How Does A Tyre Pressure Monitor Work

As the number of motorcyclists increases, more safety systems have been gradually been added to motorcycles. In recent times, tyre pressure monitoring systems have been increasingly common as an OEM feature. However, if your motorcycle does not have one equipped, fret not, as there are aftermarket options that can be retrofitted!

Being able to know your tyre pressure levels can save you from a lot of headache and possibly even from an accident!

Let’s take a look at the available TPMS options.

External TPMS

Credit: HardBagger

External or Indirect tyre pressure monitors are mounted on the valves, replacing existing valve caps. However, these sensors do not directly measure the pressure of the tyre. Instead, these sensors are actually detecting the rotational speed of the tyres. As the tyre pressure drops, the diameter of the tyre reduces, thus increasing its rotational speed. The sensor will detect this difference in rotational speed, and provide an estimated pressure drop readout to the display module.

  • Pros

Easy installation – Directly replace existing valve caps
Lower Cost compared to Internal TPMS

  • Cons

Does not directly measure tyre pressure
Requires proper calibration to match tyre size

Internal TPMS

Credit: CarBikeTech

Internal or Direct tyre pressure monitors are installed on the wheel itself, replacing the existing valve stem. These sensors will read the actual tyre pressure of each individual tyre and send the readout to the display module.

  • Pros

More accurate pressure reading
Longer lasting batteries

  • Cons

Requires removal of tyres for installation
More expensive compared to External TPMS


Even though a tyre pressure monitoring system is a handy tool to have, there can be inaccuracies when they are not calibrated properly. It is still a good practice to manually check your tyre pressures occasionally.

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