Dear Sir or Madam,
You are going on a group ride. That means that you know when it is planned and that there will be other people on said ride. You know that the general format for these types of rides that includes pacelines. You know that in any given paceline there is likely to be someone in front of you and someone behind you.
Recognizing these facts, I think it would be in everyone's best interest if you followed some simple rules. First, wash your clothes and make sure the ones you are wearing are clean. Second, wash yourself - there is really no excuse for this, not even if you are French. When in Rome, do as the Romans, and when in America take a shower with soap and warm water. Third, if you can't do this, at least have the common courtesy/decency to roll on a little deodorant.
I know what you're trying to do. I know you believe there is nothing that instills the feeling of riding in Le Tour de France quite like being in a paceline behind a person who is clearly trying to emulate their favorite French rider. That being said, it is one of life's more unpleasant experiences to paceline behind someone who smells like they're rolling along with an army of elves grating onions underneath one's kit.
Please commit yourself to the aforementioned guidelines before our next club ride. Thank you in advance for your cooperation. Thank you.