so for this customer we only sold him the group so he could upgrade an older machine; this is his story:
Here’s a bit of evaluation. I’m comparing the output of my machine to the way it was with the original bezzera lever group. (It’s old, much older than the Strega, but looks very similar if not identical to the Strega’s group.)
With the old group there was always some injustice going on in the cup. Only rarely did I get the taste I was after. On the rare occasions that I did, it seemed more luck than skill. Often harsh and a bit sour, even when using beans that really shouldn’t have much acidity. So I ended up making milky drinks most of the time.
Damn, what a difference a lever group makes… With the new group it’s right on the money. Every single time.
Surely the Bezzera engineers did a very decent job on the thermal design of the machine. Measuring with a rapid-reaction, high-precision, ultra-thin probe inside the puck the temperature is always nearly perfectly flat (down to 0.1 degrees) during extraction (assuming a proper pre-infusion). (Yes, it messes up the extraction a fair bit, but it’s nice to know the temperature profile during extraction at the point of extraction.) But that didn’t change with the recent makeover.
Somehow the new group delivers the output much better. I’m getting silky smooth, rich, gentle and full-bodied espressos.
The paraphernalia I bought in the Londinium store recently (distribution thingy with funnel and the slightly deeper IMS baskets) help. The odd channeling shot that I experienced when I first started using the new group (much less often already than with the old Bezzera group) are now eliminated. Haven’t had one of those since. Kudos on the thingy’s design (and on deciding to make it in the first place).
Also, the Bezzera group had mechanical problems. Don’t know how it happened, but over time the piston rod would get bent. Not in the middle, but where the thick part transitions to the thread on the side of the lever. Never quite figured out how this happened. Longer ago I blamed the odd jaw-breaker manoeuvre (accidentally letting go of the lever without a loaded portafilter being in place). But the piston rod somehow always ended up scraping the sides of the hole in the guiding part on the top of the group, chafing off brass dust that ended up in the top the group. The new group is a different story. Such smooth action.
I won’t use the additional spring anytime soon. In the single spring setup the new group already requires a fair bit of additional force compared to the old one. Clearly the machine wasn’t designed to deal with that. It requires a special, gentle pulling technique to prevent the machine from toppling over forward. But with some minor practice it’s perfectly possible to pull the lever down while keeping the machine on all-fours. (Without having to push the front plate backward with my other hand.) I’d have to weigh the backside of the frame down with a block of tungsten or nail it down to the counter or something if I ever add the second spring.
So in summarising it’s fair to say that I’m very happy with the makeover. Very happy indeed. Thanks again for helping out.
For this roast we settled on a 20g dose with 1.8 bar of pre-infusion pressure
13s until the first drip fell in the cup and then an extraction rate of 1g/s until we had 30g in the cup after 30s more had passed - 10s pre-infusion would be your target, achieved by tamping with slightly less pressure
These darker roasts get really ugly if you run the shot too long - they are more soluble than the lighter modern roasts so they give up their goodness with less water being driven through the puck - if you keep going you get really knotty over-extracted notes appearing in the cup and you dilute the body in the cup too
The card that came with the coffee said a brew weight of 37-39g, but then we realised that these were just generic instructions for espresso extraction, rather than specific instructions for this roast
Once we realised that we cut the shot weight to 30g and everything sang
Very happy with where we got to here and in reflection i wished i had tried cutting the Epic shorter to a conventional 3g brew weight too as i think it would taste a lot better - it just isnt roasted light enough to carry the extraction to 38g
On request we purchased a 12oz bag of 49th Parallel Coffee roasters 'Epic' roast to try on our machines and discover our favourite extraction recipe
The coffee is supplied with a very informative brew card, as shown in the image above
After churning through the entire 12oz spread over two days of sampling we settled on the following recipe
Roast date: 28 November
Testing: 8, 9 December
Pre-infusion pressure: 2.0 bar
Pre-infusion duration: about 15 seconds to the first drip falling, timed from when the pump first turned off after the lever was pulled down
Brew weight: 38g of espresso flowing into the cup in 38s from the time the lever is released (i.e. excluding the pre-infusion time)
Note: the sweetness referred to on the supplied brew card does not present itself until the coffee begins to cool
i ran a number of iterations at a higher dose and pre-infusion pressure with the grinder eased a bit in the pursuit of more body, but for this coffee it didnt really work; the increases to the body are very incremental relative to the increases in dose and pre-infusion pressure and the tradeoff if the taste of the coffee just becomes too intense so i bailed out of that and reverted to the lower 20g dose and 2.0 bar pre-infusion - to do that we would have needed to increase the brew weight and then you end up with quite a different drink from what the roasters envisaged when they set the roast profile
I want you to know my LR made its way through US customs and I received it yesterday evening. Everything was perfect save for two scratches on the drip tray — I’m going to try some jeweler’s polish to see if I can buff them out.
