All,
After having to adjust chain tension daily, I decided to replace with a brand new 520 roller chain. I am still having to retention it one a day. Anyone else seen this? any ideas?
Alan

Don't overtighten it and inspect the sprockets for wear.

Jon

Maybe your chain adjusters are slipping. Check the tightness of the clamp bolts.

Also, after your next adjustment, try making a reference mark on the eccentric adjuster and the clamp with a magic marker or crayon, and see if the adjuster position changes over time. If it moves, then the clamps are not tightened. I had problems with a couple of the clamp bolts cross-threading in the aluminum housing, which made them really difficult to tighten and loosen. If you have the same problem, you should have the clamp threads drilled out and heli-coiled.

Also, if you didn't replace your front and rear sprockets when you replaced the chain, you are probably stretching the chain because of sprocket wear.