That unit has one of the original Tanashin mechanisms, amazing that in all these years the design, placement of the pulleys and flywheel, the motor and even the placement if the plastic tape detector switch are all exactly the same as in a modern Sony CD-S70 that uses a Tanashin clone. I'd bet if you ordered a belt kit for the Sony it would fit this mechanism perfectly.
I guess it worked to a degree, and it would be cheap and easy - with pressed steel and some plastic moulded parts. Funny thing though, I tried raiding my RC 660 and 440 spares units amongst others - very similar, but all a bit different. Annoying as you'll see in part 2. Spoiler alert - I've had better days 😃
It's a bit onerous to be honest. I keep meaning to do it and then I look at all the files 😂That being said, it genuinely won't be too far away, because I'm working through editing my outstanding stuff lately 👍 I also have another TRK-8080 that should be simpler - teardown, deck service, switch clean and a scrub.