how to spot fake parts?

i have been sorting my mountains of tomy BPT over the last week, and during the sort, closer inspection of parts has revealed quite a bit that was lacking the tomy logo. some are stamped made in china, others say thailand.

does every single geunine tomy piece say 'tomy" on it, or could it be logical quite a bit got missed? i am not just talking about tracks, but also the yellow girders/risers and the step risers as well. and its all types of tracks, from straights and curves to the A/B riser curves, stop tracks and points. even some half straights.

also, i found some track that didnt have the "lines" on the track, but more like a rough surface. some other had the lines, but very faintly done. both types are stamped as made in japan. i am keeping these for now, as i wonder if they are early plarail, like from the time of the push along range.

best find was a number of quarter length male/female adapters with tomy on one side and plarail on the other. i know they have been discussed here before, but its been a while since i have seen them