Hi, I bought a pocket scale to start measuring my dose and doing wdt. So i have a stock Silvia basket which they say is 16gms. I try 16gms and initially the shot looks superb.. it takes about 4 seconds to start, thick syrupy mouse tails appear, but after 10secs or so it all goes to crap with thick stream then watery. I examine the puck and it looks fine with no signs of channeling so I don't know what the deal is. If I grind finer or tamp harder the machine chokes. I just can't seem to get a 25sec pull on this thing, it is a 15sec nasty shot. I guess I will keep playing with dose, maybe 18gms? (coffee is fresh, roasted 3 days ago).

*update, ok made some adjustments. I tried 18gms and it near choked with 1 oz in 50 seconds. Tried 17.2 gms and i got a 22-25sec shot but just 1 oz.. Might try 17.5 gms and see if I can at least get a decent 1oz shot. hmm

It can be some channeling, it can be too high of a dose (but 16g seems really fair to me), It can be too hard of a tamp.

basically what's your machine is doing is finding the weakest link in your puck because it's too tight and the coffee can't be infuse slowly.

Keep the dose constant and adjust the grind. Once you are close, then vary the dose and adjust grind accordingly to experiment with the most important judgment factor being taste.

Keep tamp moderate as it's easier to be consistent.

'Coffee roasted 3 days ago' is no guarantee that the coffee is suitable for espresso unless that same coffee pulls great shots in a quality cafe.

Additionally, many great professionally roasted espresso coffees are not at their best until days 5,6,7,8...

Thanks guys, I managed to get a solid 1oz good looking extraction but it tastes horrible. Even though I have reset my silvia to like 8.5-9bar and have a PID I am easily making the worst espresso in the world (I wonder if there is an award for that). I suspect I have no flippin idea what my temp should be set to.. even though the PID says 105 it's not 105 that is just what the top of the boiler is, so can anyone advise what type of device I can use to read temp out of the group so once and for all I can know what to set my PID to? When my PID is on 105 steam is frothing out of the head yet some guys were telling me to set it at 109c.

A bottomless portafilter would make a big difference in helping to diagnose your extraction issues.

well checked my brew pressure and it was ok. I ran through more shots this morning going on someone stating 'do not dose more than 14gms in a stock silvia basket' -that was a total catastrophe.. i tried 5 different grind settings and tamping pressures and all i got was pucs so watery they stuck to the shower screen or looked like soup in the basket. I keep saying I am going to throw in the towel and get a home trainer to come by but have been putting it off due to finances. Looks like I'll have to bite the bullet because either I am completely hopeless or something is wrong with my kit, but nothing comes out of this thing other than nastiness. Even considering selling it and giving up on espresso all together.. i mean some people simply can't hit a golf ball straight no matter how much they practice so maybe the same is with espresso, some people just can't do it :/

I've seen some Rocky grinders that can't grind fine enough for espresso. The symptoms are exactly as described

Have you checked burr zero?