Technically the whorls are the pulley which drives the flyer. All the double drive wheels use the same spindle shaft and thread and all the pulleys can be used iinterchangeabley. The Minstrel whorls/pulleys are smaller, which can be a useful addition to the Symphony and Polonaise if you are looking for those in between ratios.
We keep all the options in stock, from the extra slow jumbo pulley, througfh standard paired pulleys to the extra fast high speen optionw which is a must for spinning high twist fine threads without falling asleep at your wheel or falling into the easy trap of not spinning with enough twist.
The whorls/pulleys are the same price regardless of size, at £13 in bare wood ab=nd £16.50 in clear or coloured finishes. More images to be posted soon, see here for more information.