potential of a major reduction in CO2 and other harmful emissions, besides giving insight into the use of gaseous biofuels, rich in methane and hydrogen, and offering a transition scenario towards a hydrogen economy. To investigate the consequences of using blends, the performance of a 240cc stationary ICE and a Yamaha Majesty YP125FI scooter, converted to run on a large variety of blends of hydrogen and NG, have been investigated at HAN University, Netherlands. The effect of the air-to-fuel ratio and the composition of the blend on the performance and the emissions have been studied. This paper gives insight into those effects. Main conclusions: With only minor modifications a large variety of blends can be used.

Several engine manufacturers are offering 4-stroke marine engines in order to meet 1998 US EPA emissions regulations requiring a 75% hydrocarbon reduction by 2006. These 4-stroke marine engines have been lubricated with passenger car motor oil in the past; however, the environment in which these engines operate is quite different from a passenger car engine. Perhaps the biggest differences are that marine engines do not use a closed loop cooling system, and they often operate in a corrosive salt water environment. They may be operated for extended periods of time at low speed while trolling, allowing build-up of water and fuel in the engine oil. For these reasons, oil used in this application should have corrosion inhibiting properties that are much better than what is found in passenger car oil. In addition, boats are often used seasonally and stored for long periods of time during the winter.

In manufacturing, the term “processing” refers to the various processes for changing the dimensions, shape and qualities of a material to fit the required specifications for use in a product. One processing method is machining, which involves cutting away portions of the material to achieve the desired dimensions and shape. This machining method has some inherent demerits, such as the fact that it naturally produces chips etc., depending on the material involved, which end up as waste and are thus environmentally undesirable. Another disadvantage is that machining often involves a longer processing time, which increases cost. In an ideal form of “product creation,” the material forming and fabrication process would produce the net shape of the product without a need for machining, and thus reduce cost and eliminate the waste of chips. The plastic (plasticity) forming method is an alternative to machining that makes it possible to achieve a more ideal form of manufacturing.

With environmental issues at the forefront of the automotive industries, there is a clear need to improve the fuel economy and longer drain performance of four-cycle motorcycle engine oils. Evaluation of oil consumption in actual engines was used to clarify an optimal volatility for engine oils, and the feasibility of using zinc dialkyl phosphate, a sulfur-free additive, as an alternative to ZDTP for improved of fuel economy performance was studied. Engine oils with optimized additives demonstrated excellent friction characteristics and wet clutch performance.

The computer simulation on motorcycle crashworthiness has been introduced to develop and evaluate a new airbag system for motorcycle. We chose MADYMO (multi-body dynamics) and PAM-SAFE (finite element method) for the basic simulation software. In addition to using these computer simulation tools, several full-scale tests were performed. This new airbag system has some features that are newly developed for motorcycle. This system has been shown to be promising by some simulations and tests. However there are still many technical issues to be investigated and solved in order to put the system to practical use. One of the most important issues is to investigate the effectiveness of the system in various collision configurations. (ISO13232, which stipulates research evaluation methods for motorcycle rider protective devices, requires 200 configurations of collision simulation for evaluating risk/benefit factors.)

The further optimization of modern gasoline engines needs sophisticated development tools to meet future emission legislation and fuel consumption targets. The multi-dimensional optimization process has to take into account parameters like Cylinder head and port flow design Valve train variabilities (e.g. camphasers, variable valve lift systems) In-cylinder charge motion and interaction with mixture preparation Resulting combustion characteristics Naturally aspirated and boosted operating conditions The paper presents an advanced development process, where a dedicated interaction between Gas dynamics and CFD simulation, Optical analysis tools (3D-PIV) and Engine test bench is used. Simulation approaches are typically used during the first concept and following design phase. Due to the complexity of simulation models and the need for a detailed validation, advanced optical analysis tools need to be integrated in the development process.

Tyres are the primary contact between the vehicle and the road. It serves as the medium of communication between the road and the rider, which it does in terms of road loads and displacements. Therefore, measurement of dynamic wheel forces experienced by a two-wheeler is crucial for tuning the ride and handling characteristics of the vehicle. Currently, there are standard wheel force transducers available in the market, which are extensively used in cars. However, mass of such a system is relatively high to be used on two-wheelers. Special wheels and adaptors increase the unsprung mass considerably, which changes the dynamics of the vehicle. Moreover, cost of such systems is exorbitantly high to be used for two-wheelers. This paper describes the development of an innovative and a highly versatile and low-cost alternative method for real-time measurement of dynamic wheel loads and moments of a two-wheeler when compared with the currently available systems in the market.

This paper aims at the estimation of dynamic wheel loads of a two-wheeler through mathematical modeling that will aid during the initial stages of product development. A half car model that represents a two-wheeler was used for this purpose. Road displacements were given as input to the model and the wheel loads estimated. Actual road data obtained from two-poster rig was used as input to the model thereby making it possible to calculate the wheel loads for different customer usage conditions on different roads. In this paper, a severe rough road was chosen for verification of the model with that of the rig as the rider dynamics on such roads are the most difficult to simulate even on the rigs. The estimated values from model were verified with those measured using a two-poster rig for the same road displacement. Attempt has been further made to establish a correlation between the ride comfort predictions from the model and the two-poster rig.

