Operation Manual

7 | P a g e
4 Product Description of FOBO Bike
4.1 Tire Sensor Unit
Knob cover - waterproof cover. Please ensure the red silicon ring is
intact to prevent water from getting into electronics
compartment.
Single internal battery - CR2032 coin cell battery. When replacing battery, please
ensure the +” sign of the battery is facing up, away from
PCB.
Internal PCB - internal electronics circuit (The pressure sensor chip is
mounted within this PCBA, and it senses the tire pressure
against a built-in vacuum, resulting in an Absolute
Pressure reading. The internal firmware will then subtract
the sea-level pressure of 101.3 Kpa (14.7 psi) from this
reading. This final reading which will be shown in the app
can be termed as i) Tire Absolute Pressure minus sea
level pressure, or ii) Gage Pressure reference to sea-level
altitude. With this formulation, Fobo Bike sensor will read
the same pressure value for any given tire, irrespective of
altitude (assuming a constant temperature). This will
ensure the correct tire footprint per vehicle manufacturer‟s
pressure recommendation, for all altitude above sea-level,
given a constant temperature.