Abstract: A quick-release hub retention device includes a pair of protrusions respectively provided on the outward surface of the lower end portion of each front fork leg, and a pair of rigid clips each pivotally mounted on the axle and having a curved free end for hooking over the protrusion to mount the hub on the front fork. The axle is received in the open-ended slots in lower ends of a bicycle's front fork legs in a known manner. Each clip includes parallel upper and lower portions extending radially of the axle, and a middle portion bridging the upper and lower portions of the clip and extending parallel to the longitudinal axis of the axle. The bridging portions are of a length so that the upper and lower portions respectively abut on the opposite surfaces of the lower end portions of the front fork legs. The clips are incorporated with a main retaining device to prevent accidental separation of the wheel from the fork even if the main retaining device on the axle becomes loose.

Abstract: A bicycle chainguard having a housing shaped to cover the top run of a bicycle chain with a curved forward end portion extending at least partially around a front sprocket. The housing has a pair of keyhole-shaped through-slots formed in a vertical wall. Clamps encircle seat and down tubes on the frame of the bicycle. Each clamp has a lug extending into a corresponding through-slot. Each lug has a shank with a diameter sized to fit within the through-slot, and an enlarged head sized to pass through an enlarged end portion of the keyhole-shaped through-slot. The longitudinal axis of each through-slot is oriented tranversely to the axis of the corresponding frame tube enabling assembly of the lug in the slot in a wide range of positions along the axial length of the through-slot to accommodate a range of angular orientations of the frame tubes for different model or style bicycles.

Abstract: A transmission mechanism with a novel crank and plastic-moulded gear comprising a crank member with a screw opening at one end and a larger head portion at another, and a transmission gear made of wear-resistant plastic material and incorporated with an inside gearing member through an injection moulding operation closely coupled with the head portion of the crank member so that the plastic-moulded transmission gear is always kept at its axis center without either wobbling or producing any noise during its rotation.