My son didn't learn to ride a bike or swim until he was 11, although not for lack of opportunity or even interest. He had always had difficulties with motor coordination, and these tasks just took more than he had. He started doing horseback riding regularly when he was 10, and I think that that was probably the biggest factor in him finally developing the coordination to swim and ride a bike. Once he finally learned, practically the only way to get him off the bike was to get him into the pool.