Terraformed Venus, and its complications.

This is really a question, and it boils down to: If Venus were terraformed (or the terraforming was set in place), but human life on earth either died out, or was reduced to a point whereby they couln't colonise it.

The story I'm writing has it that intelligent life has formed on venus and has civilised the land.

The issue mainly lies in the fact that one of the key ways to make Venus a better place to support life (after fixing its atmosphere) would be its spin.

**The biggest question, is:**

**If we sped up Venus to an earth like rotational rate, at what speed would the rotation slow?**

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(Also appreciated would be input from others with earth-like worlds that lack tides, notes etc, and input from other users on what they think of the scenario!)