Pneumatic Seal

I dropped down from the axle housing onto the inner alloy rim of the wheel. Two silver spokes framed a narrow corridor ahead. Rising between them was a threaded brass valve stem capped in black ribbed polymer. A primary seal guarding pneumatic pressure. I advanced along the curved channel, planted both boots wide, and clamped both fists around the cap. I applied controlled torque. The plastic yielded a quarter turn before locking rigid against the rubber collar. No hiss. Zero air escape detected. The pneumatic core maintains full integrity.