These are a few few diffrent ways I would typically take a bike cross country from Toulouse to Barcelona - or return.
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The key is as follows:
The blue line is the one I would take that balances time with the ride.
The orange will save you time but has less good roads
The brown line goes through Andorra (for duty frees) takes longer/has better roads than the blue.
The red line is the one I would take - I would expect to make the journey in about 10 hours.
The motorway from Toulouse to Perpignan and down takes about 4-5 depending on the border delay.
The orange/blue line will take at least 6 hours
The brown about 8