Yesterday's espresso was sweet and full. Today, the same bag and the same grinder setting give you a thin shot that finishes several seconds earlier. Before turning the dial, weigh the grounds in the basket and check how much espresso is actually in the cup. A smaller dose or a different stopping point can make the comparison misleading.
If those measurements match, look at puck preparation and how the coffee has changed since opening. Beans continue to release gas after roasting, and an espresso recipe may need a small grind adjustment as the bag ages. A faster shot alone does not mean your grinder has lost calibration.
Compare the same amount of espresso
Imagine a recipe using 18 g of coffee to make 36 g of espresso. Yesterday it reached 36 g in 29 seconds; today it reached the same weight in 22 seconds. That is a useful comparison. Comparing yesterday's 36 g shot with today's 28 g shot tells you much less.
Use a scale under the cup and start the timer at the same point each time. Keep the basket, machine program and preinfusion setting the same, too. The numbers above are an example, not a target every coffee needs to hit. If the quicker shot still tastes balanced, you may not need to change anything.
Weigh what reaches the basket
A timer repeats grinding time. The weight it produces can vary with the grind setting, bean feeding and coffee left in the grinder. If the basket contains less coffee than yesterday, the puck can offer less resistance and the shot may run faster.
Tare the empty portafilter or dosing cup, then weigh the ground coffee. If you transfer from a cup, check that the intended dose actually reaches the basket. With single dosing, weighing beans before grinding is useful, but checking the output helps catch a short dose.
The MOKKOM 64mm Flat Burr Grinder lets you adjust grinding time in 0.1-second increments. Once the grind setting works, use the timer to fine-tune the dose and check it with a scale. If you change the grind size, check the dose again before comparing shots.
Look for an uneven puck
If the dose is correct, repeat your preparation carefully. Start with a clean, dry basket. Distribute the grounds evenly and tamp level. Avoid knocking the portafilter after tamping.
Water can find easier routes through an uneven coffee bed, a problem called channeling. A shot that suddenly gushes or sprays from a bottomless portafilter is a reason to check preparation. A shot can also channel without obvious spraying, so appearance alone is not a complete diagnosis.
Pull another shot with the same recipe before making a large grind adjustment. If the next shot returns to normal, work on repeating that preparation. Pressing much harder with the tamper is not a dependable way to correct an uneven puck.
The beans change while the dial stays still
An opened bag of coffee does not stay unchanged. As beans rest and release gas, their behavior in espresso can shift. Some coffees begin to run faster at the same dose and setting, and a slightly finer grind may bring the recipe back into balance.
There is no fixed schedule for this adjustment. Roast level, time since roasting and storage all matter. A gradual change across several mornings fits this explanation better than one unusually fast shot between two normal ones. Keep the bag sealed between uses and away from heat and moisture.
Let taste help you decide. A faster shot that is now thin and sharply sour is a useful reason to test a finer setting once dose and preparation are consistent. A sweet, enjoyable shot does not need correcting just because the timer shows a different number.
Make the next adjustment small
Keep your dose and target liquid weight fixed, then move a small amount finer within the espresso range, following your grinder's adjustment instructions. Pull another shot and compare the taste as well as the time. Changing dose, grind and yield together makes it hard to tell which change helped.
If you recently switched from a coarse brew setting back to espresso, some grounds from the earlier setting may remain in the path. Clear the transition as directed for your grinder before judging the new setting. There is no single purge weight that fits every grinder.
Our espresso grind size and dial-in guide explains how to work with dose, yield and grind size. Once the coffee tastes right, record those measurements alongside the setting so you have something useful to compare tomorrow.
When to check the equipment
If the change started immediately after removing and reinstalling a burr assembly, check the model-specific assembly instructions before chasing a new recipe. A scale reference reset and a burr alignment check are different tasks; neither should be assumed necessary from shot time alone.
If repeated shots stay unusually fast despite a verified dose, careful preparation and sensible grind adjustments, check whether the machine program, basket or grinder setup changed. For unexpected mechanical behavior, contact support with the model, coffee, dose, yield, shot time and a short video. Those details are more useful than saying the grind looks fine.
For a new setup, you can compare adjustment and dosing options in the MOKKOM coffee grinder collection. For the grinder already on your counter, start tomorrow with the scale: confirm the dose, stop at the same yield, taste, and then decide whether the dial needs to move.
