Help a newbie with sampling and bars

Ok I have a sample and chop it up to 5 seconds with soundforge. I open up recycle and set it to 4 bars. I open reason and add it to dr rex. I play it on my track and for the 4 bars 2 bars at the end have nothing. Why is this. Is tempo off? In dr rex it says tempo 177 my real tempo is 80 for the sequencer wtf