So I'm trying to figure out what's going on. It all started one day at the track when going from a seated to standing position on the bike and my right knee had a sharp pain when bending it before getting ready for a jump. I thought something blew and almost couldn't bend my knee back (had to hold it straight out) as the pain was sharp and intense. I was ready to pull back in the pits, but the pain quickly subsided and I was able to get in some additional laps, but it was as if mhy knee wanted to lock about half-way into bending my knee. The point from seated to just starting to stand is where I felt the most discomfort, but it's sort of intermittent now. It's almost as if there's something between the knee socket that's giving this locking like sensation. Separate than being on the bike, occassionaly and without warning, I also experience almost a semi-locking sensation when going to a standing position either when seated or on the floor and you need to knees to get you up. I've read there could be potential fragments of something in my knee that could cause it to lock. Any ideas and how concerned should I be? I've also had knew x-rays in the last 2 years for other potential knee related concerns, but all were negative for anything.