4 oz Accelerated (4A) Upgrade 

For the MACH III, Firefly, and Echo

Accelerated Upgrades include everything you need to add a new size to your wheel base:

  • A head (attaches into the base of your wheel)
  • A flyer (has a back with whorls, arms, and an orifice bar and holds the bobbin)
  • A hook orifice bar (attaches to the flyer magnetically)
  • A bobbin (slides onto the flyer and is secured to the back with a magnet)


Many of our fine-spinning customers requested higher ratios, so we designed a head upgrade with a built-in accelerator for short staple spinning. As far as we know, these are the highest ratios available on upright wheels in the industry today. 

  • MACH III accelerated ratio goes up to 1:52
  • ECHO accelerated ratio goes up to 1:40
  • FIREFLY accelerated ratio is variable 

This upgrade is available as a 4 oz size only. When you are spinning at such high speeds, the smaller the bobbin - the better the performance. Also, since these speeds are for spinning the finest of yarns, a 4 oz bobbin is perfectly adequate for those weights. 


  • 4A Echo Upgrade (no base): $549
  • 4A MACH/Firefly Upgrade (no base): $549
  • Echo Wheel with 4A Head & 3 4 oz bobbins: $769
  • MACH III Wheel with 4A Head & 3 4 oz bobbins: $1199
  • Echo Package with 4A + 8 oz + accessories: $1469
  • MACH III Package with 4A +8oz + Accessories: $1919