BS ISO 5775-2:2015 pdf free
BS ISO 5775-2:2015 pdf free.Bicycle tyres and rims
This part of ISO 5775 specifies rim dimensions for bicycle tyres: it gives only those rim contour dimensions necessary for tyre mounting and to fit the tyre on the rim.
ISO 5775-1 covers designations and dimensions for tyres.
ISO 5775-2 covers straight side (SS) rims, hooked bead type (HB) rims and crotchet type (C] rims.
The following symbols are used in this part of ISO 5775:
A Rim width
D Specified rim diameter
D1 Measured rim diameter
D2 External diameter
Dm Measuring mandrel diameter
G Flange height
H, H1 Unobstructed minimum depth above rim base with rim tape fitted to permit tyre fitment
L Theoretical tape length
L1 Well width above rim tape
P Bead seat width
R1, R2 Flange radius
R4 Well top radius
W Measuring tape width
The rim valve hole shall be centred on the bottom of the rim well. On the tyre side, the edges have to be rounded or chamfered. On the hub side, the edges shall be free from burrs which could damage the valve.
Designation and dimensions for straight side rims, hooked bead type rims and crotchet type rims are given in Clauses 4, 5 and 6 respectively.
Width and thickness of rim base protection shall be chosen in such a way as to guarantee the complete covering of the spoke heads and spoke holes during use, as well as a stable lateral fit, and to permit satisfactory ftting of the tyre and the tube.
Dimensions and tolerances of straight side (SS) rims shall be given in Figure 1 and Table 1
Straight side rims are to be used only with non-foldable tyres (rigid bead tyres).
The nominal rim diameter code, specified rim diameters and measuring rim diameters for straight side (SS) rims has to be given in Figure 1 and Table 2.
A straight side (SS) rim shall be designated by its nominal rim diameter code and its nominal width code, optionally preceded by“SS” for straight side.
EXAMPLE SS 400×20.BS ISO 5775-2 pdf download.
