I own a TX750 for 7 years now. Great bike despite of the horror stories everybody and their dog will tell you. And, you won't find a bike with less vibrations from early 70-ties. Of course, there are issues with engine design. In fact, most of them were caused by Yamaha accountants rather than by engineers. Once you hold the very first and extremely rare japanese parts book in your hands, you will be surprised about the components an engine should have you never saw in it - balancer and starter chain tensioners, additional magnetic/centrifugal oil filter, different crankcase breather incl. PCV valve, case internal paper oil filter, oil sump mesh filter unit etc. I'd hold the engineers liable for a single significant problem - engine heat management. It just runs too hot when ridden hard.
Then, every single TX750 engine, early or late, has a built in design flaw. There is a collar few mm too long blocking an oil passage.
To manage the situation with failed engines back then, Yamaha first went with bolt-on parts rather than engine re-design. The latter happened little late in second production year (1973) while update kits were available for early engines. In fact, those bolt-on parts like deep oil sumps etc. are almost useless. Also, Yamaha didn't use the majority of them on their late style re-designed engines. As goes to significant changes, late engines differ in 3 things: oil routing (early engine cases could be updated), max oil pressure went up from 20 psi to 55 psi and balancer chain got a tensioner again. Once those "teething problems" are solved and with high mileage, you will discover a whole lot of other tiny things you ever even heard of. With little knowledge and basic mechanical skills, few hand tools, oil cooler kit plus few hundreds in parts thrown into late style engine, you can build a motor that will do 100.000 mls easily without major issues.
Another great thing, as the TX750 being underrated, its parts are cheap compared to Kawi Triples.
_________________ 2x 69" H1
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