Hong Kong Regulations

ROAD TRAFFIC (CONSTRUCTION AND MAINTENANCE OF VEHICLES) REGULATIONS - REGULATION 20

Wheels and tracks

(1) Every motor vehicle and every trailer shall be so constructed that the
entire weight of the vehicle and of any trailer attached thereto is
transmitted to the road surface by wheels or by tracks, or by a combination of
wheels and tracks.

(2) In the case of a track laying vehicle-

   (a)  the parts of the track which come into contact with the road surface
        shall be flat and have a minimum width of 15 millimetres; and

   (b)  the total area of each track actually in contact with the road surface
        at any one time shall not be less than 230 square centimetres in
        respect of each tonne of the gross vehicle weight of the vehicle.

(3) Subject to paragraphs (6) and (7), every wheel of a motor vehicle, other
than a road roller, and every wheel on a trailer when the trailer is being
towed on a road, other than a trailer used solely on road repair work, shall
be equipped with pneumatic tyres of suitable size and design.

(4) Subject to paragraph (8), all wheels of a motor vehicle or trailer which
are equipped with tyres, other than pneumatic tyres, shall have a rim diameter
of not less than 700 millimetres.

(5) Every wheel of a vehicle shall be truly circular, accurately centred on
its axle and fitted to work thereon without oscillation or side play.

(6) The Commissioner by permit in writing, subject to such terms and
conditions and for such period as appears to him fit, may authorize the use of
a motor vehicle which does not comply with paragraph (3).

(7) Paragraph (3) shall not apply to-

   (a)  a motor tractor; and

   (b)  a motor vehicle designed for use in works or on private premises and
        used on a road only in passing from one part of the works or premises
        to another or to works or premises in the immediate neighbourhood, if
        such vehicle is equipped with tyres on every wheel of soft or elastic
        material of a design and type approved by the Commissioner.

(8) Paragraph (4) shall not apply to-

   (a)  any motor vehicle or trailer not exceeding 1.5 tonnes unladen  weight
        designed for use in works or on private premises and used on a road
        only in passing from one part of the works or premises to another or
        to works or premises in the immediate neighbourhood; and

   (b)  any mobile crane.