When to Replace Grinder Burrs: Signs Your Burrs Are Worn

Your grinder's burrs do more for the taste of your coffee than almost anything else in your setup. Over time their cutting edges wear down, and the grind becomes less consistent without you necessarily noticing. Here's how to tell when your burrs are due for replacement, and how to make them last longer.

Signs your burrs are worn

• You keep grinding finer. If you've gradually had to move to a finer setting to get the same shot time, worn burrs are a likely cause.
• Inconsistent shots. Shot times and flavour vary more than they used to, even with the same beans, dose and technique.
• More fines and clumping. Worn burrs crush rather than cut, producing more dust-like fines and clumps.
• Sour and bitter at the same time. An uneven grind under-extracts some particles and over-extracts others, giving a muddled, harsh flavour.
• Slower grinding. The grinder takes longer to produce the same dose.
• Visible damage. Chipped teeth, rounded edges or rust on the burrs mean they need replacing.

How long do burrs last?

Burr life depends on the burr size and material, the type of grinder, and most importantly how much coffee goes through it. A home grinder making a few coffees a day can run for years before the burrs need changing, while a busy cafe grinder may need new burrs every year or so. Lighter roasts are harder and wear burrs faster than darker roasts. Rather than relying on a fixed timeframe, watch for the signs above and have the burrs checked at each grinder service.

Is it the burrs or does the grinder just need a clean?

Old coffee oils and fines build up in the burr chamber and chute, which can cause clumping, retention and stale flavours that mimic worn burrs. Before replacing anything, give your grinder a thorough clean. Our guide on how to clean a coffee grinder properly shows you how.

Replacing burrs the right way

Always fit genuine burrs made for your grinder model. After replacement, the grinder needs to be aligned and recalibrated, and new burrs need a short seasoning period before they settle into their best performance. If you're not comfortable doing this yourself, our technicians can fit and calibrate new burrs as part of a grinder service.

Making your burrs last longer

• Clean your grinder regularly to stop oils and fines building up.
• Keep stones and foreign objects out of the hopper. One small stone can chip a burr.
• Only adjust the grind setting while the grinder is running, if your manual recommends it.
• Have your grinder serviced every 18 to 24 months for home use.

Grinder servicing in Adelaide

We service and repair home and commercial grinders from all major brands, including burr replacement, motor repairs and calibration. See our Eureka grinder repairs, Mazzer grinder repairs and Fiorenzato grinder repairs, or our general coffee machine and grinder repairs. Ready for an upgrade instead? Browse our home coffee grinders.

Frequently asked questions

Can I sharpen grinder burrs?

No. Burrs are precision-made and can't be sharpened effectively. Worn burrs should be replaced.

Do I need to replace both burrs?

Yes. Burrs work as a matched pair, so they should always be replaced together.

How often should a grinder be serviced?

Every 18 to 24 months for home grinders, and more often for commercial use.