I found the following useful advice from the booklet “From Take Off to Landing”. This is an unofficial guide to PANS-OPS and TERPS, but highly rated and reliable.
PANS-OPS:- “Lead radial (shown on approach chart) provides at least 2 NM lead for turn onto intermediate approach track.”
TERPS:- “When angle of interception of the intermediate course > 90 deg, a lead radial provides at least 2 NM lead for turn onto the intermediate approach course.”
The above is based on limiting the speed to that required (mandated) when flying the initial approach segment of any procedure; aircraft category:-
A: 90 - 150 kt
B: 120 - 180 kt
C: 160 - 240 kt
D: 185 - 250 kt
The obstacle clearance and procedure flight path are compensated for wind and altitude effects:-
Statistical or omnidirectional wind; 47 kt + 2 kt per each thousand of procedure altitude.
Bank angle. The lesser of 3 deg/s turn rate or 25 deg (the latter applies for TAS > 170 kt)