Eureka Olympus 75e Burr Alignment and Retention

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

Postby wholemilklatte » Nov 10, 2017, 4:40 pm

I've had this grinder for ~3 months and really like it. I've probably put 15-20# through it in that time. The double-shot counter is around 350 as of this morning. I use the manual purge option from time to time as well.

I found this article on Mythos burr alignment (link below) and figured i'd check mine out at the next opportunity. It turns out that i was between coffees and had a couple of hours to take a look at this yesterday, i thought the forum might find this interesting.

In addition to alignment i also wanted to figure out how to remove the portafilter holder which required removing the front controls and chute. (or so i thought, you can actually just pull it out with a little extra effort and put it back in too) as part of doing that i figured out how the clump smasher works and what the retention looks like. This was kind of like 10 years ago when i discovered that the manual Mazzer dosers don't stay clean on their own. :roll:

Mythos Burr Alignment Doc:


First step was to remove the hopper and top burr and then clean it out as best as possible:

Then remove the top and bottom burrs completely and clean/dry them, i forgot to take a picture, they clean up real nice though.

Following the guide i then reinstalled the burrs, centered each of them on their respective mount using paper shims (sorry, i forgot to make pictures)
Then using a blue dry-erase marker i colored the outer ring of each burr (i tried a kids couch-safe crayola marker first but it doesn't work nearly as well as the dry-erase does)

Then I ran the grinder and slowly adjusted it finer until the burrs touched. I backed it off, stopped the grinder, and removed the burrs. Looks like mine is well aligned from the factory - which is great. From the marker it looks like there might be a very minor high spot (between 1 and 3 o'clock in the top burr picture picture) but it doesn't appear significant at all. (i'd love to hear what others think)
Top burr

Bottom burr:

The mounts on the Olympus appear to be designed such that alignment is going to be pretty dead on from the factory, i imagine assembly problems could lead to mis-alignment as well, but mine was good.


I was a bit surprised about this - there's a decent amount of retention in the grinder. A regular cleaning get's a lot out of the burrs and the accessible part at the top of the grinder. I doubt this makes a difference day to day but a regular cleaning is probably a good idea, the bulk of it is around the exit hole (from burr to chute) and the clump crusher. I wasn't able to weigh it as i dumped a bunch of it in the sink before thinking about it. There were grinds in the control box as well, it was a small amount and likely just due to ineffective sealing of the compartment. I can see this accumulating over time though given that my grinder is pretty much still brand new and is only used at home.

Unfortunately the clump crusher and exit hole are not easy to clean without disassembling the grinder like i did. The flexible plastic crusher arms will likely break if i shove a brush through them too many times. I'll check this again maybe in a few months or a year and i may end up removing the crusher arms so i will be able to use a brush in the future.

First step - remove the logo sticker to reveal the screw that holds the controls on:

Second - Pull the controls off (it pops off easily, just watch out for the LED as it's just surface mounted and sort of bent into position)

The clump crusher and chute assemble is a little finicky to remove but it pops out easily enough and you can get it all back into place easily too. If i do this again it'll take me 10 minutes start to finish.

From burrs to the clump crusher - it's not a perfect fit and so the grinds fill the void

The clump crusher before i removed it - totally blocked with coffee, there's a channel in the middle where the newly ground coffee forces through - it accumulates around the edges

The clump crusher removed

This is most of what i got out of the grinder, it's not insignificant but i wasn't able to weigh it

Then reassemble and we're back in business:


Postby wai2cool4u » Nov 13, 2017, 1:13 am

cool info. thanks for posting. I was very interested in the the Olympus but this forum doesn't seem to have a lot of love for this grinder. haven't seen many owners post about it. strange considering it has the TIN coated burrs from the mythos.


Postby erik82 » Nov 13, 2017, 2:37 am

I've owned one for 2 years with Mythos burrs and thinks it's the best grinder in it's priceclass. For a 1000 euro's you get a poor mans Mythos without a lot of retention.


Postby JayBeck » replying to erik82 » Nov 13, 2017, 12:33 pm

I can't really anything out about this grinder other than what Seattle Coffee Gear has on its website and some fairly old reviews. It looks to be quite large and will not fit in many kitchens. I have the 2017 upgraded E37S coming today. I'm curious on how the Olumpus compares to its grind quality. The Ceado is much more attractive looking, looks like it has less retention, and fits in a kitchen better which may be worth the $400 premium.

User avatar

Postby redbone » Nov 13, 2017, 12:54 pm

Maybe this sizing perspective helps.

Grinder line-up from I.D.C.
Between order and chaos there is espresso.
Semper discens.

LMWDP #549


Postby JayBeck » Nov 13, 2017, 1:21 pm

redbone wrote:Maybe this sizing perspective helps.


LOL -- the Vario looks like a toy.


Postby Ellejaycafe » Nov 13, 2017, 1:38 pm

I have been looking at this grinder for a while for a new shop. My idea was to buy 2, one for our flagship blend and one for SOE. On paper the grinder looks like a no brainer. Mythos burrs rated for an insane amount of throughput, super fast, effective clump crushing, love how the grind adjustment works, looks to be well made and aligned easily, all for under $1200 bucks?! I have a few questions since there is hardly any info around about this grinder.

We use k30s right now, would anyone be able chime in on whether the 75mm burrs in the eureka will provide more consistent and better flavor in the cup? I know these burrs are loved across the globe.

Is there a cooling system on the eureka? That's one thing I wish the k30 had.(I know the air does and the peak, I am considering buying an air and using the k30 for SOEs, I feel the peak isn't geared towards our roasting style). The grinder has a very powerful motor, I'd imagine it would need a fan at least in a commercial setting. At the speed this grinder runs would overheating become a problem without a fan?

My initial plan was to wait until the compak PKR line comes out but I don't know when that will be. I will need the grinder in the next month or so to break it in and get to know it's quirks. If the PKR line wasn't announced at host I would probably buy 2 compak e8s with 83mm burrs. Does anyone know how the mythos burrs stack up to the compak e8 burrs or 83mm flats in general?

Sorry to "hi jack" your thread but I am finding it really hard to find any info on the eureka and see a few people here who own one. I'm sure anyone looking at this grinder has the same questions.
LMWDP #544


Postby wholemilklatte » Nov 14, 2017, 2:46 am

Not a problem LJ. i have a much different use case than yours. I can say that for my (home) use this grinder is great even though it's oversized for home use. I was upgrading from a Mazzer Mini so it was a significant upgrade with regard to burr size, power, dosing, and adjustability.

I'm lucky to happen to have a kitchen space for my coffee setup where cabinet height isn't a concern which helps it work.

the only thing i feel like is a bit of a downside right now is that it's really difficult to clean the full grind path, something i would do weekly, or at least with each bean change, with my mini. the grind adjustment mechanism and lack of retention far outweighs that though (IMO). I've been able to dial in my dosing so i waste little to no coffee, something that was impossible with the manual dose in the mazzer.

I recently started using the WDT and have reached another level of consistency with my extractions. now all my problems are all user error for sure - and i know it :mrgreen:


Postby erik82 » Nov 14, 2017, 12:09 pm

I've owned both a K30 Vario and the Olympus and liked the Olympus more (only with Mythos burrs). Less retention and I really liked the taste of the Mythos burrs for light roasts.


Postby bas » Nov 14, 2017, 2:19 pm

It looks to be quite large and will not fit in many kitchens.

Help is on its way! Around january 2018 the Atom with 75 mm burrs is expected. Either in steel, red speed or TiN. That means a "poor man's Mythos" in a kitchen friendly size. Sounds like the (almost) perfect home grinder.