My bike I'm working on now has a twist grip on both sides. Cables run inside the bars and exit down through an oval hole I had milled in the center. Throttle on the right and front brake on the left. I'll be using an autoclutch. They're identical, so the left twists forward. Very high quality and expensive units. Each has six ball bearings. Smooth operation and clean looking. I'm going for a lean, simple look.