Hi Jayne - If your keen have a look at this. The terminology has to do with the difference between the torque required to set the bolt and then restart the tightening or loosen the bolt. Since there is no preload in a pulley connection its not useful info in this application. But since you probably do up and undo bolts the terms would be useful for you. I tried to get the iso std but the sources wanted payment...
I prefer taperlocks and have used them up to dia600mm on mining equipment axles, brand name Ringfeder but they don't make small ones. The CPT pulley looked reasonable. Peter
https://ntrs.nasa.gov/api/citations/...0120015467.pdf
https://www.ringfeder.com/products/l...oads/rfn-7012/