E30 Zone

I've just changed the entire timing chain system on my 318is including sprockets, chain, guides, gaskets....

The engine runs fine, but i can hear a slight rubbing noise. Could it just be the new chain and guieds making some noise or should i suspect something else. I have driven the car for 5km and it's now a bit quieter. It's definetily not a mettalic rubbing noise, more like plastik or rubber.
Anyone experienced this?
Thanks!

when i did mine it was quiet on start up , may be nothing to worry about but if it was me i would take of the front cover and have a look . Better to spend a few hours checking it out now than have something let go in there . good luck