Car every time. You just can't compare a 10k bike and a 10k car because a car is so much more in every way - you're paying for 5x the materials to begin with! A better comparison for out and out performance would be to take a bike with unlimited funding to create the ultimate race bike and a car with unlimited funding to create the ultimate race car.... Funnily enough they exist - Grand Prix cars and bikes. F1 cars are MUCH faster than the moto GP bikes - why? Traction. Getting the power down in an F1 car you've got 2 huge rear tyres with loads of grip. On a Bike you've got a tiny patch and you've got to contend with the front wheel coming off the ground. In the corners again you've got a much larger contact patch on the car - along with downforce, and on a bike you can't simply change direction - you've got to get onto the other side of the bike and lean the whole bike in - it takes a lot longer. "In 2004, Mr V Rossi lapped the Sepang circuit in qualifying for the Malaysian Grand Prix in the very quick time of 2:01 (dry), that’s 2 mins and 1 sec. In the same year a Mr M Schumacher lapped the same circuit in the death defying time of 1 minute and 33seconds. This is a full 75% of the time a motorcycle takes. Or put another way; a F1 car can do 4 laps in the time a MotoGP cycles can do only 3. " With regards to acceleration - http://www.youtube.com/watch?v=mn6eHg1VSZI Road car vs road bike - http://www.youtube.com/watch?v=5_JsA1DgDhU Cars are also fast at top speeds, ref Thrust SSC Cars are faster accelerators, ref drag racing. Cars are faster round circuits, ref F1 v MotoGP times On top of all that, when it rains you remin dry, when its cold you remain warm, when you're bored you turn on the radio, when you're hot you turn on the a/c and when you blow away that TVR at the trafficlight grand prix you've got a passenger to silence the non believers.