Unless your snatching the clutch and pulling wheelies on a regular basis then the chain should settle down after a few initial adjustments.
It most definatly shouldn't have any tight spots.
I would get back in touch with your supplier. They may have supplied the correct pitch and size of chain but it may not be the correct tensile strength and will do just what you are describing.
My advice is get the chain off before it snaps and does some serious damage.
If you can, use the DID ZVM2. Its the best chain Ive used. I have one on my busa road bike and in 5000 miles Ive only adjusted it a couple of times. I also have one on the Turbo bike and that regularly sees the wrong side of 500 bph and has no tight spots after 2 years of use. (Its going to be changed for next season though) I bet that chain has seen the best part of 1000 miles. Not many miles, but the amount of abuse its had makes it quite impresive. Remember I launch at anything between 5000 - 10000 RPM and just let the clutch go.
I wouldnt use anything else.
