Went for a ride today. i was jumping out of a steep dugout and i was going verticle. once i was in the air i grabbed my brake to level out, all was good until i started hitting it harder. next thing i knew i landed and my track was stoped. opened (pried) the cover off and chain was broken, chain case exploded, and the bearing in pieces. i didn't land with the brake on, what do you think caused this. its a 03 f7 sp and i was only jumping about 5 ft in the air. could anyone tell me what its going to cost to fix or were i could find used parts