We derive new solutions for the binary black hole model of OJ287, using the November 2005 outburst as one of the fixed points. Previous models have used the September 1994 outburst which is in many ways ill-defined, and leads to considerable uncertainty in the orbit. The parameters of the system to be determined are the orbital period, fixed by the separation of the 1947.30 and 1983.00 outbursts, the orientation of the major axis of the orbit at a given time, fixed by the 1972.97 outburst, the time delay factor which is a function of the disk thickness, fixed by the 2005.76 outburst, and the precession rate of the binary, fixed by the 1913.00 outburst. A unique solution is found for the case of gravitational radiation and of no gravitational radiation. The 2007 September outburst begins 2007-70 (September 13, + or - a few days) in the former model, and at the beginning of October in the latter model. The three weeks difference will be easily resolved in observations, and thus the emission of gravitational radiation can be indirectly measured. X-ray observations support the idea that the 2005 outburst is related to an impact of a secondary black hole on the accretion disk of a massive primary.