They are fundamentally different machines
The pump on L1 is not pumping water into the group, it is only driven in with the head of pressure in the boiler and the extraction is only achieved with the force of the spring, in the traditional manner
We understand that there is only one significant manufacturer of lever groups remaining in Europe, which by implication means the world. The way it works is the bottom half of the group is common to a number of different models offered by this manufacturer, then you get to increase the performance of the group by choosing which ‘top half’ you want to bolt on
The ‘top half’ of the group on Londinium I is the same as both Bosco and Kees van der Westen’s Idrocompresso have now upgraded to, and the Quickmill Achille. It costs a full 50% more than the ‘standard’ top half with the external bearings.
Why the additional cost? It has internal bearings so no unsightly group cap is required to stop users getting their hands caught under the bearings. To ‘internalise’ the bearings the top of the group needs to get a lot bigger, so you need a lot more brass. It also runs on a different cam profile which does clever things to the pressure profile.
After that you get to play around with different springs, including the addition of a second spring if you wish, which also has a big impact on the taste
Londinium I sits on a cleverly engineered chassis which you won’t find any added ballast in, nor holes for fixing it to the deck
Londinium I is not a hybrid trying to be all things to all people
If we could eliminate the pump from Londinium I we would. For reasons set out in a previous post this is not possible
We believe the most effective way to maintain the optimum temperature in the group when it is idle is with the addition of a thermosiphon. The magnificence of physics means it circulates on its own without the need for any electrical complexity; there is nothing to fail
We think the old ways are often the best ways. Londinium I seeks to extract more performance by refining the old ways
The spark that fired the Londinium I project was to build a machine with which it is easy to consistently achieve optimal extraction
If people want to make comparisons then look to the machines that we have had a long involvement with. We consider the taste of the Bosco to be significantly superior to that of the Cremina. To be fair, why wouldn’t it be as it is a full fat commercial machine, whereas the Cremina is an incredibly compact lever group for the home
Londinium I will meet or exceed (in some areas) the build quality of the Olympia Cremina whilst achieving the taste definition of the Bosco