Hi.

Ive read a review on coffeegeek and came across this: https://www.coffeegeek.com/reviews/comm ... Wilco/2511 What is this restricted water he is talking about to make ristretto fans love this machine or is it just bs ?

Wilco Bos wrote:So I learned that some distributors, like René, adapt their espressomachines to the local taste. That means long espresso's, so to say: a bit trendy brew of strong coffee in a big bowl. Yuck!!! That adaption concerns the insert of a "floodgate" in the waterchannel of the head, resulting in a decreasing pre-infusion time; within the normal carry on through time the amount of water increases. After undoing the modification to my Super by René, the problem was solved and the making of real ristretto's is possible again (one sip a cup).

I wonder is the discussion revolves around the flow restrictor in the thermosyphon pipe...? It is located in the upper pipe at the boiler end. other than that I do not know what effect that would have. Could it be the Gicleur in the top of the group? I am just guessing.

There are some inaccuracies in that CG review... For example, the size of the boiler has little to do with brew temperature stability other than to overcome poor design. For example, the relatively tiny, dedicated brew boiler of the Vibiemme DD has remarkable brew temperature stability.

And how can the use of a plumbed rotary pump instead of a vibratory pump allow one to grind "much finer" as described in the article? Only if the pressure is greater. Why not just set the OPV higher with the vibrator pump?

I believe that the thermosyphon size is changed by some importers to regulate the flow to avoid overheating of the group and thus limit cooling flush times, but beyond that someone with more knowledge of the machines than I will have to figure out this one.