The treads might be funky in a grooved road or over a steel bridge but as long as the tires are of the same construction you should be okay. They really need to both be bias or both be bias-belted and not a mix to get good results. I've run Dunlop up front and Kenda in back on a heavier bike and it handled okay, it was much better with a matched set but those were also Avons and that might be the bigger factor.
