??

The oil tubes on the MC28 are press-fit into the carb outlet, not screwed. The tubes are bent at an angle. The 5mm threaded holes on the exact opposite sides of the carb outlets are normally plugged with a very small screw with an aluminum washer. Those holes are for carb syncing.

Does that help?
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Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
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