If you can't remember the last time you changed your espresso grinder burrs then chances are they could be dull. In fact, if you grind coffee, and I'm sure you do, then your burrs are slowly dulling each and every time you turn on your espresso grinder. This goes for all the your bulk grinders too, though their burrs tend to last significantly longer.
"SO WHEN DO I CHANGE MY BURRS?"
THE OFFICIAL ANSWER
The easy answer is to change your burrs using the grinder burr manufacturer's recommendations:
Anfim Caimano (75mm flat burr) – change at 1,300lbs throughput
Bunn G Series - change at 40,000lbs throughput
La Marzocco Swift (64mm ceramic flat burr) - change at 3,300lbs coffee throughput
Mahlkonig K30 – change at 1600lbs coffee throughput
Mahlkonig EK43 – change at 14,300lbs coffee throughput
Mahlkonig Tanzania – change at 8,000-10,000lbs coffee throughput
Mazzer Mini (58mm flat burr) – change at 660lbs coffee throughput
Mazzer Mini E (64mm flat burr) - change at 660lbs of coffee throughput
Mazzer Super Jolly (64mm flat burr) – change at 880lbs coffee throughput
Mazzer Major (83mm flat burr) – change at 1,300lbs coffee throughput
Mazzer Kony (63mm conical burr) – change at 1,640lbs coffee throughput
Mazzer Robur 110V (71mm conical burr) – change at 1,700lbs coffee throughput
Mazzer Robur 220V Three Phase (83mm conical burr) – change at 1,800lbs coffee throughput
Nouva Simonelli MDX (64mm flat burr) - change at 1,200lbs coffee throughput
Nouva Simonelli Mythos (75mm flat titanium burr) - change at 3,500lbs coffee throughput
Burr life is calculated by burr size and the amount of coffee put through each grinder. While there are recommended grinder burr life spans, these will vary for both flat and conical burrs, the burr material, and size ( i.e. cutting surface area) of the burr. Smaller grinders use small burrs. For example, the Mazzer Mini uses a flat burr set 58mm in diameter, this cutting surface sees a lot less action than the Mazzer Major flat burr set which measures 83mm in diameter.
Premature burr wear can be caused by rocks, nails, etc., that aren't removed in the roasting and bagging process. Motor shaft and/or bearing damage can also accelerate burr deterioration.
THE COFFEE PROFESSIONAL'S APPROACH TO ESPRESSO GRINDER BURR LIFE:
For the coffee professional, the manufacturer's recommended replacement standards take the burrs far past their personal threshold of quality. The extreme perspective might call for one to change their burrs at the half-life. So your 880lbs becomes 440lbs and so on. We suggest to our customers that you just be aware of the condition of their burrs. If you are quality oriented and find yourself particularly sensitive to negative effects dull burrs can have on espresso flavor or consistency, Espresso Parts recommends to start looking for signs of wear beginning from 50%-75% of the recommended burr life. (See chart above) It's a fine line. As long as things are looking and tasting great you are probably good to go.
WORN BURRS: THINGS TO LOOK FOR
1. Grind consistency. Are your grounds similar in size with very little variation?
2. Taste. Does your espresso taste flat no matter what you do?
3. Burr edges. Do they feel dull?
4. Inconsistent shot times. Are your shot times jumping around shot to shot, even though you aren’t making any changes?
To prolong the life of your burrs keep them clean. We find that Urnex Grindz does a terrific job of cleaning the burrs and removing lodged solids and oils. Removing, thoroughly cleaning, and re-installing grinder burrs regularly will also help extend their life.
Brand new burrs can require a breaking in or “seasoning" period before they achieve the consistency you might desire. It’s a good idea to save a few pounds of old coffee so that you have something other than fresh coffee to break those bad boys in. Uncooked rice can be a great alternative. Mazzer Robur burrs are probably the most notorious for requiring such a break in period.
ESPRESSO GRINDER BURR CHANGING TUTORIAL
If you are feeling ambitious, we have a tutorial for that below. Remember to ALWAYS use caution and ALWAYS UNPLUG YOUR GRINDER before starting to work on it.
Tools Required: Two screwdrivers and possibly an adjustable (Crescent) wrench
1. Remove the bean hopper. Make sure gate at neck of hopper is closed! Run a dose of Grindz through the machine to make cleanup that much easier once you get inside.
2. UNPLUG GRINDER. Push down grind adjustment lock and unscrew upper burr carrier all the way. The direction will vary depending on the brand of grinder you are working on. Some grinders do not have an adjustment lock and simply use tension springs and a fixing screw to hold the grind adjustment collar.
3. There will be one burr on the bottom of the burr carrier you just removed and one inside the grinding chamber attached to the motor shaft. (Each burr is held in place with two or three screws). Using a screwdriver, remove the screws from the burr that is attached to the upper burr carrier and remove the old burr – this is the easy one.
4. Removing the lower burr is a bit more complicated, as it is attached to the motor shaft and will want to spin. Using an additional screwdriver (or adjustable wrench on the fixing bolt), hold the lower burr carrier in place while releasing the burr attachment screws. Be careful not to damage the surface of the grind chamber by sticking a screwdriver through the chute or wedging something on one of the fins.
5. Make sure that you remove any and all coffee residue from the mounting surfaces of the burrs. Also clean all the adjustment threads on the upper burr carrier prior to installation. Now is the time to do a thorough cleaning of the entire burr area.
6. After everything is thoroughly cleaned, install the new set of burrs. Do not completely tighten down each screw at one time, make sure to alternate. Tighten each screw a little at a time until all screws are tightened evenly. This will ensure the burr is tightened down equally all the way around to prevent any unevenness.
7. Replace the upper burr carrier by screwing it back in. You should put just enough lube on the clean threads of your upper burr carrier to make the threads shiny. No more. You do not want to have any excess lube contaminate the grind chamber. CAUTION: It is extremely important that you use caution when reinstalling this part. Do not force the carrier into place, as you will damage the adjustment threads (an expensive mistake). If you place the carrier into position then thread it backwards, you should feel the collar drop into place and it should screw in much easier.
8. Once you have the collar in place and have screwed it in by a few turns then you can plug the grinder back in. With the bean hopper off and the power on screw the collar all the way down until you hear the burrs barely touching then turn back one half turn. At this point you should be about right for your grind and from this point you can begin to “fine tune" your grind. For more info on dialing in your grind, check out our tutorial on adjusting your grinder.
Find your set of new espresso grinder burrs in our Espresso Grinder Burr section of our website.
Find accessories to help make that burr swap a snap in Espresso Grinder Cleaning.
If you need more help we have an awesome customer support team that would love to help you! Please call us at 1-800-459-5594 or email firstname.lastname@example.org