Without seeing the beans i would have to blame the roast level for the problems ez...
The rolling second crack and extremely oily beans sound like you took them a little bit too far into second crack.
Often beans like this will be superb for a day or two before going south.
The reason for this is...the more you roast into second crack the more the cell walls start to break down and release the natural oils inside the bean. Sometimes it takes a day or 2 before these oils make there way to the outside of the bean with the degassing process.
From this point onwards the coffee will act very unusual and probably start to taste and smell a little bit like an extinguished camp fire.
Try roasting just into second crack and then look at updosing your basket instead of roasting darker. Sour notes should only come from either underextracting your shots or from lighter roasts. With these lighter roasts its often acidity that is confused with sourness.Originally Posted by 4B545C4F424743432E0 link=1270344414/0#0 date=1270344414
Sounds like you need to do some more roasting ezralimm ;)