Wiring two post speakers with biwire cable

Craig (Garfish) is correct that bi-wiring makes little sense if your speakers have only one set of binding posts. The advantage of bi-wiring your speakers will NOT be realized unless the speaker has two internal crossovers to provide a separate signal to the mid/high frequency drivers, and another to the bass/low frequency driver. The two signals your amp will send to the speaker will simply be combined at the speaker's crossover. There is even a chance that you may degrade the sound, since using the set of bi-wires will simply increase the capacitance that the signal sees.

You guys need to read his question. He asked if he could use biwire cables on non biwire speakers. He does not intend to modify the speakers to biwire.

What you are proposing is called shotgunning and the results will tend toward a somewhat looser and fuller sound than a conventional single run of the same cables.It is normally used in tailoring a system to acquire a larger presentation.
You can alternately attach just a single set of connectors to the speaker end of the biwire pair for an interesting and educational experiment in capacitive loading.The sonic results will vary depending on your amplifier and the particular speakers being used.
As Aknorth stated, the unused ends should be securely taped over or fitted with wire caps to prevent an accidental short.

If your speaker cables are the same as the non-biwire versions you will not be shotgunning. Many brand of speaker wires are bi-wire capable. There are mulitple conductors (separate wires) per channel. All they do is segregate the separate conductors into 4 on the speaker end instead of 2. These type of cables will therefore be no different than the non biwire cables if used on your speakers.

1)Turnaround has a pair of biwire speaker cables, consisting of 2 sets of single wire cable in a common jacket
2) he intends to use half of the bi wire set to make a single run, either with an open ended ,unconnected pair on one set of speaker terminals or tying the separate pairs of runs together to form a single but doubled parallel pair
3)shotgunning simply involves runing 2 parallel identical runs to the speaker terminals
If he is using just a single pair run from this setup, he is using one half the number of strands, one half the amount of cable and in a configuration and topography with different load qualities including the added capacitance of the unused second run.
If he ties them all together at the speaker end ,he is effectively doubling the run in parallel.
Semantics aside, the results will still be a shotgun configuration if he ties both runs together.