Usually by having a special rear hub which measures the output of the rider.
Both of them are for measurements of types of energy. kWh is the full measure of energy while kW is the measure of power.
To accurately measure the width of a bicycle rim, use a caliper or ruler to measure the distance between the inner edges of the rim where the tire sits. This measurement will give you the width of the bicycle rim.
To measure a bicycle tube size accurately, first remove the tube from the tire. Then measure the diameter of the tube and the width of the tire. Use these measurements to determine the correct tube size for your bicycle.
To accurately measure the height of a bicycle, use a tape measure to determine the distance from the ground to the highest point of the bike's frame, typically the top tube or seat tube. This measurement will give you the overall height of the bicycle.
To accurately measure the size of a bicycle wheel, use a tape measure to determine the diameter of the wheel from one edge of the tire to the other. Make sure to measure from the center of the wheel for accuracy. The size of a bicycle wheel is typically expressed in inches or millimeters.
Kilograms.
To measure the frame size of a bicycle accurately, use a measuring tape to measure the distance from the center of the bottom bracket to the top of the seat tube. This measurement is typically in inches or centimeters and represents the frame size of the bicycle.
To measure bicycle handlebars accurately, use a tape measure to determine the width between the two ends of the handlebars. Measure from the center of one end to the center of the other end for an accurate measurement.
To measure bicycle tires accurately, use a tape measure to determine the diameter of the tire from one edge to the other, passing through the center of the tire. This measurement is typically in inches or millimeters and can help you determine the correct tire size for your bicycle.
To accurately measure chainline on your bicycle, you can use a ruler or measuring tape to measure the distance between the center of the seat tube and the center of the chainring. This measurement will give you the chainline of your bike.
To measure bicycle stem length, first remove the handlebars and measure the distance from the center of the handlebar clamp to the center of the steerer tube. This measurement will give you the accurate length of the bicycle stem.
To measure bicycle wheels accurately, use a tape measure to determine the diameter of the wheel from one edge of the tire to the other. Make sure to measure from the center of the wheel for accuracy. This measurement is typically expressed in inches or millimeters.