Rocket R58 - Pre-infusion

Need help with equipment usage or want to share your latest discovery?

#1: Post by Brazilianhipster »

Dear all,

I've recently purchased a Rocket R CINQUANTOTTO [R58], after 'attempting' to learn the basics on a Sage Dual Boiler! I won't be plumbing it in but will rely on the water tank.

My question is on pre-infusion

From reading various articles on this forum, I am under the impression that when the lever is fully lifted up to engage the pump, a degree of pre-infusion will occur automatically? Is this correct?. If so, roughly how long does this pre-infusion period last for?

Fully appreciating that there are no hard and fast timings, but at least to get me into the right 'ballpark', should this pre-infusion time be included in the total extraction time? Or should I add a bit of time on to the desired extraction time?

I understand the lever can also be lifted (without engaging the pump) to allow 'pre-wetting' (if using the water tank), again, is this correct?

If I start manually playing around using this technique, is there an approximate guideline in terms of time e.g. allow pre-wetting for x - x seconds before engaging the pump?

Thank you for bearing with me! A basic understanding will then allow me to really experiment! :D

User avatar
Team HB

#2: Post by another_jim »

On E61 groups, the middle postion of the lever opens the water path without engaging the pump. If you are plumbed in and have a rotary pump, you will get water flowing at line pressure. Since you are using a tank; this won't happen for you.

When you lift the lever all the way, you also engage the pump via a button on the front panel pushed by the lever's external cam. At this point, the water flows into the group, including cylinder with a spring loaded piston. This device gives you a gradual ramp up in pressure. Instead of reaching full brewing pressure in 4 to 5 seconds, it takes around 8 seconds. This makes it easier to get shots without channeling, and improves the extraction sightly.

There are after market needle valves you can install in the group that will allow you to control the flow and pressure on your machine manually during the shot by turning a paddle. I would recommend this if you like lighter roasts, since it will allow you to grind finer and greatly improve the extraction of these often hard to extract roasts.

You can get all the details by googling the posts within this site.
Jim Schulman


#3: Post by hnrqbarcelos »

I own a R58 v2 and have recently discovered that there is a solenoid in the beginning of the mains water path that only opens up when the pump is turned on. So even plumbed in you won't experience pre-infusion (my case). I believe R Cinquantotto has the same design as far as I have researched.

There are some workarounds to make it happen if you're really wanting to put in the work such as removing the plunger of the solenoid, or removing the solenoid altogheter and putting a check valve in place or wiring the solenoid directly so you can open it up at your discretion. I personally gave up because I'm terrified of ruining something inside of the machine.

As Jim pointed out, there are some Flow Control Valves that will enable flow profiling, so you can PI and much more without such a hassle