Yes this is normal. In fact, that's exactly what you want until it's broken in. It's caused by the cylinder tapering at the top of the piston throw, providing a leak-free compression seal. A word of caution, however, don't try to turn it over too much until it has been run and broken in. I even used a heat gun to warm up the cylinder just prior to it's first start. Break it in and it'll diminish and provide you with a great running engine.