Throttle Controls & Grips for Harley Big Twin Motorcycles. The Big Twin Throttles & Grips collection at TC Bros is crafted for riders who want enhanced control, comfort, and style for their Harley-Davidson Big Twin motorcycles. This category features a range of high-quality grips, throttle assemblies, and cables designed for durability and smooth performance. Compatible with models like Softails, Dynas, and Touring bikes, these components are perfect for custom builds or factory upgrades. With ergonomic designs, precision engineering, and a focus on rider comfort, TC Bros throttles and grips deliver a superior riding experience while adding a bold, custom touch to your handlebars.