I have driven/camped the Canadian Rockies from Seattle to Alaska.* What the others said: stash all your food at night, either hang it from a tree or put it in a reinforced locker (where available) away from the tent, and have absolutely nothing in the tent with you (including sweets, snacks, some sites even advise against lip balm). Some of the campsites are very big and comfortable and the biggest threat is asphyxiation from the nightly mass-barbecue ritual, others are little more than a metal bucket and instructions to swill it out in the stream before returning it. My biggest concern about cycling would be making it to the next campsite every night. Some are very spaced out, man.
* That sounds rather grander than I intended, but grand it was.