We analyze a light curve of the symbiotic star BF Cyg , covering 114 years of its photometric history .
The star had a major outburst around the year 1894 .
Since then the mean optical brightness of the system is in steady decline , reaching only in the last few years its pre-outburst value .
Superposed on this general decline are some 6 less intense outbursts of 1-2 magnitude and duration of 2000-5000 days .
We find a cycle of 6376 days , or possibly twice this period , in the occurrence of these outbursts .
We suggest that the origin of the system outbursts is in some magnetic cycle in the outer layers of the giant star of the system , akin to the less intense 8000 days magnetic cycle of our Sun .
We further find , that in addition to its well known binary period of 757.3 days , BF Cyg possesses also another photometric period of 798.8 days .
This could be the rotation period of the giant star of the system .
If it is , the beat period of these two periodicities , 14580 days , is the rotation period of a tidal wave on the surface of the giant .
A 4th period of 4436 days , the beat period of the 14580 and the 6376 cycles is possibly also present in the LC .
We predict that BF Cyg will be at the peak of its next outburst around the month of May in the year 2007 .
The newly discovered 798.8 days period explains the disappearance of the orbital modulation at some epochs in the light curve .
The 757.3 oscillations will be damped again around the year 2013 .