1977 used to have a decent blog, but it looks like it's offline now. There's a specific article I referenced years ago about Puch Polinis, oils, seizure, etc.
It was found here: https://www.1977mopeds.com/blog/2009/03/02/why-do-puch-polinis-seize/
Anyone know of an archived copy? I emailed 77 to ask, but no dice so far.