Sram Apex gear shifters adjustment

clickrumble

The front and back shifters are extremely stiff when going up to larger cogs/wheels, does anyone know what adjustment/lube is necessary? Bike is fairly new and has been like it since purchased. It's an internet purchase so taking it back isn't really an option.

cycleclinic

Look at the cable routing is there a sharp bend anywhere?

Remove cable from anchors. Do both mech move through the full range to enage those gears without issue. With the cable unachored can the shifters pull the cable through the housing easily?

checking all these things will find the problem.