A chain guide for a bicycle having may include a base frame and a height adjustment member connected to the base frame and slidable relative to the base frame and lockable in a first position by engaging a first locking member. A retaining member may be pivotally connected to the height adjustment member and may be pivotable about a pivot axis a retaining position, in which the retaining member is positioned to obstruct lateral movement of the chain away from the chainring thereby preventing lateral misalignment between the chain and the chainring, and a removal position, in which the retaining member does not obstruct lateral movement of the chain away from the base frame while the height adjustment member is locked in the first position. The pivot axis may be spaced apart from the first locking member.