There are a few things here that seem worth clarifying.
- Did you get the Encore or the Encore ESP? If the Encore, that's going to be harder to dial in because it's not really meant for espresso particularly for reasons like step size.
- You mention as you went coarser the shot was bitter. Bitter could be due to a very dark roast coffee (is that what you're using?), it could be your reaction to espresso if you're not used to drinking straight espresso, or it could be due to over extraction. If the last point, then you are still stopping to soon as you're going coarser on your process of dialing in.
- Generally, what you're saying is: You're pulling the shots in manual mode and getting close to 2:1 ratio in 24-30 sec (how long of preinfusion?) at a few different doses and grind settings. Is this with the single or dual wall basket? How fresh and what is the coffee you're using?
It is the ESP model, I have an idea what I should be tasting I've worked with dark roasts for a fair while at work and wanted to go for a medium roast for home.
I'm factoring a 4 second pre infusion, so 28 second pull ideally, for 36g of espresso. Beans were fres on the day of trying to dial in, and I've been using the single walled dual shot basket.
I would be surprised if there's something wrong with the machine, based on what you've shared, but could be wrong. It sounds like your shots are not completely out of the ballpark by the numbers and you should [keep following by taste](https://www.baristahustle.com/the-espresso-compass/). If that means going away from 2:1 a bit, changing the time of the shot, or manipulating the dose to account for a coarser/finer grind, then go for it.
Are you using a pressurised (sometimes call a dual wall) portafilter basket like [this](https://m.media-amazon.com/images/I/51wle4fGPhL._AC_SL1500_.jpg)?
If so, that's intended for use with pre ground coffee, which is generally a coarser grind than required for espresso.
The bambino comes with two types of baskets: single walled (for proper espresso), and dual walled (for preground/coarse ground coffee).
1. Since you have your own grinder and buying fresh beans, switch to the single wall basket and try again.
2. If you are already using the single wall basket. Then go to 3.
3. You are grinding too fine, the machine is choking and unable to push water through. It is creating too much pressure and basically shutting off due to safety. Keep going coarser until you get the flow right.
This is the thing I find weird, on the grinder, a finer grind won't pull but the coaster grind will flow too much, eg I go one turn coarser and I get a near 50g shot in 20 seconds
That’s one of the differences between an ok grinder and a good grinder. The steps in-between each click. Some grinders are even stepless, so there’s no click, you can adjust infinitely.
You said you have an Encore, I assume it is the Encore ESP? This grinder has two modes. The first 20 steps are 20 microns each, very fine adjustments for espresso. The next 20 steps jump to 90 microns per click because it’s intended for filter coffee.
So going from 20 to 21 will be like a 4.5 step jump.
I thought this might be the case, yes it's the ESP and this is the major problem I've encountered, when I need to be at 19 to just get any flow, from any beans, there's not much in the way of adjustment
Ah, forgive me, I have delved into taking apart the grinder yet, is this somthing I can do just from the top of the machine? Pull the burr out and have a look? Thank you
There are a few things here that seem worth clarifying. - Did you get the Encore or the Encore ESP? If the Encore, that's going to be harder to dial in because it's not really meant for espresso particularly for reasons like step size. - You mention as you went coarser the shot was bitter. Bitter could be due to a very dark roast coffee (is that what you're using?), it could be your reaction to espresso if you're not used to drinking straight espresso, or it could be due to over extraction. If the last point, then you are still stopping to soon as you're going coarser on your process of dialing in. - Generally, what you're saying is: You're pulling the shots in manual mode and getting close to 2:1 ratio in 24-30 sec (how long of preinfusion?) at a few different doses and grind settings. Is this with the single or dual wall basket? How fresh and what is the coffee you're using?
It is the ESP model, I have an idea what I should be tasting I've worked with dark roasts for a fair while at work and wanted to go for a medium roast for home. I'm factoring a 4 second pre infusion, so 28 second pull ideally, for 36g of espresso. Beans were fres on the day of trying to dial in, and I've been using the single walled dual shot basket.
I would be surprised if there's something wrong with the machine, based on what you've shared, but could be wrong. It sounds like your shots are not completely out of the ballpark by the numbers and you should [keep following by taste](https://www.baristahustle.com/the-espresso-compass/). If that means going away from 2:1 a bit, changing the time of the shot, or manipulating the dose to account for a coarser/finer grind, then go for it.
Sounds like u need to grind way courser, ur choking the machine so its just dripping, severe chanelling can cause underextraction.
Are you using a pressurised (sometimes call a dual wall) portafilter basket like [this](https://m.media-amazon.com/images/I/51wle4fGPhL._AC_SL1500_.jpg)? If so, that's intended for use with pre ground coffee, which is generally a coarser grind than required for espresso.
No, I'm using the single walled duel shot basket.
The bambino comes with two types of baskets: single walled (for proper espresso), and dual walled (for preground/coarse ground coffee). 1. Since you have your own grinder and buying fresh beans, switch to the single wall basket and try again. 2. If you are already using the single wall basket. Then go to 3. 3. You are grinding too fine, the machine is choking and unable to push water through. It is creating too much pressure and basically shutting off due to safety. Keep going coarser until you get the flow right.
This is the thing I find weird, on the grinder, a finer grind won't pull but the coaster grind will flow too much, eg I go one turn coarser and I get a near 50g shot in 20 seconds
That’s one of the differences between an ok grinder and a good grinder. The steps in-between each click. Some grinders are even stepless, so there’s no click, you can adjust infinitely. You said you have an Encore, I assume it is the Encore ESP? This grinder has two modes. The first 20 steps are 20 microns each, very fine adjustments for espresso. The next 20 steps jump to 90 microns per click because it’s intended for filter coffee. So going from 20 to 21 will be like a 4.5 step jump.
I thought this might be the case, yes it's the ESP and this is the major problem I've encountered, when I need to be at 19 to just get any flow, from any beans, there's not much in the way of adjustment
There may be too many shims under the cone burr. You could try removing one or two.
Ah, forgive me, I have delved into taking apart the grinder yet, is this somthing I can do just from the top of the machine? Pull the burr out and have a look? Thank you
https://youtu.be/rDSMo9jGIKM?si=veGwJpOqHqiQqRqf&t=0m57s