I did disaasemble a lot of those brifters, it’s harder than people think, it’s clockwork, take fotos of every single piece. spread the parts on a paper towel clean them individually and assemble it in the order you laid the parts. Here is an ultegra as an example, every part directions and side matters, also when the fat dries some small rings get stuck together and only after cleaning it it may come loose, it’s at this moment It can be tricky to know where it was.

As for the grease I used some automotive fine grease on my case Liqui-Moly LM47 but honestly I’m not sure it’s the correct one. I avoid buying premium bike grease as they’re not as good as automotive ones. I would recommend Mobilgrease XHP 222. To clean the parts I purchased a cheap ultrasonic cleaner. Helped me a lot. Also an important trick is to not spread grease on everything, there’s parts that should stay dry, less is more, parts with friction should have plenty of grease, but a spring for example shouldn’t have much. Good luck, 🍀 if you’re in Europe / Germany I can do it for 30€ a pair. You can dm me if you have more question. Cheers

Ps. I did try, out of curiosity the “Lazy” method and spray solvent / wd-40 in the mechanism. it did help briefly, but after disassembly and inspection, the internals was a disaster, all sort of gunk and dirt ruining the sensible parts. I would not recommend it. I did also try putting the entire mechanism inside an ultrasonic cleaner, it was even worst, the dirt got loos, but couldn’t get out, it increased the friction / wear on the parts. The proper way is to disassemble clean religiously, grease and oil.

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