Samoeng Loop in a car - July

My Girlfriend has (sensibly) barred me from renting a scooter while we're on holiday in CM. However, we still want to do the Samoeng Loop on our last day in CM. Leaving after breakfast and returning to the Airport before flying out late at 8:00pm

Is it safe enough to do? I'm a confident driver, never had any crashes etc. I have an IDP and full license in my home country.

Any advice would be great!