P was injured when he lost control of his motorcycle after striking debris in the road. P was wearing a helmet manufactured by D. P was incapacitated by his injuries, and his natural father and guardian brought this action. P sued D alleging that the helmet was defectively designed and manufactured and that D failed to warn that the helmet would not afford any significant protection from certain reasonably foreseeable impacts. P offered deposition testimony from an expert that not motorcycle helmet provides assurance of protection from facial or brain injury at speeds of 30-45 mph and that the average purchaser would not know these facts. A summary judgment was given D and P appealed but only on the failure to warn issue. P appealed.