Mahlkonig E65S GBW - user experience - Page 6

Grinders are one of the keys to exceptional espresso. Discuss them here.

#51: Post by UrKurt »

BaristaBoy E61 wrote:As someone that has done a lot of servicing and cleaning of a Mahlkonig K30 Vario that is quite similar to the E65S GBW, I fail to see how the accuracy, not of the weight but of the total dose, can be accurate in the E65S GBW as the exit and chute design retains a lot of ground coffee that can break off and be released at any time adding to the total dose, therefore be quite different from the programmed display indicator.

The attached pics are from the K30 Vario.


Given that these images are from a K30, it seems possible that the answer is that the E65S GBW just doesn't behave this way. It would be helpful if someone with one of these grinders could open theirs up and speak to this.

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#52: Post by BaristaBoy E61 replying to UrKurt »

Yes, it would be helpful if someone would disassemble their Mahlkonig E65S GBW after 6-months of use and post images before any cleaning.

I'm not hopeful, same burrs, same motor, similar chute design. Different ascetics, fancier display, more sophisticate controls. The issue of retention is all but ignored, like it will go away if no one talks about it.
"You didn't buy an Espresso Machine - You bought a Chemistry Set!"


#53: Post by Bzuca »

I just bought an E65 GBW and am concerned about issues with the scale: a barista friend told me it's an amazing grinder, when it works. The scale hangs up and constantly needs calibration or reseting the grinder. To the point they gave up on the grinder because it was so fussy. Anyone with a similar experience?

I would lime it to just work and play nice :)



#54: Post by yyacoob »

I have the E65GBW for over a month, and I enjoy every single grind. Very quiet, fast (~4 seconds for 20grams), rather important at 5AM! I have no issues with the scale, it arrived calibrated and as of today it has been consistent, I just weighed my last grind and it came out spot on exactly 20grams as dialed. The important point is not the number but consistency from grind to grind, which it has delivered (I had only 2 types of coffee in use so far).

You can't beat the workflow and consistency. There were posts about messed up scales, which are the manufacture's responsibility to deal with. Your barista friend experience is different than mine. Please post your experience.


#55: Post by yatesd »

As an owner of a Mahlkonig K30 for 8 years, and as I shared in another thread I am very happy.

Surprised this thread seems to focus on single dose/weight based shots.

As others have stated this is a commercial grinder. It is designed to set it and forget it. I will occasionally adjust the grind time, especially if I get a different bean type, and I will occasionally adjust the grind fineness. However, where it really shines is I get extremely reliable, fast, and consistent performance day in and day out. The only time I am reminded of its existence is when it asks me to clean it every few months by running a few Grindz beans through it.

I generally buy 5lbs at a time and freeze on arrival, and then fill the 1/2lb hopper every 5 days or so.

So while I am a raving fan of this grinder, I am not sure I would recommend it for single dose, nor do I have the interest in the added complexity of that effort. I bought a scale based on the recommendation of this forum, but only think I used it once.

I like high quality espresso and want it to be fresh. Candidly, 100% of what I drink is considered "long blacks". I use a small cafe size cup, add water to the base with my Vetrano and top with a double shot. Same thing every day. No complaints. I'll make an Americano for the in-laws using more water.


#56: Post by sluflyer06 »

giboja wrote:I got mine 3 days ago as upgrade to Specialita.

It is big, nice and solid beast. Nice commercial design which can live in any kitchen.

I bought 1 kilo Italian espresso blend to run it in.

Upon start I was amazed by speed, silent running motor and clumpless grind. That was on setting 4.

When I try to make a coffee from that it just runs trough in 10 sec. I want finer and finer and hit the 0 but it was still way to coarse for any result.
As I asked seller(official distributor) to adjust it and install new software and they confirm they did it before shipping it to me across the Europe I started to worry a bit.

As instructed in video I opened it to readjust the dial and made quite a big adjustment before burrs started to make a sound. I thought that's it, but again, even being better, not even close to be fine enough.

My worry level raised so I decided to check alignment of the burrs. Off course it was badly way out of alignment.
After I spent some 3 hours playing with thin foils, marker and tinkering I put it back and check.

It was better again but still not fine enough. Here I started thinking about sending it back.
I grind 1 kilo coffee to season a bit the burrs and then opened it again to proceed with alignment.

I checked axial alignment as well and find out that it is 0.1 mm out which can be sorted if you tighten 2 bolts step by step each by bit.
What they did, I think at least. they made bolt holes on burr carrier on little bit smaller diameter (app 0,3mm) than bolt holes on burr so that bolt head pushes burr inwards from each side??
Anyway after tightening the bolts bit by bit axial alignment was perfect.

So I proceed with spinning burr angular alignment for 2 hours to get to almost satisfying result and another hour for fixed top burr.

After that, finally it was grinding fine enough for that coffee. OK
than I check it against my Eureka just to find out that Eureka is choking my machine on finest setting where that was not even close possible with GBW. But still, it is grinding fine enough so be it.

Interesting thing I noticed is that coffee grinded on GBW does not like pre infusion!!
Pre infusion on my machine is set on 2 bar and 10 seconds.
With Eureka, I get first drop after 6-7 sec, than at 10 sec 9 bar and nice flow.

