Bonnet closing procedure as people are reporting dents! The Type-R bonnet is made of aluminium, pressing on the bonnet to close it can cause dents or distortion, so the correct procedure should be used when closing the bonnet. 1. Remove the support rod and stow it in the clamp. 2. Lower the bonnet to approximately 30 cm from closed and then remove your hand to let the bonnet drop to close it.