Adjusting Grind Size on the E65 GBW
1. Adjusting Grind Size on the E65 GBW
The Mazzer E65 GBW is a stepless grinder, which means you can fine-tune your grind very precisely. Here's how to do it safely and effectively:
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Unplug the grinder (optional, but safe if you’re going to handle burrs).
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Locate the adjustment collar – it’s the rotating ring at the top where the burrs meet.
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Turn to adjust:
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Finer grind → rotate the adjustment ring clockwise.
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Coarser grind → rotate the adjustment ring counter-clockwise.
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Make small changes: Even a 1/8 turn can make a noticeable difference in extraction.
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Check the dose: Grind a normal shot amount and see if the flow rate changes.
⚠️ Tip: If you need to adjust for a faster extraction, make the grind slightly coarser. If it’s too fast, make it finer.
2. Understanding Extraction
Extraction is how much of the coffee’s soluble flavors dissolve into the shot. The grind size has a huge impact:
| Issue | Likely Cause | Fix |
|---|---|---|
| Under-extracted (sour, thin, fast shot) | Grind too coarse, low dose, or tamp too light | Make grind finer, increase dose, tamp evenly |
| Over-extracted (bitter, slow, hollow taste) | Grind too fine, high dose, too much tamp | Make grind coarser, adjust dose, check tamp |
| Uneven extraction | Inconsistent grind, tamp, or distribution | Distribute grounds evenly, check burr wear |
Shot timing is a good guide:
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Standard espresso: 25–35 seconds for a 30ml single or 60ml double.
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Flow should be steady, like warm honey dripping, not blasting or barely trickling.
3. Practical Tips
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Dial in with taste: Don’t rely on time alone; taste is the ultimate measure.
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Keep burrs clean: Old coffee oils affect extraction. Clean weekly.
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Dose consistency: Use a scale for repeatable results.
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Check espresso yield: If your double is 18–20g in, aim for ~36–40g out. Adjust as needed.
If you want, I can make a quick visual “cheat sheet” for E65 grind adjustment and extraction troubleshooting, so you can tweak it shot by shot without guessing.