With GBW pre infusion just let water flow trough the puck as soon as 2 bar is reached and then after pump start to 9 bar flow normalizes.
I checked that without pre infusion so that I adjust both grinders to get same amount of coffee in same time.

Possible explanation, maybe, is that K30 burrs(yes, same burrs in GBW) make less fines and therefore with lower pressure faster water flow??

Now goes scale. I have 1kg M2 calibration weight for proper calibration and did calibrate it.

Scale is off from time to time up to 8% for single dose, 8 gramm
Scale is off from time to time up to 4% for 16gramm

If you grind shoot by shoot back to back it gets better but after few hours first shoot can be off that much.

I got lot channeling which I never had before with Specialita. This may improve as I learn to adapt my workflow, WDT and so...

So, I am typing this, quite disappointed with grinder, it is expensive and I was expecting to be amazed by result but I am not.
Now, aligned, it can be keeper, but I am not happy with grinder for money ratio.
I expected superb quality out of box from big grinder industry name just to find out my expectation where to high.

Everything else apart from this is OK.
Can I ask..are you trying to single dose or are you putting a good amount of beans in the hopper?


#57: Post by tecnica222 »

With regards to grind quality (not workflow or aesthetics), how do you view this grinder compared to say the P100 or the EG-1? I understand it has much more of a commercial orientation, but how about grind quality?

I am looking to pair it with a Linea Mini.


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#58: Post by Jaroslav replying to tecnica222 »

The grinder didn't do well in the blind tests Kaffeemacher published, scored worse than Mignon Specialita. Michel rated it the worst of the bunch (in a blind tasting test).


#59: Post by DentalBeans »

First - this grinder is amazing.
Second - anyone mod the short hopper to add a silicone gasket or a better seal? I don't want to add a wooden top as it won't match my aesthetic (modern white/black) but I wanted to seal it a bit better for bean freshness.


#60: Post by johnsontoddr »

To add the user experience with the E65S GBW I thought I would add my experience here. I bought the grinder in Sept. 2022 to use in my espresso pop-up stand. I had been using an Orion doser and Niche Zero, but those were to slow and took up a lot of cart space. The E65S was a game changer. Instead of needing around 13 seconds to dose and grind with the Orion+Niche combo, the E65S is done in around 4 seconds and only requires me to drop the portafilter in the fork. I do other things while it is dosing, because I work the cart by myself. I only do two regular markets each month and sometimes do one or two extra. Between markets the grinder lives in its original box on the bottom of my cart that I roll into my cargo trailer. Each market, I end up making 100 to 140 espresso based drinks over 4-5 hours. I use two portafilters so that I can prep one while a shot is pouring from the other, or while milk is ghost steaming on my DE1XL.

So far so good. However, last July I set up for a market, loaded up the beans and then suddenly the grinder dosed without warning and wouldn't stop until I turned it off. I kept playing with the forks and turning it off and on and it eventually worked the entire market. Took it home and set it up--worked fine for several shots... then I heard it suddenly start grinding and by the time I got to it I lost around 1/4 bag of coffee. I ordered a 1kg weight and calibrated the load cell. That fixed the issue. I also upgraded to firmware 300.

The grinder worked flawlessly again including one week ago, but this past Saturday I set up the grinder, turned it on and it started grinding. Nothing I did, including a hard reset would stop it. I always carry the 1kg weight with me, but calibration didn't work. The grinder always showed 1808 g of weight even with nothing on the forks. I entered GBW Fail Mode and had to use the manual dozing button the entire day. Still.. I did 140 espresso-based drinks and some were double (really quadruple) shots.

Yesterday and again this evening I spent hours trying to fix the machine. I reached out to a tech who is basically telling me to keep trying to calibrate. The machine gets itself into different modes of disfunction at times, sometimes grinding on startup, sometimes just locking up on startup. At one point pressing the load cell decreased weight and raising it increased. One time, after many soft and hard resets, and also shifting the load cell around, I got the grinder to calibrate, recognize portafilters, and grind a couple of doses. I turned it off and on and it worked again, then suddenly it locked up and now the scale is off again.

I admittedly use the grinder in a pretty harsh environment. I load and unload it at least twice each month and temps here in Houston can get extreme, at least on the hot end, especially since many markets are outside and in full sun at times.

The big problem though is that Mahlkonig has clearly not designed their firmware to be robust to possible errors. The front screen should never lock up due to load cell issues, yet you can find many examples online where it does. To even get into the menu, I have to hold both left buttons, flip the machine on, then quickly double tap the scroll wheel before the recipes show up. At times now, the machine even locks up in GBW Fail Mode. The software provides little help in diagnosing the issues and it appears that the firmware has not been updated in some time. Hard to tell, because Mahlkonig doesn't give users any ability to check themselves.

Of course my machine is 2 months out of warranty, but that would not be a big deal if I could get help diagnosing issues. I had a LaSpaziale Vivaldi S1 V1 for around 12 years that ran 24/7 and all it took was a quick call to Chris Coffee and often just a 5 minute discussion with a tech and a few tests with my multimeter to know what parts I needed to order.