So, my new bike has been tested a few times and it is a LOT quicker to ride than my old bike. Granted, you would hope that I would be fitter, but going from an average speed of about 12mph on certain roads up to 18mph is quite a jump.
Not something I can put down to pure fitness.
I would hope that I am fitter, but the skinny tires, slightly lighter frame, larger frame and new (slightly odd) gearing ratios have got to have helped.