A tubeless tire inflated to 140 psi requires slippage marks?

• A. Yes, slippage marks are required
• B. No, tubeless tires never require marks
• C. Yes, only if rated above 150 psi
• D. No, marks are not required for tubeless tires

Answer: (A)

Bead slippage during inflation is something you actively check for on high-pressure tubeless aircraft tires. Slippage marks are placed on the tire and on the wheel in aligned positions so you can see if the bead moves relative to the rim as pressure rises. If the marks stay aligned, the bead seating is okay; if they slide and become misaligned, you must stop, deflate, and reseat the tire before continuing. Because 140 psi is a high inflation pressure, marks are required to verify that the bead hasn’t slipped and seating is secure. The other statements are not correct because slippage marks are used to detect bead movement at high pressures, not that tubeless tires never require marks or only above 150 psi.