After doing a bunch of T&E on my engine, I think I can conclude that I have a knock coming from my drive. Not sure where it is, I've read through all the posts, it goes in and out of gear perfectly, no performance issues at all, I will inspect upper unit, based on previous posts with same problem, I might need a new kit, how much of a chance am I taking running it until problem is resolved?

check your other post, like I put on the other post gimble bearing and dont take the chance and run it

silly question... do you have flappers inside your exhaust? They will make knocking noises and make you think you have an valvetrain or drive problem. Just thought I'd throw it out there!

If you don't want to take the drive off, maybe drain the oil and take the front cap off and inspect the teeth on the gears. If you lost a tooth on the gear it can have the same sound and the drive otherwise operates properly. If that's the case the next step is loosing another tooth, locking up the drive and son on and so forth.

Not something I'd be comfortable running it until I knew what it was.

Thats what mine did but by the time i heard it and shut it down the upper was done.. At first i thought the engine was knocking, when i figured out that it was the drive i almost felt relief.

DO NOT CHANCE IT.

Flappers, U joint, or Gimbal bearing most likely.

If it's a regular bravo I would check the teeth in the lower. Pull the plugs and look for evidence of the face of the gears losing a bit of material. Just went through this same scenario.

mine doing the samething had new ujoints and gimbel bearing put in and it still made the noise i took it out this week end ran all day fine the end of the day something came apart. got home pulled it a part and one of the ujoint caps came off. the housing where the gimmbel bearing seats just in front of it where there are lil peace of the housing broke off. will it be ok or do I need a nother housing can post pic.