I pulled my first shots this morning, and they were exquisite. I am exceedingly impressed with the design, fit, finish, and quality of espresso the LR produces. Thank you for designing and building such a great product!
I’m really looking forward to the wireless module and app availability.
Sent from my iPhone; please excuse brevity and/or errors.
better late than never, but we are making some good progress on getting this out to you finally
i think we are still on track to get the first of these out the door this month
the hardware is ready, and has been for a few weeks now
we are now at the point where we will print the housings for the wireless module and put the finishing touches on the look and feel of the app screen
the release of this module will allow you to finally experience the full capability of the LR, where you can mode it from a dark roast to an ultra light nordic or a filter roast in a couple of seconds and back again
it takes your LR ownership experience to a whole new level
this means we remain on target to launch the wireless module and app this month
the wireless module is a simple plug in to the serial port on your pressure transducer
in line with our previous commitment we will supply the wireless module and app free, the only provisio i will add is that it is provided free with any parts order of any value. in other words, you pay for the shipping and we will send you the module and access to the app free
i appreciate the support of all the customers that have purchased an LR prior to the wireless connectivity being available, and i never envisaged delays of the extent that we have had in realising this functionality
i will update you again as soon as we get to the next step
*in case you are wondering it also works perfectly with the panels in place too
i often get asked this question, so the bullet points below should help
- using a thermosiphon and heat exchanger design with variable pre-infusion pressure means that you are able to drastically shift the brew temperature profile without changing the amount of heat in the system: this ensures you do not push the system out of equilibrium (i.e. you preserve the thermal stability of the system; no flushing or thermometers on the group to manually force the system to a non equlibrium temperature)
- with the londinium system you can pull a 'hot shot' immediately followed by a 'cool shot' and then back to a 'hot shot', or vice-versa, as we are not changing the temperature of the group in order to deliver a different brew profile. This is a significant point of difference
- we control the pressure in the pre-infusion circuit rather than the temperature because it is more accurate. for example, wherever you measure pressure in a boiler you will obtain the same value whether you measure high, low, left, or right in the boiler
- if you measure temperature in a boiler, regardless of how precise a PID you use, you will obtain a different temperature reading in every different location you place the temperature measuring device in the boiler. for example, the temperature at the bottom of a boiler might be 85C; at the top of the same boiler it might be close to 130C
- in addition to the stratification of temperature in the boiler, you have thermal turbulence in the boiler and throughout the system, so you will observe constantly changing temperatures at any given point that you place the PID due to the turbulent nature of water when it is heated
- you can observe this thermal turbulence at work in your electric jug/kettle by placing a single droplet of food colouring in and watching how it is carried by the thermal currents in the jug/kettle: the same thing occurs in an espresso machine. for this reason we measure pressure, not temperature, as it produces significantly more accurate regulation of the system
- higher pre-infusion pressure gives vastly more body and mouth feel to the shot
- variable pre-infusion pressure results in variable shot volume. this works in harmony as lighter roasts are less soluble so we increase the pre-infusion pressure which elevates body, lifts the brew temperature and pushes more water through the puck to improve the extraction. shot volumes of 60g or greater are achieved at the higher pre-infusion pressures
- a londinium espresso machine it is designed to be optimised to run any coffee from traditional dark oily italian roasts right through to ultra light nordic roasts that have barely been breathed on by the roaster
- filter roasts can also be turned into pleasing espresso at high pre-infusion pressures: this is a range of versatility that is simply not available on other lever machines, and indeed one of the reasons for their decline in popularity
- a thermosiphon and heat exchanger design ensures that the system does not become hotter and hotter when consecutive shots are pulled, something that is unavoidable with the more common dipper design where the group is mounted directly on the side of the boiler; the result of this is that the boiler is constantly supplying heat to the group
