dockoelboto wrote:My only complaint with the mod is that now I look at the pressure gauge regularly during the brewing process and it is located in an inconvenient location. Especially for tall people.

Small price to pay for an otherwise enjoyable process.

I did a similar pressure profiling mod to my Linea mini as well, but I did not replace the stock pump. It was the the Gear Pump Mod from Titus. It took me about a day like you to install. It's been fun to play with pressure while brewing with the LMLM. My mod uses a Fluid'o'tech series geared pump. The pump is mounted on top with some modified piping and of course adding a couple electrical components. It is completely reversible as well. I had to reduce the pressure on my stock pump for the MOD. To control the pressure after moving the paddle I use a dial that is mounted on the side of the machine. I also installed a shot timer I got from ACE.

I've had to get used to looking at the pressure gauge during brewing but I don't mind it at all now.

Just curious. What is your minimum pre infuse pressure? I can't pre infuse any lower than about 2.5 bar. I find that that is slow enough for me, but I'd be interested to hear how yours works in that regard.

Was about to pull the trigger on the Grafikus mod, but now I need to reconsider. Can anyone break down the main differences in purpose/function? From my understanding, the needle valve with the Grafikus just allows pre-infusion and then full pressure, right? There's an "extension" now that lets the pressure gauge read the correct pressure as it brews--but is it still only the two options of pre-infusion pressure and then 9-bar? How exactly is the needle valve different from another machine that has pre-infusion? This (Rick's) mod is actual pressure profiling, correct?

The needle valve mods (Grafikus or Rick's) main goal is allowing for pre-infusion. The addition of the pre-infusion is the most bang for your buck on doing any mod. It allows for low pressure pre-infusion and then full pressure. You cannot profile the pressure otherwise.

The EMP Mod allows for complete control. Rick sent me this description:

This mod replaces the AC synchronous motor and pump with a variable speed brushless DC motor and specialized FluidoTech GA102 rotary pump head. The pump is controlled by a proportional signal generated by the paddle position so that as you move the paddle, pump speed and thus pressure at the group is constantly variable. This allows manual pressure profiling for each shot. Pressure control range is approx. 2 bar to 10 bar on tank operation. As well as potential for phenomenal improvement to cup quality, there is noticeable improvement in noise and vibration levels during brewing, low pump speeds are almost silent. This mod is best used in conjunction with the 0.6mm restrictor/gicleur, included in the kit. If this is already fitted, install time is reduced. All hardware and componentry is supplied, with pre-assembled, programmed, calibrated and tested electronic control board, wiring looms and component assemblies. The kit is essentially plug and play.

To me the biggest benefit of the mod is it is essentially an OEM mod and does not introduce any additional plastic or tubing of any kind. Plus it allows for full pressure profiling, you can pull a Londinium style shot on your LMLM. The needle valve mods are great and the guy I sold my needle valve mod to loves his. I just wanted to avoid additional plastic and wanted more control. Plus the machine is dramatically quieter.

That's really helpful. Thanks! Guess I need to start saving even more

Shawnaks5 wrote:I did a similar pressure profiling mod to my Linea mini as well, but I did not replace the stock pump. It was the the Gear Pump Mod from Titus. It took me about a day like you to install. It's been fun to play with pressure while brewing with the LMLM. My mod uses a Fluid'o'tech series geared pump. The pump is mounted on top with some modified piping and of course adding a couple electrical components. It is completely reversible as well. I had to reduce the pressure on my stock pump for the MOD. To control the pressure after moving the paddle I use a dial that is mounted on the side of the machine. I also installed a shot timer I got from ACE.

I've had to get used to looking at the pressure gauge during brewing but I don't mind it at all now.

Just curious. What is your minimum pre infuse pressure? I can't pre infuse any lower than about 2.5 bar. I find that that is slow enough for me, but I'd be interested to hear how yours works in that regard.

I'm using the tank. Realistically with the pump barely on, you can have incredibly low pre-infusion but realistically Rick claims 2 bar.

I reached out to Titus before learning about Rick - again, thanks @jettlag! Titus no longer does this mod, they only do grinders now. Your mod sounds very similar to mine. I guess the biggest differences are I had to remove the stock pump/motor but I didn't have to add or modify any piping. I control the pressure with the paddle, no additional dial required. The mod plugs into the stock location with some special brackets and of course the electrical components.

tglodjo wrote:That's really helpful. Thanks! Guess I need to start saving even more

The Grafikus mod is a great mod and many here are very happy with it. I figured why not go all in on the mod if I am going to do it at all. I'm very happy.

dockoelboto wrote:I'm using the tank. Realistically with the pump barely on, you can have incredibly low pre-infusion but realistically Rick claims 2 bar.

I reached out to Titus before learning about Rick - again, thanks @jettlag! Titus no longer does this mod, they only do grinders now. Your mod sounds very similar to mine. I guess the biggest differences are I had to remove the stock pump/motor but I didn't have to add or modify any piping. I control the pressure with the paddle, no additional dial required. The mod plugs into the stock location with some special brackets and of course the electrical components.

Thanks for the info! Seems like your installation was a touch easier than mine. It would be neat to see yours in operation. I'm curious as to how the pressure gauge reacts to your paddle movements. I wonder how it compares to mine. With mine, the dial is very sensitive to slight movements. Also it seems as if over time, the dial has gotten even more sensitive. Can you post a video?

The pressure gauge change and paddle movements are fairly linear. The initial movement of the paddle barely activates the pump but the more you move the paddle left you can hear the pump ramp up and thus pressure. It is easier to monitor during brewing. Without a blind basket or puck you can't monitor the pressure as closely. You can adjust the paddle to make the action lighter or tighter. That can help with the sensitivity. I imagine the operation is fairly similar, Titus is known for high quality.

I have a few videos but they aren't very good. One of them I have a kettle on the stove and it makes a terrible noise. I need to figure out a better video set-up. Plus I haven't uploaded them to youtube, I don't think you can directly add them on here, correct?

Yeah that all makes sense. I'd love to see yours in operation.

I think in the past I have added an icloud link here in HB for a video I made and it worked. I'm not sure if anything has changed since then though.

JettLag wrote:Basically, Rick had completed the GS3 version of the same mod

I did not realize this was available for the GS3!