You’ll need to show the registration and insurance slip, else there is a charge for fail-to-provide this.
If you are covered under your own ontario auto insurance policy, if there was an incident, medical coverage and liability would come from your own policy, with collision coming from the owner’s policy.
The insurance company may not like this if you are living at the same address as the owner and are not listed on the policy, or if your use of the bike is a regular, frequent activity.