I think younger birds for breeding (1-2) and 3-5 year olds for racing. I don't race old birds but I listen pretty good to the other guys. 
Some strains mature a little slower....but if you look at the National Champions in Europe, where they can end up competeing with tens of thousands of other birds, the age factor has been getting younger. IMHO, the "typical" National Champ is now under 3 years of age, and I also suspect, that is their prime breeding years also.Like all aspects of our sport, this next question I'd like to pose is, "What is considered to be a pigeon's prime?" For racing, for breeding?
B.Pigeon - This very interesting....why only Blue Bars? What makes them so different from other racing homers?For Blue bars when they start getting cocky..
i think it takes about 3-5 years for them to be
cocky...
i like the cocky birds..