[cpayton0]

So background I have a 07 ninja 250 with 6k miles. Was riding with some friends and when I took off from a u turn I hit redline and felt a slight pop, but didn't notice anything wrong. Pulled off into a restaurant and we ate when leaving I did it again hit redline this time it was clear there was an issue Because the bike wouldn't go passed 3k rpm without sounding like the engine was going to fly apart. pulled over check oil and was at low mark, filled oil smoothed out the knock a bit but still bad. Took it to a shop they said it's probably broken connecting rod or crankshaft but wanted 528 to take apart and another 528 to put back together plus whatever parts. So I took it home and started the work myself. But have no real idea what I'm looking at. I've rebuilt forks, carbs, calipers, and starters plenty of times as well as worked on my own timing and valves. So I'm sure I can do this just need some direction. Was told by a friend I'd have to replace pistons &rings and that should solve the issue but I want other opinions before I do anything also shop said they ran compression test and that it was fine but can't be sure they actually did it