JohnB. wrote:I believe the Londinium's single spring max pressure is just a hair under 8 bar. My Bosco hits just over 8 bar max. My old dual spring Strega hit 11 bar & I definitely prefer the shots I get with an 8 bar spring lever.

I switched from a dual spring to a single spring because find it easier to add pressure if I want more than to retard the lever if I want less.

JohnB. wrote:I believe the Londinium's single spring max pressure is just a hair under 8 bar. My Bosco hits just over 8 bar max. My old dual spring Strega hit 11 bar & I definitely prefer the shots I get with an 8 bar spring lever.

I want to try both and judge for myself (I may like the 2 springs). I could remove the smaller spring and have that too. So many possibilities with this machine

Bosco is the godfather of that group head and the only machine that I had a hard time comparing to the Evo Leva. I always thought Londinium's peak pressure was 7.5! Thanks for confirming that for me

Why was a 54mm group selected? Wouldn't this "oddball" size make it difficult to get accessories? In particular tampers and filter baskets? Does the machine come with a 54mm tamper?

La San Marco creators of this group, Dalla Corte, and La Spaziale all utilize groups with basket size close to this one.

They are some of the most respected brands in Italy. My understanding is they choose this size range because it produces the best balance of Crema and flavor for their roasts. I can try to find the page Dalla Corte explains their reasoning for it.

I personally prefer it to a 58mm as I do get more Crema but also it is a bit more forgiving and easier to prepare a shot that does not channel particularly on a lever machine (these are my opinions on it others have mastered the 58mm and disagree with me, the 58 levers I have owned have produced amazing shots as well just a bit trickier). Plus it is easier to do single baskets and lower dosed baskets with smaller diameter groups..

I do think a double spring setup (11bar) on a 58mm would be more of a struggle, 7-9 bar not a problem due to depth of basket.

The only reason for the 58mm size proliferating is the ubiquitous E61 group by Faema becoming immensely popular because it was one of the first mass produced pump machines that was easy to use and service but most importantly had global distribution due to Faemas immense distribution network when it was released and as it grew in subsequent years.

In the last decade Chinese supply chains of accessories have ballooned the presence of 58mm accessories on the market that are easily accessible on Amazon and other sites. 15 years ago I would bet most of us on this forum didn't think 58mm was the only way to go on group size...we loved them all (even the 45mm +/- sized range like La Peppina and Caravel!!!).

Edit here u go one of the pages goes into more technical detail https://www.dallacorte.com/en/magazine- ... n-428.html

Dallah wrote:Why was a 54mm group selected? Wouldn't this "oddball" size make it difficult to get accessories? In particular tampers and filter baskets? Does the machine come with a 54mm tamper?

It's really quite common, as the group is used commercially. The Evo comes with an extensive range of accessories as standard 3 portafilters , single, double and bottomless, a tamper, 3 baskets and other accessories and spares, including the plumb in kit. If someone needs any more, they can purchase accessories at any espresso parts store.

Is this a puck shower screen from bplus/ flair58 on the top of the picture?

never used a Flair 58...it's a standard La San Marco shower screen....perhaps Flair use that screen, rather than the other way round

I actually meant this

https://www.bplus.biz/products/lower-sh ... uck-screen

I ordered this machine and I'm on the 2nd batch + I just received that bplus dispersion screen you just shared and plan to use it on this Evo Leva

The shower screen in @DaveC photo is the same in this video
http://www.youtube.com/watch?v=UZlH7MWLZkM

It's the La San Marco shower screen

Here is a picture of the group spares that I got with my ACS leva. Showing a clearer picture of the screen. Looks like I got a few more spares than DaveC