Table of Contents
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M
MAP Sensor
Manifold Absolute Pressure Sensor.
Main Bearings
The bearings between the crankshaft and the engine case 1)
Magneto Ignition System
Micrometer
A precision instrument used to measure outside diameters of parts
Microwelding
Adherence of sporadic particles of aluminum from the piston to the bottom side of the piston ring. 2)
Monograde Oil
Oil with a single viscosity, i.e. SAE80W. AKA Straight Oil
Multigrade Oil
Motor or gear oil that has a wide viscosity range (meeting the requirements of more than one SAE viscosity grade) and thus it can be used in a wider temperature range., i.e. 10W50. The “W” stands for Winter therefore 10W50 oil has a viscosity range from SAE10 when cold to SAE50 when hot. 3)4)
Multimeter
A testing instrument for most electrical things on a motorcycle. There are variations in makes and models but most come with the ability to check for voltage, continuity and resistance (Ohms). Some do not have a buzzer to sound off when continuity is broken but this is a very important feature to have.
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