There is a Smog Advisory for today, Thursday June 23rd.

You can check the current conditions at this Ontario Ministry of the Environment web site. The readings were good this morning at 8:00 am but that will change as the temperature increases. If the past few days the air got really bad by 3:00 pm so be off your bikes by then. get your riding in in the morning

There are spare the air actions that you can take. They are listed here.