Mythos was positioned as one of the lowest retention hopper-fed grinder due to its inclined burrs design. So it happens that one of these came into my possession
and I decided to put it to test. What I am measuring is the total retention in the system, disregarding whether it is static or dynamic retention
. Dynamic retention (the practical retention) will likely be lower because there'll be some compacted 'ground' that never get mixed into freshly ground coffee.
First, the obvious - chute:
~3.2g in the chute. As you can see in the pic above, the older chute retains quite a bit there. It should be reduced greatly with the new clump crusher.
This was how it looks immediately affter disassembling the upper burr mount. Do note that I can't remove 100% of the beans above the burrs prior to disassembly. So all these were removed and sieved for measurement. The chute's retention was collected first, separately):
Separating the whole beans that I didn't manage to remove prior to disassembly:
Partially ground+fully ground
Separated the bigger chunks using a fork: ~1g of chunks, and ~8.3g of fully ground coffee.
Edit: I sieved the 'fully ground' portion with a finer mesh and there are about 2.3g extra chunks(partially ground coffee). So it should be ~3.3g chunk and 6.0g fully ground coffee.
In total, there is a total of about 12-13g coffee retained in the (older) system. With the new clump crusher, I would expect that to be about 9-10g. It's not totally zero retention, but pretty good for a hopper feed system.