Tomorrow is the launch of Robert Penn’s new book about his pursuit to create his ultimate dream bike. Admit it, this is something we all want to do one day, so we asked him to tell us why he wrote his book.

Robert Penn is the author of It’s All About the Bike: the Pursuit of Happiness on Two Wheels, published by Particular Books on Thursday.

Lance Armstrong was wrong. I realise this is rich – telling the winner of the Tour de France a record seven times that the title of his best-selling book is erroneous – but there you go. I’ve done it now. Lance, you don’t know what you’re talking about. It is about the bike.

Rob Penn - It's all about the bike

Lance and I ride for different reasons, of course. He rides to be one of the best athletes on the planet. I ride to skip bath time with my kids. I also ride to get to work, sometimes for work, to keep fit, to bathe in air and sunshine, to go shopping, to escape when the world is breaking my balls, to travel, to stay sane, for a moment of grace, for fun, occasionally to impress someone, to scare myself and to hear my boy laugh. It’s a broad church of practical, physical and emotional reasons with one unifying thing. It’s all about the bike.

Rob Penn - It's all about the bike

The bicycle is one of mankind’s greatest inventions – it’s up there with the printing press, the electric motor, the telephone, penicillin and the World Wide Web. I’ve ridden one most days of my adult life, in over 40 countries on five continents. In my late 20s, I gave up a career as a solicitor and cycled 40,000km around the world. When I’m old, I’ll still ride a bike to the pub. I’m in the middle of a lifelong love affair with this simple machine. Yet, two years ago, none of the hard-working bikes in my shed even hinted at my devotion to the bicycle. Something fundamental was missing. Like tens of thousands of everyday cyclists with utilitarian machines, I recognised there was a glaring hole, a cavernous space for something special – my dream bike.

Rob Penn - It's all about the bike

I knew where to start – a steel frame made by Brian Rourke, the renowned British frame-builder. From there, I travelled to Marin County, California (where I rode the Repack trail with Charlie Kelly and Joe Breeze, the mountain bike pioneers) to have a pair of wheels handmade by Steve ‘Gravy’ Gravenites. At the Cinelli factory in Milan, I bought the bar and stem, and at Campagnolo, I purchased a Record ‘gruppo’. The tyres came from Continental in Germany and the saddle was handmade at Brooks in Birmingham. The bike is the loveliest thing I’ve ever owned. Now – what does your dream bike look like?

Robert Penn is the author of It’s All About the Bike: the Pursuit of Happiness on Two Wheels, published by Particular Books on Thursday.

Rob Penn - It's all about the bike

His TV documentary, Ride of My Life: the Story of the Bicycle will be broadcast on Tuesday night, BBC Four, 9pm. If you feel like commenting on the documentary, or on the coverage bikes get on the BBC in general: http://www.bbc.co.uk/bbcfour/yoursay/

You can WIN a signed copy of the book, just leave a comment with how far you have gone to build your perfect bike! The competition ends by the end of the week.