Personally, Jared, I think you could have just posted this in the earlier topic on Pterano.
Somehow, I imagine Rinkus's breath as being worse than Pterano's. While the LBT Pteranodons are depicted (incorrectly) as eating leaves and fruit (possibly in addition to fish, though even if this is the case, there could be some individuals who eat more of or only one or the other), we never get any indication of what Rinkus and Sierra eat. Their pointed teeth would not seem to indicate a herbivorous diet, though domeheads also have sharp teeth, and some have been seen to live in the Great Valley, so the teeth may have simply been added to the flyers' designs to make them appear more menacing. Sierra strongly resembles the carnivorous flyer that snagged Ducky in LBT V, and Rinkus is similar to long-tailed flyers that appear in other movies, such as two of the judges of the Day of the Flyers (who lack sharp teeth and thus could be as potentially flexible in their dietary habits as the Pteranodons). Unlike the LBT V flyer, Sierra seemed to have no interest in eating Ducky or any of the gang, suggesting instead that they be fed to the sharpteeth. However, this does not rule out fish as a possible diet for him or Rinkus, and given their dentition, I would assume that to be the case. At any rate, I'm getting off the subject. If Rinkus and Sierra are indeed non-herbivores, their diets would be restricted to fish, whereas Pterano has the option of feeding on less smelly fare. Furthermore, one might expect Pterano to be more concerned about what his breath smells like, given his vanity, whereas Rinkus and Sierra probably don't care too much. As far as how bad the rest of him would smell, your guess is as good as mine, though my argument for Pterano (a lack of skin glands equating to a lack of body odor) probably applies here too.
There is strong evidence that, like mammals and birds, pterosaurs were “warm-blooded”, producing their own body heat. They would need a large and constant supply of energy in order to fly vigorously, which a higher metabolism would be better at providing. Furthermore, fossil imprints show that many pterosaurs were covered in a coat of hair, a hallmark of animals that need to retain heat. Even ignoring the scientific evidence, the dinosaurs in LBT would have to be warm-blooded in order to remain active when the valley turned cold in LBT VIII. So yes, Rinkus probably would feel warm to the touch, as would any dinosaur or pterosaur in LBT. (The same might not be true for other creatures, such as Elsie, Mo, and especially Dil and Archie.)