FWIW, it's taken me years (3+) to finally figure out the Professional and the beans and the grind and the times.

I don't have the best grinder in the world (according to forum experts), but it'll do. I try to buy espresso beans that are within a week of roasting. I let these sit in an airtight container for another week to gas out.

For the beans I use now (from a local roaster), my grinder is set at 5 initially to get the most taste. 5 seconds of pre-infusion and 20 seconds of pull time. There is no crema. And I don't drink it black (always with steamed milk) so I don't really know if it's sour or not, plus the milk tends to mask that. As the beans age, I reduce the grind to one or two settings above bricking. When the water flows right through at these lower settings, I toss the beans out as they're stale.

When I first bought the Professional, I, too, was disappointed with the pulls. But as you get used to the machine and its quirks, and you finally find beans that have the potential for a God Shot, you'll eventually be able to produce reliable, tasty shots regularly. Occasionally, something will hiccup, though. It's the nature of the beast.

The views expressed here are mine based on experience. I do not have thermometers on the grouphead, nor do I have any other mechanisms to insure the best shots ever. Everyday is a crap-shoot. And I can't live without it.

If your single basket looks like the one on the left of the following pics, the best use of it is hiding in a drawer. The right hand one is workable but still not quite as good as the double baskets. The left hand design is a real hair puller. So much so that its frustration factor will take some of the shine off finally managing to pull a good shot with it.

Thanks all - yes I have started to use the double filter and results are much better.. still a few questions though:

channeling:
- Is channeling a result of bad distribution and/or tamping only or can it be for other reasons too? I am really cautious about the coffee distribution and the puck does not look like damaged or cracked but the flow suggest there might be channeling anyways...

Initial drops:
- Is having initial drops with the lever up a strict requirement? I don't get any, irrespective of how long I wait for

Coffee flow:
- Is it normal that when pulling the lever down I face significant resistance at first? like drops do not come up until the lever is almost half way down, afterward the flow starts to increase and the resistance goes down... is this normal?

Temperature:
- I pull coffees all the time with around 0.7-08 bar and always flush some hot water from the group head before pulling my first coffee. However, the coffee is always cold for me and I believe that might be also one of the reasons for the taste to be sour. Any thoughts on this?

Thanks guys! appreciate al your support

Increase of flow during the shot is normal. How much, depends on coffee. With darker roasts increase is small, with lighter roasts it's bigger. With longer preinfusion it's bigger. And grinder quality also matters to some extent

Time to 1st drop depends on preinfusion pressure. With 0.7-0.8 bar is can't be fast. It's definitively not a requirement on any machine, but just a way to achieve more repeatability by making the profile similar from shot to shot. You can make 2 step preinfusion (1st step using boiler pressure, 2nd step using some force on the lever, before increasing to extraction pressure). With darker roasts you may also get better results without preinfusion. It depends ...

Only severe channeling is visible as cavities when observing spent puck surface. Channeling / uneven flow can be less severe - in that case you will notice that some parts of puck are softer than other

As about coffee in the cup being too cold ... make sure you purge the boiler properly before making coffee; if there is air left inside, actual water temperature will be lower than it should be + you will get a lot of bubbles in the milk if steaming it ...

nm36 wrote:Temperature:
- I pull coffees all the time with around 0.7-08 bar and always flush some hot water from the group head before pulling my first coffee. However, the coffee is always cold for me and I believe that might be also one of the reasons for the taste to be sour. Any thoughts on this?

I think the group head temperature definitely plays a role in the problems you are describing. A to cold group will lead to more acidic taste, less crema and can also be a source of channeling/weird flow behaviour.
You can raise the group temperature by doing 'half pumps' (raising the lever without letting water out and lowering it again) this will replace the water above the piston with warmer water from the boiler.
Having a way to measure the group head temperature helps (temperature strips, thermometer/infra red thermometer) though I tend to rely on touch (though I won't directly reccommend it since you do run the risk of burning your fingers).
Cheers,
Rob

Kaffee Bitte wrote:The left hand design is a real hair puller.

The one on the left looks like a basket adapter to use ESE-branded pods in a conventional machine.

RobAnybody wrote:I think the group head temperature definitely plays a role in the problems you are describing.

This.

100% this.

Also, these are the single baskets I use for 58mm groups. I'm not sure if there is an equivalent for the La Pavoni groups...




The hole distribution on this is terrible, but the quality of what comes out is not. I dose 8 or 9g in them, distribute with WDT and then tamp with really repeatable and delicious results. Granted, I pull really good doubles, too

One benefit of these is that if you have two of them, the second one doubles as a tamper.

8g in:


Second basket as a tamper:


Ready to go:


All done!

It does, doesn't it. I think the pod adapters were designed around these old single basket style. Most commercial machines have a similar single. Need special tampers just to barely pull a marginal shot.
The right basket came with my Stradivari in 2008, and is still in use on occasion and as easy as a double. The left came with the new Pro and sits in a parts drawer.

I will add that temp surfing without any idea of grouphead temp is also a recipe for frustration. But a temp strip is fully workable and so cheap. It lets you dry pump to raise group temp reliably. On my Stradivari it's three pumps for 5 deg C. On the 2020 Pro it's about two pumps per 5 C rise. So much easier than running water through the group, as it is easy to overshoot.

Jake_G wrote:Also, these are the single baskets I use for 58mm groups. I'm not sure if there is an equivalent for the La Pavoni groups...

I don't know of one.

I have a relatively large collection of 49mm single baskets from/for Pavoni, Olympia, and Elektra - from the thick steel baskets of 50+ years ago to the current LF aftermarket version. Currently I mainly use the Elektra single as I cut-down a tamper to get a good seal to the 'side' of the basket with 6.5g-7.5g doses (along with a thin puck screen).

Jake_G wrote:... One benefit of these is that if you have two of them, the second one doubles as a tamper. ...

Neat trick to use one basket to tamp the other - note there are 3d-files around now to print a 58mm/41mm tamp-thru funnel and accompanying 41mm tamper.

You've got great advice here. My vote is on grouphead temp. Best to monitor it with temp strips or a digital thermometer. Start your pull around 84-85°C.
-Bruce