I passed it right after it happened when police and ambulance were in route. It was right under the bridge near Middlesex (I think that is the street) heading towards Kenmore.
There were a lof of cars and a few bikes there helping him out. The bike was at the curb with fluid on the ground. Looked like a car was involved.
Other than that couldn’t tell. But it was a grey and black sports bike with 2 letters on it like XR ???