I did have chrome res. covers and It felt like the rear and front locked up... got me, I've had several downs and it's always been my fault, wheelies and such.... With this bike Ive just been trying to be responsible and take it easy on the street so that this would never happen! It all happened in the blink of an eye..I still can't figure out exactly what happened. I will go to the tow yard and look over the bike to see if I can find the cause. I'm not really sure which tire locked up because it happened so fast, just bucked me off!
Man, don't beat on yourself. Sometimes, it's out of your control. Know firsthand.
Anyway, the way you are describing, the front locked. Here is why. Both can't lock at the same time. And if the rear locked you would be fishtailing for a good couple of seconds and would remember that. So, the only conclusion is the front locked, and I know firsthand it happens so fast.
Here is why I suspect the front locked, and here is why I asked you about the cromed reservoir cover. The stock cover, probably on every bike, has two small notches on the sides of the cover (where the cover comes in contact with reservoir) so the air can escape when the cover is in place. When the pressure builds up in the reservoir because of the heat, this is the only way it could escape. If you chromed the cover, there is a good chance the chrome covered those two small cutouts on the side. As a result, your cover effectively doesn't have those small vents.
What happens when the heat builds up and the pressure inside the reservoir grows, it has nowhere to go. So, this pressure is the same as if you are squeezing the brake lever. As the pressure builds up with no escape, so does the pressure of the pads squeezing the rotors. At some point, the pads squeeze the rotors so hard that they lock. I am suspecting that's what might've caused your get off.
Check the chromed cover, and see if you notice two small vent slots - one on each side of the cover (left and right). Compare to a stock cover if you have one. Was it a hot day when it happened? Was the bike parked in a cool place prior to the ride? If so, all of these factors would contribute.