This I can agree with. But that's rather the point of the honours system. He's done more for the country (even if it's just to give a bit of pride to the followers of cycling) than some of the crooked MPs and business folk who get titles for chucking money at political parties to help keep the tax laws nice and vague. I could go on.
Essentially the gripe you have is against the system, which I'm happy to go along with. Perhaps it is too early for Cav to get an award. Perhaps his award should come for taking the green jersey to Paris. However, when footballers get awards for winning nothing for their country we should probably just congratulate him and target our ire at the system rather than the people it rewards.
AIUI the system works its way up the Honours for sustained contribution. So if he continues to do well he may well get upgraded in another 5 years to an OBE, CBE or Knighthood.