The numbers on your Z2 dial are the gap between the burrs in microns (µm), not the particle size. Use the ranges below as a starting point. Every bean, roast, and burr set behaves a little differently, and output can vary slightly from dial to dial.
Starting points
| Brew method | Burr gap range | Typical starting area |
|---|---|---|
| Turkish | 25 to 100µm | |
| Espresso | 50 to 300µm | 50 to 250µm |
| Filter machine | 500 to 1000µm | |
| Pour over | 400 to 900µm | 450 to 650µm |
| Cold brew | 700 to 1400µm |
80mm burrs often need to go finer than 64mm burrs for the same drink, and cast burrs like Lab Sweet can land anywhere from very fine to fairly coarse for espresso while they season. Start coarser and work finer.
RPM
The Z2 runs from 200 to 2000 RPM. Adjust the RPM knob on the left side while the grinder is on, but not while beans are actively grinding. 900 RPM is a great place to start. We recommend at least 300 RPM for everyday use. Speeds down to 200 RPM are there for experimenting; at fine settings the motor may stall at very low speeds, so feed beans slowly.
| Low (below 600) | Mid (700 to 1400) | High (above 1400) | |
|---|---|---|---|
| Character | More clarity, fewer fines, better uniformity | Balance of quality and speed, great for most brewing | More texture, fastest grind |
| Approx. speed | 0.5 to 1 g/s | 4.5 to 5 g/s | 6.3 to 7 g/s |
Dialing in by taste
Too bitter: grind coarser, shorten extraction, lower water temperature, check the roast date, or try a lighter roast.
Too sour: grind finer, lengthen extraction, raise water temperature.
Espresso runs long (over 30 to 35 seconds for a double): grind coarser, tamp lighter, or dose slightly less.
Espresso runs short (under 20 to 25 seconds): grind finer, tamp firmer, or dose slightly more.
Change one variable at a time and taste the difference.
Shots gushing no matter how fine you go?
That is almost always false chirp, not a fault. See Troubleshooting: False Chirp and Zero Point Shift on the Z2.