Toro Grandstand Bogs down intermittently during use

[AThornton81]

I have a 52" Toro Grandstand with 385 hours on it. Over the weekend I noticed that the deck bogs down intermittently during use. I maintain properties weekly, so the grass doesn't get too high to too thick. It'll bog down for 30-45 seconds, and then come back full speed. Any guesses as to what the cause may be? Once I can get home, I will take a video and upload it.

 

[mechanic mark]

Post year, model & serial numbers as well as all numbers from engine & engine manufacturer.

 

[exotion]

Belt slipping? Not tight enough