# Anyone running their Classic at 6 bar?



## J_Fo (Dec 24, 2017)

I've been thinking about doing this for a while but not got round to it yet, anyone else done it? Any reasons why it might not be a good idea?

Cheers ?


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## Inspector (Feb 23, 2017)

I have been using it at 6bar for a while. I am not sure if it is related to that but even i pull a shot for 50-60 seconds, it doesn't taste bitter at all.


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## J_Fo (Dec 24, 2017)

Inspector said:


> I have been using it at 6bar for a while. I am not sure if it is related to that but even i pull a shot for 50-60 seconds, it doesn't taste bitter at all.


 Thanks for the swift reply ?

I was wondering about that, I suppose if the pressure is set at 6 then it would take a little longer to pull than if it was at 9..? That seems to make sense but I have no understanding of pressure/flow so just complete guess work!

Gladto hear it's not been problematic, I'll try and do mine this weekend...


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## L&R (Mar 8, 2018)

Try 7 - 7.5 bar instead, very sweet results here.

BR


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## Inspector (Feb 23, 2017)

Mine is 6 bar dynamic. On pressure gauge i read 7 bar.

@L&R Do you.mean to adjust it to 7-7.5 bar dynamic? 8-8.5 bar on gauge.


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## MrShades (Jul 29, 2009)

You may well find that if you use 6 bar you actually need to grind finer. Higher pressure doesn't necessarily mean higher flow.

Anyway - 6 bar is great - I loved doing 6 bar pours on my Classic with dimmer mod, and 6 bar pours on my Decent are fantastic... it's the new 9.

Sent from my iPhone using Tapatalk


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## L&R (Mar 8, 2018)

Inspector said:


> Mine is 6 bar dynamic. On pressure gauge i read 7 bar.
> 
> @L&R Do you.mean to adjust it to 7-7.5 bar dynamic? 8-8.5 bar on gauge.


 Indeed


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## L&R (Mar 8, 2018)

High pressure means coarser grind


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## J_Fo (Dec 24, 2017)

Thanks for this guys, I'll change it this weekend


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## jaffro (Oct 6, 2015)

I could only get mine down to 8 on the gauge, so 7 dynamic, before mine kind of bottomed out.

It's great though, haven't at any point thought about changing back!


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## J_Fo (Dec 24, 2017)

Done!

Bang on 7 on the gauge on my 3rd adjustment... Just about to try it out.

Cheers guys


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## Marcros (Feb 9, 2020)

I have a classic, and a gauge that fits on the portafilter, but am confused about the gauge/dynamic discussion. what pressure do I need to adjust to on my portafilter?


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## J_Fo (Dec 24, 2017)

I just adjusted mine to 6 bar which showed up as 7 bar on the gauge. The gauge (on your portafilter) should read as one bar higher than the pressure you want to set to. I have no idea why though I'm afraid... But I'm sure a grown up will be along to explain. ?


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## Michael87 (Sep 20, 2019)

I think the 1 bar difference is for portafilter-mounted pressure gauges that stop the flow while you calibrate the OPV, like a backflush. As this is a static pressure since there is no flow. So this is typically a little higher than the pressure that would be "felt" by the beans.

When you have an in line pressure gauge that does not restrict flow it should give an accurate reading that doesn't need to be adjusted. As this is a dynamic pressure and the one "felt" by the beans.

Why? Because the flow of some liquid releases some pressure.

I think!


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## Pablo El Beano (Jun 15, 2019)

Now if a 6, turned out to be 9, I don't mind.


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## ting_tang (Jul 26, 2020)

jaffro said:


> I could only get mine down to 8 on the gauge, so 7 dynamic, before mine kind of bottomed out.
> 
> It's great though, haven't at any point thought about changing back!


 Have the same issue, any way to go lower or the OPV is limited?


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## jaffro (Oct 6, 2015)

ting_tang said:


> Have the same issue, any way to go lower or the OPV is limited?


 Not that I found.

I'm half way through refurbing the classic at the moment, having upgraded.

The OPV ended up pretty seized up. I'm struggling to loosen it, so it could just be that it was too stiff before. I'll see what I can do when I've sorted it...


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## ting_tang (Jul 26, 2020)

jaffro said:


> Not that I found.
> 
> I'm half way through refurbing the classic at the moment, having upgraded.
> 
> The OPV ended up pretty seized up. I'm struggling to loosen it, so it could just be that it was too stiff before. I'll see what I can do when I've sorted it...


 I was able to loose the OPV nut with a few drops of descaler. Left for 30 mins, and loosen it with tightening/loosening.


