Speed can be useful in both km/h, the Split field .SpeedOrPace will return the speed or pace for a split or leg according to the default unit for the type of sport and the units of measurement in the Event file, it also returns the unit as part of the field. 

This file is set to use Metric units so all cycling speed is returned as km/h. 

To get the speed for bike lap 7, we need to use the BikeFinish sector, since BikeFinish.SpeedOrPace would return the average speed from the start, we therefore use BikeFinish.Sector.SpeedOrPace for km/h. 

To calculate speed in mph we can use speed(), this uses 3 parameters, time, distance and unit of distance. 

Our time will use BikeFinish.Sector

For the distance we can call the sector distance, by default this is returned as a value in meters, but we can also call this in miles using BikeFinish.Sector.Distance.Miles.

Our Speed() function uses each of these and the unit as "miles".

Speed([BikeFinish.Sector.Decimal];[BikeFinish.Sector.Distance.miles];"miles")

Note:  In versions of RACE RESULT up to 12.1.2 there is an error with the speed calculation in miles, where the value is wrong by a factor of 1000 so may require additional calculation to return the correct speed value. 

We additionally have to append the unit of speed as text to this, since this is just a numerical value.