There's a lot of power to be made when you can rev to 13-16k RPM.
There's not nearly the same kind of torque you have with a big car engine but then again, the bike does not need it so the trade-off is OK.
If you could feasibly rev a 2JZ engine to something like 13k-16k, you could make a lot of power for the displacement you have available. But you would have to sacrifice torque and your engine would be built with some serious unobtanium parts. Of course, the physics of that are not possible for mass produced machines.
Bikes can do it because the piston speed is slower. Compared to a 2J, a 600cc bike's stroke is almost half. Do the piston speed calculations at a typical bike RPM. Let's say 13k.
2JZ: 86 mm stroke = 122.3 feet/sec
600RR: 42.5 mm stroke = 60.4 feet/sec
1000RR: 55.1 mm stroke = 78.3 feet/sec
To get a 2J down to similar piston speeds, you have to bring it down to around 7500RPM (70.5 feet/sec), which is of course a typical limit most people rev their engines to. At their respective RPM limits, a 600cc engine, a 1000cc engine, and a 2JZ are all in the same ball park of piston speeds. So in other words, they are working with the best that physics and materials used allow but the bikes have close to twice the RPM with which to make power.
I don't pretend to be an engineer and understand all the dynamics of safe operating limits and I don't know figures for typical max safe piston speeds but you see what I'm getting at. I'm sure there are many other important factors like important head design. Also, don't forget that we're talking about sport bikes which are tuned and built very strong, power wise, as they are from the factory. Bikes generally do not see the same gains you would see in a car from basic mods. Consider that even for sports cars, they are not as race focused as a sport bike (unless we're talking exotics and then even still). With a sport bike, you get an engine that is pretty peaky (compared to maybe a more standard motorcycle) in an effort to make max power, light weight relative to other bikes, suspension adjustability you would pay thousands of dollars for in a car, and tires that are more performance oriented than you would find on a car. The kind of performance and race track manners you get from a bike off the showroom floor, you would have to spend a lot of money on a car.
So, in these ways, bikes are very advanced technologically and mechanically speaking. In other ways, cars have been ahead of bikes for years and still are. I'm talking about things like engine management and other electronics. Sport bikes only started using electronic fuel injection systems in the early 2000s. ABS, Traction control, and other electronic aids are the new wave in sport bikes right now. How long have cars had these things been commonplace in cars?
It's a lot of apples to oranges, really.
