Breville Barista Express (BES870) Espresso Grind Settings
Curated espresso settings from 2–8 grind size number with roast-specific zones, sensitivity data, and calibration guidance.
Grind Settings by Roast Level
Recommended grind size number ranges for each roast level on the Barista Express (BES870).
| Roast | Low | Center | High | Confidence |
|---|---|---|---|---|
| Light | 2 | 4 | 5 | C |
| Medium-Light | 3 | 5 | 6 | C |
| Medium | 4 | 5 | 7 | B |
| Medium-Dark | 5 | 7 | 9 | C |
| Dark | 6 | 8 | 11 | C |
Values in grind size number. Center is the best starting point; low/high represent the typical range across different beans.
Sensitivity Zones
How much shot time changes per adjustment step in different zones of the dial.
Fine End
BMost sensitive zone — small changes have big impact on shot time
Mid Range
BSweet spot for most espresso — moderate sensitivity
Coarse End
CLeast sensitive — larger adjustments needed to affect extraction
Tips & Quirks
Things to know about dialing in the Barista Express (BES870).
Stepped grind adjustment with large steps means you may not be able to dial in perfectly. If one setting runs too fast and the next too slow, compensate by adjusting dose (plus or minus 0.5-1g) or adjusting the inner burr by one position and moving the outer dial in the opposite direction.
The inner burr adjustment requires removing the hopper and burr assembly. It is NOT designed to be changed frequently. When reassembling, align the arrow on the burr with the 'ALIGN' mark, insert, and twist clockwise to lock. Misalignment can cause inconsistent grinds or grinding noises.
Grind retention is approximately 1-2g. The first shot after changing grind settings will contain a mix of old and new grind sizes. Purge 2-3g of beans through the grinder after any adjustment before pulling a shot you intend to evaluate.
The built-in grinder produces noticeable clumping, especially at finer settings. Use WDT (Weiss Distribution Technique) with a needle tool to break up clumps in the portafilter before tamping for more even extraction.
The factory inner burr default of 6 is calibrated for medium roasts. Many users with light or medium-light roasts find the grinder 'cannot grind fine enough' at the default — this is the single most common complaint. The fix is to lower the inner burr to 3-4 (not to buy a new grinder).
The built-in dosing timer is inconsistent. For best results, weigh whole beans before adding them to the hopper and single-dose, or weigh the ground output and adjust as needed. Target 18-18.5g for the included double basket.
Clean the grinder burrs and chute every 2 weeks or after approximately 2kg of beans. Coffee oil buildup in the burr chamber causes clogging, inconsistent grind, and stale flavors. Vacuum the burr chamber when adjusting the inner burr.
Aftermarket upgrades are popular: silicone bellows (reduces retention to near-zero), IMS precision baskets (better extraction than stock dual-wall baskets), and bottomless portafilters (for diagnosing distribution issues). These do not void warranty but significantly improve results.
Calibration
Unit-to-unit variance and zero-point info for the Barista Express (BES870).
Variance
Zero Point
No traditional zero/chirp method. Outer dial stops at 1 (finest). Inner burr 1 + outer dial 1 is absolute finest but chokes most shots. Dial in by targeting 25-30 sec for 18g in / ~36g out. Procedure: start factory defaults (IB6/G5), pull shot, adjust outer dial finer if too fast (<20s) or coarser if too slow (>35s). If out of outer dial range, adjust inner burr by one position and reset outer to middle.
Dual-adjustment system introduces significant unit-to-unit variance. Inner burr positions are not precisely indexed — alignment during reassembly affects actual grind size. Two machines at same IB/G numbers can produce different grinds.
Specifications
Get Your Exact Setting
These are starting points. Your unit is different. Calibrate with GrindDial and get a personalized grind setting in 1-2 shots.
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