The four stroke replica bikes come in all sizes starting at 250cc. The most popular size in Japan is the 400cc. The reason is that until recently, the Japanese were forced to take the test for over 400cc in a government regulated licensing office. There are very few such places and they do not operate on weekends so one needed to take time off school or work in order to take the test. The itself test was very difficult and most people failed a few times before they could get their license.

On top of this, the average Japanese people are small and it is difficult for a lot of people to use a big bike.

A change in the government policy resulted in a change in the law and now anyone can go to a riding school when they have the time for it, learn how to ride on a big bike and take in internal exam. It is expected that the population of riders who use bikes over 400cc will grow in the near future.

There are quite a few 250 and 400cc in the market but fewer bigger bikes. All in all the growing popularity of retro bikes and the massive exports from Japan caused a situation of less used machines in the market and less sales of brand new replica bikes.

Suzuki GSX-R 400 L	Honda CBR 400 RR-2
Kawasaki ZXR 400-1	Honda RVF 400