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## ting_tang (Jul 26, 2020)

found out, that at lower pressure need a longer brew time(45-50secs).

Read articles saying that temperature should be lowered as well, could you share your recipes please?


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## Nightrider_1uk (Apr 26, 2020)

Didn't Mr Shades do some spring kits that lower the pressure in the OPV?


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## allikat (Jan 27, 2020)

Nightrider_1uk said:


> Didn't Mr Shades do some spring kits that lower the pressure in the OPV?


 He does, but those are designed for the 2015 and later models as well as the low end machines that have a pump mounted OPV.


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## Vsutarov (Jan 5, 2021)

I would also like to know how much should temperature be lowered for 6bar.


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## MrShades (Jul 29, 2009)

ting_tang said:


> found out, that at lower pressure need a longer brew time(45-50secs).
> 
> Read articles saying that temperature should be lowered as well, could you share your recipes please?


 I'm not sure that either of these statements are true...

Regardless of pressure you should still be looking at extractions of 25-35s in general (a reduction in pressure does not mean a reduction in flow rate), and water temperature is water temperature regardless of pressure so anything in the range of 88-96c depending on bean and roast level


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## Mrboots2u (May 10, 2013)

ting_tang said:


> found out, that at lower pressure need a longer brew time(45-50secs).
> 
> Read articles saying that temperature should be lowered as well, could you share your recipes please?


 Errrr

That is not my experience , what articles are these you speak of


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## Vsutarov (Jan 5, 2021)

Maybe with preinfusion extraction time will be longer. Can someone share this kind of experience and if there are some rules?


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## Rob1 (Apr 9, 2015)

Vsutarov said:


> Maybe with preinfusion extraction time will be longer. Can someone share this kind of experience and if there are some rules?


 There's no pre-infusion from this mod, it's just a limit of the max pressure to 6 bar. There's pre-infusion in the sense it takes some amount of time for the puck to be saturated (when flow out of the puck starts pre-infusion ends, it doesn't matter what pressure that happens at). You can increase extraction time if you want, or not, it's not something really worth concerning yourself with, just use it as a rough guide to how much your grind setting has changed (e.g. an extra 5 seconds to get the same yield *on average (because a little variation between shots is normal)*). Extending pre-infusion from 5 seconds to 10 seconds isn't significant in terms of extraction time.

Pulling shots longer at lower pressures (higher flow rates) doesn't mean you *have* to lower temperature, but you could, just as you could as 9 bar if you think it would benefit the shot. Longer ratios don't mean longer shot times. I wouldn't expect benefits to increasing shot time at all, unless you control pre-infusion and spend a very long time with no flow i.e Rao's blooming espresso.


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## ting_tang (Jul 26, 2020)

Mrboots2u said:


> Errrr
> 
> That is not my experience , what articles are these you speak of


 This one for example. Also some threads in Reddit. I spent almost a whole bag trying to dial in with 6bar, but returned to 9bar and got a nice cup with a preinfusion opening the steam valve. Will give a chance to 6 bar later again.


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## Vsutarov (Jan 5, 2021)

I tried with adjusted static pressure 7-7.5bars. The taste is fine indeed. I dont have uniform extraction on open portafilter,had 3 than 2 streams,from some basket holes no liquid at all. If I suceed to get better extraction I know I will get better taste,but I dont know how.


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## ting_tang (Jul 26, 2020)

My main issue with 6bar was that I couldn't increase the body/bitterness, doesn't matter how finer I was grinding. Shots were sour/weak, tried a different yield. Beans were new for me and the result of my alterations was not as I expected. That's why I thought may be something related to the temperature or methods.


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## Mrboots2u (May 10, 2013)

ting_tang said:


> This one for example. Also some threads in Reddit. I spent almost a whole bag trying to dial in with 6bar, but returned to 9bar and got a nice cup with a preinfusion opening the steam valve. Will give a chance to 6 bar later again.


 If you are running a shot at 80c it will extract slower , or as a result of having to because of low pressure but because the temp is lower .


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## Mrboots2u (May 10, 2013)

Plus at 80c at that ratio the shot will be nominally under extra extracted I suspect . Doesn't mean thou cant enjoy the shot but at that temp at any pressure unles the coffee is super dark it's gonna be hard to extract the coffee .


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## ting_tang (Jul 26, 2020)

I agree, I tried with a different temperature as well, when I had a 6bar, 86/90/95 didn't make any difference. That beans are gone, but I have a well dialed in beans at the moment, will try them with 6bar.


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