Bayonet ring brew group Linea Mini – so the portafilter locks fully home again
The bayonet ring is the part of the brew group into which you insert the portafilter twenty, fifty or a hundred times a day and lock it with a short turn. That is exactly where metal rubs on metal, under coffee oils and heat. When this firm, defined click becomes soft, the ring is the first part you should look at.
The ring holds the portafilter and presses it against the group gasket when locking. Only if its flanks are still sharp does the group build up pressure cleanly. The manufacturer lists it for the Linea Mini under part number A.3.005.
When it is due
The portafilter can be turned further and further, the handle no longer sits in the centre. Water drips sideways out of the group during extraction, even though the gasket is new. Inserting it feels scratchy or stepped. Or you can see bare, worn spots on the flanks of the ring.
At a glance
| Type |
Bayonet ring of the brew group |
| Installation point |
Brew group, portafilter mount |
| Fits |
La Marzocco Linea Mini. For older or modified machines: send us the serial number and we will check the fit. |
| Scope of delivery |
one bayonet ring |
| Part number |
A.3.005 |
| Version |
Ring for the brew group of the Linea Mini |
| Installation |
Installation by a specialist recommended |
| Brand |
La Marzocco |
Important for installation
The ring is part of the pressurised brew group. We deliberately do not publish step-by-step instructions for it: the machine must be disconnected from the power and depressurised, and after the replacement it has to be checked whether the portafilter locks home in the centre and the group gasket still fits. This is a job for a specialist – or for our workshop.
Who it is for
For Linea Mini owners whose machine has many years and many thousands of shots behind it. For cafés where the Mini runs as a second machine or at a catering stand and is handled roughly as a result. And for anyone who has taken over a used Mini and wants to make the group healthy from the ground up.
What goes with it
Right next to it belongs the group gasket for Linea Mini R and Linea Micra, because it makes sense to replace both together. All other parts are available in Spare parts Linea Mini, Accessories and spare parts for La Marzocco and in Original spare parts.
Workshop tip from Bern and Zurich
Our own routine, not a manufacturer's specification: when the portafilter turns too far, we never replace just the gasket. We lay the old and the new ring side by side and look at the flanks in raking light – the wear is then immediately visible. After reassembly we pull a test shot with Nutty Delight, because with it you can hear and see clearly whether the group is tight. Sweeter with Cozy Chocolate, stronger with Very Nutty. Everything else in our coffee beans.
Returns excluded
Original spare parts are excluded from exchange and return. They are sourced specifically for each order and cannot be resold after being installed or test-fitted on the machine. So before ordering, check the model, year of manufacture and serial number of your machine – or drop us a line and we will clarify the fit together. Your rights in the event of defective goods remain unaffected.
Frequently asked questions
My portafilter turns too far – is it always the ring?
Not necessarily. Often the group gasket has hardened and been compressed first. Only if a new gasket does not solve the problem is the bayonet ring the next suspect.
Does the ring also fit the Linea Micra or the GS3?
This position is listed for the Linea Mini, part number A.3.005. Other series have their own positions – tell us which machine you have.
Is a gasket included?
No, the ring is supplied on its own. The group gasket is a separate position and it makes sense to replace it at the same time.
Can I change it myself?
We recommend a specialist, because the ring is part of the pressurised brew group and the machine has to be disconnected from the power and depressurised for it.
Can I look at the part in your showroom?
Yes. We are in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b. Let us know shortly beforehand and we will have the part ready.
Questions about the fit? Write to us with the model and serial number at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
