Hi Terence 573,

I don't have a KG89 but just quickly reviewing a couple of YouTubes on the matter appear to propose the same thing, being to reset the adjustment so the steps can go finer. These mods don't appear to be destructive in that you can easily reverse the setting if you end up not liking what you get.

So go for whichever you feel most confident in executing.

Worst case scenario is the whole thing blows apart and you'll have a good reason to upgrade!

Any hologram tape preventing you from opening the grinder up? If none you can always rewind any mod should there be any reason to utilise the warranty. Anyways for the most part grinders are quite sturdy. Since you are into espresso, you'll probably be avoiding the lighter roasts with harder beans.

Seriously consider manual grinders that can meet espresso requirements for your next upgrade.

I'm guessing the hand grinders you are using have ceramic burrs. These do take a lot of time. However, steel burr hand grinders are significantly faster. Typically around 120 revolutions will prep a 15g dose for espresso. About 50 seconds.

Lots these days, and most are quite easily accessible if you are ok to order online.

Let's see:
From the Western hemisphere
- Kinu (M47, Traveller, Phoenix)
- Commandante
- Lido E

From China
- 1Zpresso (so many models I'm completely confused) - I use the Pro
- ACE48
- Timemore
- Anonymous

For this quadrant of the galaxy, the China premium grinders give very high value for money. Under RM 400 delivered would get you quality espresso grounds.

I totally understand the struggle of manual grinders! But yeah, there are many pros too--like longevity (I think I've gone thru 2 electric grinders now and my manual grinder is still as sturdy as ever). Also, I get too conscious about cleaning it up, because there could be molds hiding deep within the parts. For manual ones it's easier to take them apart and clean the parts while for electric... it's a complex matter. But I try anyway, coz I didn't want the quality (and safety) of my coffee to suffer. I seriously suggest "deep cleaning" the grinder regularly (a simple cleaning procedure I follow is in here: https://coffeforus.com/howto-clean-coffee-grinder/)

Recently I tried started to feel that im getting headaches whenever I dont drink coffee on the morning or for a longer period of time. Did some research on the net and stumbled upon this article on negative caffeine effects https://coffeforus.com/negative-caffeine-effects/. Decided to quit coffee for some time to see if I can break the habit.

Kg89 is not the standard measure of quality... it's for ppl with cheap hotel room coffee percolator

Ask our friend few post back where he got this grinder

Should be cheap and good enough... this should have the trespade burrs...

One step up will be the mignon everyone is buying here

Gemilai CRM 3605.

Stock setup the cons as below:
1. Thermoblock system might not able to keep the temperature stable.
2. Weak steam.
3. OPV not set to 9 bar and release the excess water flow to drip tray. In fact, safety valve would not open at 15 bar which is the max pressure generated by ULKA pump.
4. Flow rate too high. Recommendation is around 200-280ml / 30 seconds. I measure around 360-400ml / 30 second. Indirectly causing the pressure too high.
5. Single thermoblock machine. Can't brew and steam at the same time. If you only make a cup each time, then it's not a big issue. Only take less than 10 seconds heat up to steam temperature. If you want to brew second cup, just purge hot water from steam wand for 5s and temp will drop to brew temperature.

How to overcome the issue.

By heating up the water in the tank to 50 degree celcius (get this idea from Decent Espresso machine), I manage to solve issue 1 and 2. No more sourness in espresso and steam is more powerful and dryer. I heat up the water tank by running hot water from the steam wand for 30 second, then pour the hot water back into the water tank. Do this 3 times and it should be around 50 degree celcius (only when the tank is full).
As for pressure and flow rate, I install a solid state variable resistor to control the pump. Doing this I manage to control the pressure for pre infusion and ramp up the pressure to 9 bar when I see first drip of espresso from the bottom of the naked portafilter. By using lower pressure during pre infusion and let the puck fully saturated will reduce channeling issue.

Overall, I'm quite happy with the machine performance after mod. Temp control with PID and using standard 58mm portafilter, you can get lots of accessories for the machine. Also build in pressure gauge and brew timer (user changeable) which make it quite a good entry level machine.

CRM3605 is using PID stock. No mod needed on the temperature sensor unlike some other machine which is using analog thermostat. You just need to pre heat the water tank to around 50 degree celcius so that the thermoblock have more headroom to stabilize the temperature during brewing. Another advantage is more powerful steam when steaming milk.

The only mod you need to do is the pump. If you unscrew the bottom, you will see the connection for the pump. You just need to unplug the wire from the circuit board to the pump, tap the pump to the 500w dimmer switch or solid state regulator. I'm using solid state regulator with 100k ohm potentiometer. When brewing, turn the knob almost to the minimum. As I'm using bottomless portafilter, the pre-infusion take around 10 seconds and will saturate the puck. Turn the knob to increase the flow while watching the pressure gauge. Once it reach 9 bar, stop there and continue to extract. You can play around with the pressure during brewing process. One of my favourite method is to slowly ramp down the pressure to around 6 bar before reaching my desire extraction weight.

PS: Ignore the red switch. Previously use the red switch to manually switch on the heater for old Poemia espresso machine. Not use in Gemilai. The potentiometer come with the solid state regulator resistance is too high and at minimum will stall the pump.
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