An inconsistent BES878 or SES878 dose should be separated from a blocked grinder. Confirm the filter-basket selection, grind amount, burr seating and dry bean feed, then compare timed manual doses on the same settings.
Dose changes can come from a different single or double basket choice, a changed grind-duration setting, beans feeding unevenly, or the upper burr returning to a different numbered position after cleaning. Use one basket, one bean batch and one grind size for comparison. Weight is more useful than judging the mound visually because distribution changes its apparent height.
Follow the checks in order and change only one condition at a time. Run a short rinse or test after each action, so the result identifies the cause instead of hiding it. The procedures below stay within the cleaning, refitting and user-menu operations described by the manufacturer.
Models covered
Safety first
- Unplug before removing hopper or upper burr, keep grinder parts dry and never reach into the lower burr. Use only the removable components and brush procedure described by Sage or Breville.
What the symptom may indicate
Checks in the right order
- Fix one test setup
Use the same empty dry single or double basket for every test, select its matching dose setting and leave grind size unchanged.
- Confirm hopper and upper burr
With power off, confirm the hopper and upper burr are both turned to their locked marks. If cleaning was recent, verify the burr’s numbered adjustment against the recorded value.
- Clear dry retained grounds
If feed is uneven, unplug, empty the hopper and use the supplied dry brush on the removable upper burr and grind outlet before reassembling.
- Compare timed manual doses
Run two short manual grinds for the same duration, weighing the dry output if possible. Similar results show the mechanism is consistent; adjust the programmed amount only after that.
Stop and get qualified help when
- Stop if dose changes come with harsh noise, a stalled motor, burning smell, chipped burr, hopper that will not lock, or an output interruption that returns immediately after dry cleaning.
Next step
Repair, replace a part, or arrange a diagnosis?
Use the checks and stop conditions above to choose the least costly safe next step. A symptom alone never proves that the appliance has failed.
Resolve it without buying anything
Complete the 4 safe checks in order. If normal operation returns and no warning sign remains, no replacement is indicated.
Replace only the confirmed part
If the checks isolate a worn or blocked component, match its complete reference to the exact appliance model before ordering.
This guide does not identify a replacement part. Do not order a generic component from the symptom alone.
Arrange a diagnosis before replacing the appliance
Stop at any warning sign listed above. A qualified diagnosis should confirm that repair is unsafe, unavailable or uneconomical before an appliance replacement is considered.
Stop and get qualified help when : 1
Compare replacement appliances on AmazonPaid Amazon search. Results are suggestions, not a diagnosis or a recommendation to discard the appliance.Sources used
- Sage — The official Barista Pro manual separates steam, grinder blockage, abnormal noise and dose-setting checks for BES878 and SES878.
- Sage — Sage documents removal and cleaning of the Barista Pro hopper and upper conical burr, without opening the appliance body.
Last checked: 29 August 2026