Ditch the single basket and read this thread.
All you need to know
I've recently purchased a Barista Express BES870. I'm happy with the results I've been getting thus far but have a few things I'd like to try and get right. Overall, I'm currently having a problem with the size of my shots and the extraction time. From the manual, the goal appears to be:
Flow starts after: 4-7 seconds
Extraction takes: 25-35 seconds
Shot size: 30ml
I've run a few tests to try and get it right but not having much luck.
Details of the tests are as follows:
Whole Beans: Bills Beans - Mr Smooth. Roasted on 29/7/14 (today is 23/8/14). From my knowledge these are good quality beans.
Filter: Single filter basket that came with the machine. Picture below:
Filter size selection: Single
Cup selection: 1 cup
Machine is warm before starting.
Puck is trimmed with the included dose trimming tool.
Results are below (when I list numbers for Dose and Pressure, it is where they are showing on the manual gauge with reference to a clock face). As you can see, none of the conditions I've tested so far are giving me even close to the required shot size. I can get the total extraction time in the 25-35 second range..but only if I grind very fine and get a small shot. I realise I have not tried every variable but any help would be appreciated.
Test Grind Dose Tamp Flow starts after (seconds) Total time (seconds) Pressure ml 1 No coffee in basket, test with water 42 2 2 1 Med 12 35 2 4 3 7 11 Med 10 25 1 9 4 9 Min Med 8 20 1 21 5 10 Min Soft 8 17 11 22 6 10 Min Hard 8 18 12 22