So i took the bike with me to find the cause of the problem. It seems as my muscular legs were making contact with the velcro straps on the regular size saddle pack. We switched to a mini pack and no more contact. I can still fit my 2tubes, tools, 2tire levers in the mini.
They also adjusted the chain free of charge.
Finding the right LBS before u buy a bike was the best advice that i got.