I seem to notice this on all my bikes. A crunching sensation through the pedals. Coming from the crank, chain or gears. Is this normal?
There isn't slack - it's under tension. Depending where you are you could have dirt or wear. Recently I bought a new bike in North Holland and I had a crunchy feeling within a few days. That area is exposed to wind and has very sandy soil. It was better after a lube. Most likely in your case it's a worn chain or dirty chain. Check for wear with a chain tool. Lube and wipe of excess with a rag.Not bearings. They are all new bikes. It must be caused by the chain slack being taken up as each cog enters a link.