Dear All,

I have recently purchased Vibiemme Domobar Super HX rotary pump and having difficulties to extract good shots. I tried three different types of coffee from different vendors. However, only a few shots were OK but rest was all failure. I don't know what I am doing wrong so I desperately seek some advice.

- My machine was always on more than an hour.
- My grinder is Mazzer LUX.
- I use btw 15 to 18 gr freshly grinded coffee. Measuring with 0.1 gram scale.
- Boiler pressure is btw 0.9-1.1 and brew pressure is at 9bar during the shot.
- I extract 33-38 gram shot between 25 to 33 seconds. I attach my last shot which took 28 seconds; used 16 gr coffee and extracted 33 gr espresso. However, you can see from the pic that it is not correct as it tastes really bad.

Any suggestion is appreciated. Thanks in advance.

One question, when was that coffee roasted ?
It looks as if it's old and stale, if you have ever smelled and tasted fresh ground fresh roasted coffee you'd be able to tell immediately...old beans smell of blackness and lack all the other aromas you'd like to taste and smell as the oils are gone. Usually these oils float on top of the espresso, there no crema to speak of and I see no oils floating.

The machine is new and your grinder too (or are both clean)?
Your brew temperature is correct?

Looks like coffee that is not fresh but could easy be temperature problem? What about your flushing routine?

Thanks for the replies.. Last coffee I used was roasted on 29 August and others were roasted a week before I used. I purchased all coffees from SCAE certified roasters. Machine is brand new purchased 10 days ago and cleaned my grinder at the same day I received the machine. I do a bit longer flush before extract first shot and do short flushes between extractions..

I believe you are trying to get too much out of the amount of coffee you are using. Try using the double basket in the single spout Portafilter and pay attention to the flow characteristics. When the flow goes "wiggly", stop immediately. Start with 24g of espresso from your 16g and SLOWLY work upwards as you desire.

If the coffee is fresh I'd grind a bit finer, and check the temperature But I'd start with Eric's advice of making shorter shots.