the first "crash" on a streetbike was on my first streetbike. '86 VF500 Interceptor. Funny thing is that I wasn't quite to the street yet. It was riding across my parents front lawn making my way around the parked cars to the street from the garage.
I used to shoot across the grass and jump the curb... Well, this time I went across the roots of the big oak tree at a 45 degree angle. Some of these roots were as big as small tree trunks and stuck out of the ground 6+ inches.
On this occasion the front wheel made it over fine (doing 20mph-ish?), but the rear wheel just didn't go over, it just deflected and turned the whole rear of the bike sideways and SLAMMED me on the ground so fast I didn't even know what happened..... One of those falls where you actually FEEL the "THUD" in your head/body... Like a nice Motocross crash.
Even though it was only 20MPH and in the front yard,

I still count this as my first street wreck because of how violent it was and the fact I learned to be more mindful of what my tires were doing.
That was the only time I dropped my first bike. My friend on the other hand crashed it twice in one day.... Trashing everything cosmetic.