2000rpmで55km/hならば10000rpmで275ｋｍ/ｈですね。うむ。これが速度の限界か…。

Default Widget

This is Sidebar 1. You can edit the content that appears here by visiting your Widgets panel and modifying the current widgets in Sidebar 1. Or, if you want to be a true ninja, you can add your own content to this sidebar by using the appropriate hooks.