Bowmonk Brakemeter / Dynometer


Replaces the Tapley Meter
Hand-made precision instrument
Windscreen suction cup
Measures deceleration & acceleration
Easy to use
For Vehicle Classes 3, 4, 5 & 7


The Brakemeter / Dynometer is a hand-made precision instrument that mechanically measures both deceleration and acceleration. The instrument consists of a finely balanced pendulum, free to respond to any changes in speed or angle, working through a quadrant gear train to rotate a needle round the dial. The dial is black with silver white graduations and has a linear length of 5 1/2 inches (114 mm). The unit is filled with a special fluid which damps out all vibration. Other than a calibration every 2 years, which is carried out by Bowmonk, no maintenance is necessary.

The dial is calibrated in percentage “G”, the accepted standard throughout the world for measuring acceleration and deceleration. There are no connections to the vehicle other than mounting – either with two self-tapping screws onto a heavy stand or by using the suction cup operated by the small side lever.

In the UK, Bowmonk brake meters are approved by the DVSA for use in the annual MOT vehicle-testing scheme. Wherever brake testing is mandatory by law the Bowmonk Brakemeter/Dynometer is an approved brake test instrument and we recalibrate and repair the Brakemeter/Dynometer, the Tapley meter, and our newer electronic decelerometers.

Test Procedure

Test the vehicle on reasonably level road. The meter is set to zero by releasing the thumbnut, tilting the bowl in its pivots until the main needle points to zero and re-tightening the thumbnut. The meter is now ready for use. It is not necessary to watch the instrument continuously as it is fitted with a recording needle. Depending on the test to be performed the recording needle is positioned to left or right of the main needle by turning the centre chrome knob, and will accurately record the maximum deceleration/acceleration reading.

Part Codes

BOW001 – Bowmonk Brakemeter / Dynometer (Mk III)
Mechanical instrument for measuring deceleration and acceleration.

BOW002 – Stand for Brakemeter
A heavy base to which the BOW001 Brakemeter can be secured, if not using the built-in suction cup.

BOW003 – Kit (Brakemeter & Stand)
This part code can be used to order parts BOW001 and BOW002 together.

BOW004 – Wooden carry case for Brakemeter & Stand
A sturdy wooden carry case which accommodates both the BOW001 Brakemeter and the BOW002 stand.

BOW005 – Complete Kit (Brakemeter, Stand & Carry Case)
This part code can be used to order parts BOW001, BOW002 and BOW004 together.

Brakemeter / Dynometer PDF Datasheet