Racr Sequence - iBike Gen III Operating Instructions Manual

RACR SEQUENCE

The Racr (racer) sequence contains settings of interest to advanced power meter users and
bike racers.
To access the RACR sequence, enter Setup then scroll to RACR. If the screen says RACR
YES then click up arrow button to enter the sequence; if the screen says RACR NO, then
click the center button, select YES with the up arrow, then click the center button to
accept. Then, click the up arrow to enter the RACR sequence. Here are the steps included
in the RACR sequence:
"RACR YES", then click up/left arrow successively to perform:
Estimate frictional drag: "EST FRIC"
•
Display TSS/IF/NP measurements in the Totals screen: "TSS"
•
Configure Functional Threshold Power: "FTP CFG"
•
Display CdA data on screen (NOTE: iAero feature ONLY): "CdA"
•
Set total hours logged: "TOTAL HRS LOG"
•
Turn cadence display On/Off: "Cad On"
•
Set total distance logged: "TOTAL ODO"
•
Each of these settings is explained below:
"EST FRIC" (estimate Frictional drag)
•
Bikes have an intrinsic level of rolling resistance (frictional drag) that is dependent on tire
type, tire pressure, and road surface. This factor is called "Crr" (coefficient of rolling
resistance) and Crr is a number generally between 0.003 and 0.008. The higher the Crr
the higher the rolling resistance.
For example, with normal bike tires a very smooth velodrome track will have a Crr of about
0.003; asphalt will have a Crr of about 0.0055, and dirt roads will have a Crr of 0.008 or
higher.
The iBike's coast down process can measure Crr (in addition to CdA, the aerodynamic
resistance) but in many cases it's easier and faster just to assume a value for Crr.
Assuming a value of Crr can improve the accuracy of the CdA measurement.
The default setting for EST FRIC is YES; that is, in the EST FRIC YES setting the iBike will
assume a fixed, user-set value of Crr, even when coast downs are performed.
The default value of Crr has been set at the factory to 0.0055; on the iBike, this reads as
"55" in the screen. The value of Crr can be set by the user.
To use the estimated Crr feature do the following:
1) Go to Setup/RACR YES/EST FRIC.
2) Click the center button; the bottom screen flashes. Use the up arrow to select YES,
then click the center button to accept. "done" flashes
3) The screen FRIC appears; the number at the bottom is the value of Crr currently
stored in the iBike.
4) To change the value of Crr (fric) click the center button. Adjust the digits to the
value you want. Fric = 30 corresponds to a very smooth velodrome; 55 is an
average asphalt road; 80 is rough concrete; 100 or higher is dirt roads. These
values are approximate; you can get more exact values from the web.
5) When you've entered the value you want, click the center button to accept. Done
flashes and the iBike proceeds to the next RACR screen, TSS
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