<P> A close - ratio transmission is a transmission in which there is a relatively little difference between the gear ratios of the gears . For example, a transmission with an engine shaft to drive shaft ratio of 4: 1 in first gear and 2: 1 in second gear would be considered wide - ratio when compared to another transmission with a ratio of 4: 1 in first and 3: 1 in second . This is because the close - ratio transmission has less of a progression between gears . For the wide - ratio transmission, the first gear ratio is 4: 1 or 4, and in second gear it is 2: 1 or 2, so the progression is equal to 4 / 2 = 2 (or 200%). For the close - ratio transmission, first gear has a 4: 1 ratio or 4, and second gear has a ratio of 3: 1 or 3, so the progression between gears is 4 / 3, or 133% . Since 133% is less than 200%, the transmission with the smaller progression between gears is considered close - ratio . However, the difference between a close - ratio and wide - ratio transmission is subjective and relative . </P> <P> Close - ratio transmissions are generally offered in sports cars, sport bikes, and especially in race vehicles, where the engine is tuned for maximum power in a narrow range of operating speeds, and the driver or rider can be expected to shift often to keep the engine in its power band . </P> <P> Factory 4 - speed or 5 - speed transmission ratios generally have a greater difference between gear ratios and tend to be effective for ordinary driving and moderate performance use . Wider gaps between ratios allow a higher 1st gear ratio for better manners in traffic, but cause engine speed to decrease more when shifting . Narrowing the gaps will increase acceleration at speed, and potentially improve top speed under certain conditions, but acceleration from a stopped position and operation in daily driving will suffer . </P> <P> Range is the torque multiplication difference between 1st and 4th gears; wider - ratio gear - sets have more, typically between 2.8 and 3.2 . This is the single most important determinant of low - speed acceleration from stopped . </P>

For a simple gear train velocity ratio is the ratio of