GDK wrote:I already asked and got a quick answer - they experimented while dialing at different RPMs and found the best results to be at the suggested numbers.

Based on my interactions with Option-O so far, I am quite impressed with their customer service!

Good to know how they got their results, which turns out to be the same way I arrived at my sweet spot RPM (at least for that one coffee I tried). I assume their testing was way more extensive than mine and probably with seasoned burrs as well.

I just installed this burr set. I switched from SSP HU burrs.

I just pulled 3 shots to try and dial in;

• 1st shot - I kept the grind setting about 1.4 away from zero which is close to what I used with HU. The grind looked pretty course and as expected the shot was way too fast.

• 2nd shot - I went closer to the recommended settings for light roast (0.5) This was still too fast but the shot tasted OK.

• 3rd shot - I went 0.2 away away from zero, which kinda had me nervous because I never had to grind this close to zero. It was still surprisingly quick but the shot had some sweetness I never experienced before with the HU.

So far I'm a bit worried I won't be able to grind finer than this but I'll experiment more tomorrow. I'm a bit too over-caffeinated now.

For reference, I'm using this bean currently https://zabcafe.com/collections/cafes/p ... -gathaithi
Going 14g in, ~31g out - RPM set to 6.

Update: I completely missed the shims they sent in the package. After installing those I can now grind fine enough for espresso. I'm actually having to go coarser than recommended now. Finally got a nice shot with the same coffee at about 1.2 notches from the zero.

If you haven't reset your zero point after the burr swap it might explain the large difference in grind settings before and after. If you've already recalibrated relative to the burrs just touching then maybe try updosing (your roaster recommends 18.5g in) and/or using a basket with more flow restriction.

I had already re calibrated. I just updated my post to give more information.

I'll update the thread after the burrs are a bit more seasons and I've tried more coffees!

What number is your new zero point? Given how close you are to the zero point, I am a bit suspicions that you may have the issue where current mizens are too thin for the second generation P64.

Correction: I just read your note about the shims that you forgot to install at first. Congrats! Keep the feedback coming.

What did you think of the level of clarity compared to the HU?

Has anyone received the non-shimmed version of these burrs yet? (or did people who previously purchased a P64 separately from the Mizen's receive them?)

I'm also having some issues with the Mizen for espresso. Mine came with them installed, so I haven't messed with it except to make sure the chirp point isn't way off. I gave up for the day cause I'm over-caffenated, but I'm at 0.25 and my shots are still way too fast, tho they're not as sour as I'd expect for 17.5g in, 42g out in 22 seconds.

BananaApple wrote:Has anyone received the non-shimmed version of these burrs yet? (or did people who previously purchased a P64 separately from the Mizen's receive them?)

I messaged Option-O and they are shipping end of the month (or trying to). Cafune in Canada has them but apparently they are the shimmed versions.

gongfugang wrote:I'm also having some issues with the Mizen for espresso. Mine came with them installed, so I haven't messed with it except to make sure the chirp point isn't way off. I gave up for the day cause I'm over-caffenated, but I'm at 0.25 and my shots are still way too fast, tho they're not as sour as I'd expect for 17.5g in, 42g out in 22 seconds.

I'm wondering if it's related to burr alignment. I know with the SSP cast V1's: they only were comfortable with espresso after shimming
May wanna dry marker test them