Being a relatively small 5.5" rim, fitting of these tyres is challenging for those without experience. The 200x85 measurements reflects the size when seated and inflated on the rim. If the hubs are wide, you will need high flow to inflate and form a seal on the bead.
The high velocity airflow for inflation usually requires a compressor (visit to the service station if you don't have an air cylinder compressor). Temporarily removing the valve from the stem also allows for more airflow.