Question: 12 miles bike long does take?
Answer: If you mean in what time you should complete 10 miles as a beginner, I would say for children this may take two hours (including stops), for a slow adult an hour (no stops calculated), for a good pace that doesn't leave you out of breath (12-15 mph) 40 to 50 minutes, and for a top speed (15-25 mph) (40 minutes or ...