Hi Wise Peeps
I have a Rocket machine and I have never used any kind of lever machine. However as I got into this hobby, I really love the idea of making espresso.

I wanted to know from lever users..... can you easily manipulate the amount of pressure as you pull the level? If I had a pressure gauge (or one of those digital ones), will i be able to see different pressure through the pull, allowing a different profile of flavors?

I don't have a lever machine yet either, but I have an Odyssey Argos on order and am excited to learn to use it.

A direct manual lever, (as opposed to a spring lever), will allow you to feel resistance to the force you are applying as you pull a shot. That resistance is what generates the pressure. A gauge is helpful, although unnecessary, as you can pull by feel, altering the force applied to maintain fairly constant resistance and thus pressure through the shot.

You can use a gauge and follow along with pressure profiles, eg. Lance Hendrick with a Flair:

I have a Londinium Compressa. It's a plumb in only machine...more on that below. While it's easy to manipulate the pressure by retarding the rise of the lever during extraction, It doesn't have a brew pressure gauge, so it would require trial and error and practice. That said, I don't really see why one would want to do that.

On the Compressa, the early part of the extraction is a line level preinfusion (true for any plumbed spring lever), that can be down regulated from supplied city pressure with an adjustable valve (purchased separately). This also affects brew temperature, as one is changing the flow through the heat exchange tubing.

Londinium also makes a reservoir version called R24 that has a more user friendly app to regulate preinfusion.

There are also manual lever machines (without springs), where all of the extraction pressure is supplied by the barista. I think most of those have group pressure gauges, so one can see what they are doing and repeat it accurately and precisely. From what I've gathered from many manual lever users with years and years of experience, after a while the pressure gauge isn't used that much. They get used to the look of the extraction stream and the feel, such that they don't need the gauge. I have been using a Flair intermittently for several years, but I only use it for travel, and haven't quite broken free from looking at the gauge.

Iconicred wrote:I have a Rocket machine and I have never used any kind of lever machine.

Just to be sure we're clear, your profile lists the Rocket Appartamento, which is an E61 pump-driven espresso machine. It has a brew lever, but it's not a "lever" espresso machine in the sense that the brew pressure is determined by how much pressure is applied to a lever (or, another lever design, by a spring).

If you want to manipulate brew pressure with an E61, you can install a flow control device. It's essentially a needle valve that sits atop the group with a gauge so you can increase/decrease the pump's flow by moving a lever horizontally. Some E61 espresso machines come pre-configured with a flow control device (e.g., the Lelit Bianca); others have it as a separately installed part.

Back to your original question:

Iconicred wrote:I wanted to know from lever users..... can you easily manipulate the amount of pressure as you pull the level? If I had a pressure gauge (or one of those digital ones), will i be able to see different pressure through the pull, allowing a different profile of flavors?

Sure, you can do that. In fact, some levers like the Cafelat Robot optionally have a pressure gauge specifically for that purpose. But a lot of lever users just go by feel and observing the espresso flow versus studiously watching a gauge.

Thanks. Yes what I mean is that I am a novice user of a basic Rocket. I have have been interested in getting into Levers but never used one. I am just asking some basic basic questions to gather some more knowledge in the event that I get one

So with a spring lever the initial pull down is the pre infusion and then the spring takes over the actual release and extraction. If I understand that correctly, it means the the "barista" won't be able to manipulate that part of the process. But with a manual lever the barista can be in control of all of it.

So for a spring lever (as with a semi auto with NO flow control) the grind will determine the pressure profile. Did I get that roughly correct?

Iconicred wrote:Hi Wise Peeps
I have a Rocket machine and I have never used any kind of lever machine. However as I got into this hobby, I really love the idea of making espresso.

I wanted to know from lever users..... can you easily manipulate the amount of pressure as you pull the level? If I had a pressure gauge (or one of those digital ones), will i be able to see different pressure through the pull, allowing a different profile of flavors?

For a direct lever like my La Pavoni equipped with a pressure profiling kit (PPK), yes...it's easy to adjust group pressure on the fly. Spring levers are not my forte'...yet. So I'll defer to others in that regard.

With the La Pavoni, depending on which generation, GH temperature management tends to be the bigger challenge. But there are affordable mods for that too.

One of the many appeals of the Argos is its flexibility in morphing into a direct or spring lever within minutes. Also better temperature management. Also a comparatively low price compared to other established companies' levers.

I have a Profitec Pro 800 spring lever machine and a Strietman manual lever machine.
The taste of the espresso between the two machines is subtilty different.

Similar to some people liking different brands and roasts of beans, such is true of the espresso made by lever machines.
I had a Rocket E61 machine for close to a decade. I'll never go back to this type of technology.

Iconicred wrote:So with a spring lever the initial pull down is the pre infusion and then the spring takes over the actual release and extraction. If I understand that correctly, it means the the "barista" won't be able to manipulate that part of the process. But with a manual lever the barista can be in control of all of it.

So for a spring lever (as with a semi auto with NO flow control) the grind will determine the pressure profile. Did I get that roughly correct?

On a spring lever, you (usually) cannot extract at a higher pressure than the maximum pressure of the spring (and max. pressure only happens at the very beginning of extraction). However, a spring lever can always be retarded (held) with one's hand during the shot. Thus, you can manually lower pressure during a shot, but only the spring can increase pressure during a shot - you cannot manually increase pressure beyond what the spring can give at that point in its compression. (FWIW, I can't think of a situation where it is desirable to increase pressure during a shot.) Here's a famous video showing manual retard of a spring lever; skip to about 3:50 for the example (one of three videos, watch them all if you are looking into a commercial spring lever group) http://www.youtube.com/watch?v=T9OUNXVLY_o

If you do not manipulate the spring lever, then the spring determines the pressure profile. Just like in a pump machine, the grind size determines the rate of extraction at a given pressure; it does not determine the pressure being applied to the coffee puck (admittedly a bit of a chicken-egg thing here).

In general, pre-infusion is not a function of whether the lever has a spring or not. Pre-infusion in a lever typically starts when water starts flowing from the boiler or heat exchanger and stops once the lever is lifted (spring) or pushed down (manual).