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In order to improve the performance and fuel economy of a reciprocating engine, it is important to reduce the overall engine frictional losses. In this paper, author conducts an experimental study on the friction characteristics due to pumping loss, valve-train system, piston assembly, auxiliaries and transmission for a 110cc, single cylinder 4-stroke gasoline engine using frictional strip-down analysis. Friction strip-down method is commonly used to investigate the frictional contribution of various engine elements at high speeds and for better understanding of the make-up of the total engine friction. The engine friction measurements for the particular engine are carried out on a motoring test rig at different engine speeds. In addition, the effect of engine operating parameters such as oil temperature and oil quantity in engine sump is also presented in detail.

The customer needs and expectations in the automotive industry have become more demanding in recent past. This puts huge pressure on new product development (NPD) cycle as well as timelines on the automotive OEMs. The design verification and proving falls at the end of any NPD cycle and consumes significant amount of time. The major constituents of design verification and proving phase are the accelerated life tests conducted at a laboratory scale. These tests need to be correlated to the field usage condition in a correct and precise way in order to shorten the time spent in design iterations. This paper discusses on arriving at a correlation between field usage and one of the laboratory scale accelerated life tests for a small four stroke two wheeled vehicle engine through lubrication oil analysis technique. The lubrication oil used in different customer engines is collected from field and analyzed.

This work shows numerous experimental and simulation results regarding the stability of a three-wheeled vehicle. Some vibration modes concerning three-wheeled vehicles can become unstable for a given vehicle speed. In particular, the wobble mode involves mostly the front frame while the weave mode involves mostly roll and yaw oscillations of the rear frame. This paper mainly focuses on the wobble mode, which was identified as the most influential vibration mode impacting vehicle handling, through experiments on the road using the three-wheeled passenger vehicle. A large number of parameters such as caster trail, steering damping coefficient, front frame inertia about steering axis, front tire characteristics and chassis stiffness influence the wobble vibration mode. This work mainly focused on steering damping coefficient and caster trail, and its effect on wobbling stability.

A methodology is presented to obtain loads coming on the handle bar of a motorcycle of one model and calculating generic loads from the same for all other motorcycle models. The handle bar of a motorcycle of model M1 was instrumented with strain gages and calibrated for vertical and horizontal loads. The instrumented handle bar was assembled on the vehicle and data was collected on the test rig in laboratory. The vertical and horizontal loads acting on the handle bar, on test rig was obtained based on the calibration performed. The loads thus obtained are for a particular motorcycle model M1 and is dependent on the wheel loads of that motorcycle. These loads were converted into generic load cases, which are applicable for all models of motorcycles. The generalized loads thus generated were used in predicting the fatigue life of handle bar of a different motorcycle model (M2) using FE analysis and MSC fatigue.

In the recent years, reduction of new product development time is the major challenge for all auto manufacturers to sustain in the stiff competition. Durability evaluation is one of the most time consuming element in New Product Development (NPD) process. Finding a generic solution for commonly faced design issues is a key factor for dramatic reduction in evaluation time. Testing time reduction can be achieved by breaking down the evaluation into subsystem level and component level instead of complete vehicle. But the maximum time reduction can be achieved only through durability evaluation at material / process level. This type of evaluation yields a generic solution, which results in establishing all-purpose design and material selection criteria during initial stage of development. By adopting this technique, separate evaluation of vehicles/ subsystems for improvements in material, welding, process etc. can be avoided.