knocking/slapping noise

[peabrain]

yesterday i noticed my bike has a loud knocking/..rattleing slaping kind of noise.

when i rev the engine it is fine the engine sounds sweet and happy, but when i out it in gear and rev it still happy engine. But when i take off and put some load on the engine it starts making the noise, it is loud is it only present during load milder load makes it quieter.
when decelerating the sound is not there, all the gears work fine and it shifts with out a problem.

(the sound is mostly noticeable during lower speeds)

[SK Racing]

It will help if you can post a video with sound.

[peabrain]

will try and look for my MIC and something to record on.

[herennow]

look up the videos on cam walk noise. If it is that it's no problem.

[peabrain]

Update
Adjusted the chain and put some cardboard on the rubber stop on the center stand and the sound id mostly gone.

i think the chain is shot and also the front sprocket, has very much side play and has some bad links.
So i ordered a DID Z link chain with a JT pair of STD sprockets.

i am also getting some new springs for the center stand and side stand as they are kinda weak and very crusty. (will include the rubber stop since it is very hard and old)

[peabrain]

After putting on a new chain kit the noise was gone.

my guess is a part of the reason for the noise was due to the center of the old one was bad.