[Anupam Goli]

There is no single blanket "best ratio" to use. It all depends on your strategy and what you want to do. Do you want to be quick? Do you want to have pushing power, but don't want to be necessarily quick? If you are using a single speed gearbox, you can look between 4.67:1 to 13:1. We ran an 8.46:1 ratio in a Toughbox mini. We got about 9 fps and we had decent pushing power. The toughbox might be a good starting point. The good thing about the toughbox is that you can just buy the gears and change the ratio based on your results. You can also adjust the ratio in the sprockets. Remember, the higher the ratio, the less speed you have, but the more torque you will have behind those wheels. Striking the balance is something you and your team have to figure out. If you search in the CD papers, you can find JVN's drivetrain calculator, which allows you to learn everything you want to about a drivetrain before you build it.