For a disaster relief and automatic inspections, an unmanned helicopter is strongly expected. To develop this, a very high power density source is required. A Wankel-type rotary engine can be the best candidate for the power source. In this study, the development of a very small rotary engine with a displacement of 30 cc is targeted. In order to improve the combustion efficiency, gas exchange and stable ignition, a multi dimensional simulation inside the combustion chamber was carried out. At first, the effect of volumetric efficiency on the maximum power is mentioned. Secondly, the effect of scavenging efficiency is discussed. Thirdly, a blow off through a plug hole is described. The position of plug hole was found important to reduce the blow off amount. Finally, the effect of combustion speed on the engine performance is predicted. As a result, the proposed design will be tested using a proto-type engine.

This paper reports the new design method of vibration isolation mount for the scooter powerunit. In the conventional design, while the engine vibration is efficiently isolated by the link mechanism, the time lag induced by the movement of the link mechanism spoils the riding quality when the rider operates the steering or the throttle. To solve the problem, a new design without the link mechanism was proposed. The optimized combination of the crank balance and the single-axis balancer was used to control the orbit of the powerunit vibration. First, the new equations were introduced to balance the inertial forces and moments at the target position by optimizing the amount and the phase of the crank balance and the balancer. Then, some results from the experimental tests were reported to validate the numerically optimized design. Using this new design method, the riding pleasure can be enhanced without unpleasant mechanical vibration.

Motorcycle configurations, such as CG (center of gravity) location, have come to be fixed to the current ones by trial and error since motorcycle was born. Generally motorcycles' ratio of CG height to wheelbase is relatively higher than four-wheel cars'. We have analyzed the optimal motorcycle CG location with relatively simple formulas, which we have derived to calculate the maximum acceleration with three performance limitations and calculate the maximum speed and the shortest time to run through a course. The results show that the calculated speed is significantly close to actual sport motorcycle's and that the optimal CG locations for various courses are bounded in a certain limited area which is near actual sport motorcycle's.

The Formula SAE (FSAE) rules require mounting an impact attenuator (IA) to the front part of the formula car. The IA is necessary to take fully into account not only lighter weight of the parts but also cost effectiveness as the total cost and the workability of manufacturing have much value to win the FSAE. In this paper, three different IAs, 1) a space frame structure with steel pipes (SSF), 2) a monocoque structure with aluminum (AM) and 3) a monocoque structure with Carbon Fiber Reinforced Plastic (CFRPM), were manufactured and compared with respect to the weight and the cost effectiveness under FSAE rules. The FEM simulations for the AM were performed and the calculated results showed good agreements with the experimental ones. However, the AM could not absorb the impact energy experimentally. The CFRPM could absorb the required impact energy with lighter structure compared to other IAs. The weight was half of the experimental SSF and 1/5 of the calculated AM.

Future exhaust emission targets and increasing customer demands call for the implementation of enhanced engine technologies, as well known from automotive applications, into small capacity engine categories. Especially the applied engineering solutions in the market of motor vehicles driven by engines up to 50 cm3 displacement have been significantly changed in the last years. Beside low cost technologies (air cooled two stroke or four stroke engines with carburetor), enhanced mixture preparation and exhaust gas after treatment systems come to use. Highly technological two stroke engines are equipped with direct fuel injection systems in combination with efficient exhaust gas after treatment methods; in four stroke engine applications intake port fuel injection systems in combination with oxidation catalysts or 3-way catalytic conversion are established on the market.

In recent years, exhaust emissions regulations is increasingly enhanced on the non-road diesel engines, which are mainly used for agriculture, industrial and construction applications in world-wide area, in order to prevent air pollution on the earth. On the other hand, customers demand higher power in a tight packaging constraint to be competitive on the product that the engine is installed. We developed the all-new 1.3 liter non-road In-Direct Injection (IDI) diesel engine, which realized to balance the strict exhaust emissions regulations and user needs such as compact and higher power. This paper reviews the technologies to achieve the targets, higher power density and lower exhaust emissions on the newly-developed small IDI diesel engines.

Small off-road engines (SORE) have been recognised as a major source of air pollution. It is estimated that non handheld SORE annually produce over 1 million tonnes of HC+NOx and over 50 million tonnes of CO2. The fuel system design and its operating AFR are of key importance with regard to engine operation and engine out emissions. The conventional low-cost float carburettors used in these engines are relatively ineffective at atomising and preparing the fuel for combustion requiring a rich setting for acceptable functional performance. EPA and CARB have confirmed that Phase 3 limits are achievable for a “durable” engine fitted with a conventional well calibrated and manufactured “stock rich setting” float carburettor together with catalytic oxidation after-treatment and passive secondary air injection.