- with a thermosiphon the group is kept at the correct temperature by water flowing by the force of the thermosiphon in a circuit from the heat exchanger (where the water is heated by the boiler) out to and through the group (where it cools) and returns back to the heat exchanger to be heated again. with a thermosiphon design each time a shot is pulled water rushes up both thermosiphon pipes, killing off the flow in the thermosiphon. the rush of hot water up both pipes from the heat exchanger to the group produces a brief lift in group temperature, but then it quickly eases back again as the thermosiphon flow has been interrupted. when a temperature differential is restored between the two thermosiphon pipes the thermosiphon begines to flow again and the group temperature is maintained. this is a very simple yet highly effective system as it maintaines the group at the correct idle temperature if a coffee is not pulled for a considerable period of time, yet if consecutive coffees need to be pulled indefinitely the group will not become hotter and hotter with each subsequent shot
- a PID added to a dipper configuration is unable to dump heat from the group quickly enough as the group is mounted directly on the side of the boiler so altering the boiler pressure only produces a small movement in temperature
- lever machines are all we do
- most manufacturers view lever machines as a quaint relic from the past and keep them in their product range merely as a sunset product as long as their customer base continue to buy them. any product changes are focused on stripping cost out of the build, which eventually compromises the user experience and so it becomes a self-fulfilling prophecy; lever machines are rubbish they cry
- we only use DHL Express. they have never lost a consignment. we have not experienced any machine damage since we redesigned our chassis in 2013
- we have successfully delivered and support our machines in 64 countries, a number which continues to climb
- any warranty claims are also met using DHL Express at our cost: we do not send them using a less expensive postal service
- we have all parts in stock
- we run high powered heating elements for rapid steam recovery times - divide the power rating (KW) of our heating elements by the boiler volume (L) to calculate the KW/L value for our machines and compare it with the competiiton
- the factory that produces our machines only closes at the christmas - new year period for about 7 working days
- we have an advanced website that provides multi-currency pricing that updates several times an hour and a very rich owners support forum
- we provide on going support free of charge including high definition video calls using Facetime and WhatsApp
- no one has ever got 'stuck' with a machine that they are uanble to fix
- we provide a 12 month worldwide parts warranty
- our machines have been designed from the ground up to be as reliable as possible, and in the event that something does break or require servicing that they are easy to work on
- no special tools are needed to work on our machines
- they are very forgiving for anyone who has never operated an espresso machine before
- all pipes on our machines are machine shaped and cut precisely to the correct length - many espresso machines have pipes that are hand shaped and cut
- all panel edges are deburred on our machines
- all our machines offer tool free access with pop off panels
- all our machines are mass produced so build quality is consistenly high
having said all of the above our machines are not for everyone. if you are looking for a machine where if anything goes wrong you want to be able to call a number and a service agent arrives at your door, then we are not the right choice for you
conversely, if you have suffered the indignity of having an espresso machine out of use for weeks, and in some cases months, as a result the parts you need not being held in your country and you are comfortable using basic hand tools then we are the perfect fit for your needs
if you are a cafe you can significantly reduce the total cost of ownership of your espresso machines, reducing downtime (with respect to both the number of instances and the duration of each instance) and avoid costly service and maintenance contracts
- as a one-off quirk of BREXIT our products are currently very affordable if you are purchasing in a currency other than GBP. i would invite you to revisit our pricing as even since last week the GBP has weakened significantly
- i consider the GBP to be significantly oversold, so i would encourage you to evaluate this opportunity as i think it may be fairly short lived. in any event, if it stays at current levels for an extended period of time it will eventually flow through to higher input costs for us and the GBP price will have to rise, so strike while the iron is hot
i am selling the Mahlkonig EK43S that i purchased new this year for the sole purpose of benchmarking the Kafatek Max against
happy to meet the market on price
buyer needs to collect
all original packaging and documentation present
feel free to bring your favourite beans along and test it on our LR before deciding if you want to proceed
this grinder has had less than 500g of coffee through it