Which statement about V-belt position in the groove is true?

• A. It should ride high in the groove with the top near the top of the sheave
• B. It should ride centered in the groove
• C. It should ride near the bottom of the groove
• D. It should touch the bottom of the groove only at start-up

Answer: (A)

In a V-belt drive, the belt is shaped to wedge into the groove of the pulley. When seating the belt, the best practice is for it to ride high in the groove so the belt’s top surface sits near the top of the sheave. This position allows the belt’s sides to press firmly against the groove walls, producing the wedge action that translates tension into grip and ensures efficient torque transfer. It also helps the belt wrap properly around the pulley and keeps it tracking centered under load, reducing the chance of side-to-side walk.

If the belt sits lower in the groove, it can bottom out on the groove base, which reduces effective wrap, increases wear on the belt and groove, and makes tracking less reliable. Riding centered might still function, but it doesn’t maximize the side-wall contact and wedge effect as effectively as the higher seating. Touching the bottom only at start-up would indicate improper seating and would not sustain proper engagement once the system is running.

So, riding high in the groove with the top near the top of the sheave best promotes correct engagement, grip, and tracking for a V-belt drive.