Wheel Types 10 to 14 – 5 Stud QD Rear, 1950-58, All Frame Types

After a break of 10 years a QD wheel was available again, similar in design to the earlier 3 stud design but with 5 studs and no pegs this time round. Initially offered as an option, it was standard fitment on Square Fours and is therefore frequently referred to, incorrectly, as a ‘SQ4 back wheel’.

Dangerous downward pointing brake arms – What is the problem and what can be done about it? Only bikes with plunger frames and brake arms that point downwards are affected, originally those produced between 1953 and 1954. The first time that many owners realize that there is a problem is when the rear wheel locks up causing the bike to skid to a halt or worse. This will happen when the rear brake is applied reasonably hard or when the suspension is compressed more than normal. As the suspension is compressed the brake plate rotates, effectively shortening the cable or rod and applying the brake, which, once it has locked up, will stay that way, as the torque reaction when the brake is applied does the same thing. The easiest solution is to ensure correct routing of the brake cable and plenty of slack; the problem with this is that someone else using the bike or a later owner may adjust the cable to remove the slack. The more permanent solution is to change the arm to the later, upward pointing version by modifying the lug for the cable on the frame so that the cable is pointing upwards and to fit the later cable and return spring, drilling a new hole for the spring in the brake plate and re-positioning the cable adjuster lug on the brake plate. See also our cables section, for a drawing showing the correct routing for the rear brake cables.

1950 7” brake with standard bolt on ring sprocket, torque arm on rigid frames and lug on plunger models, the plunger version used the standard brake plate.

1951-52 Sprocket and brake drum cast as one item and brake increased to 8” diameter, brake plate now cast aluminium without dust excluding rim.

1953 Cable operated brake on plunger and swinging arm frames only, spacer next to brake plate is deleted as it is incorporated in the casting, dust excluding rim added. Thread on spindle changed from 12 to 20 t.p.i.

1954-58 Style of fixed spindle nut and head of main spindle altered.

Type 10 Bolt on ring sprocket, 7”, rigid 1950 only and optional
Type 11 Bolt on ring sprocket, 7”, plunger frame, 1950 only
Type 12 Combined sprocket and brake drum, 8”, rigid, 1951-55 optional
Type 13 Combined sprocket and brake drum, 8”, plunger frame, 1951-58 standard on SQ 4, optional on other models
Type 14 Combined sprocket and brake drum, 8”, swinging arm frame, 1954-55, optional and rare

For more information on wheel rims & spokes please click here