Mackenzie on acquiring throttle control
Riding god, Niall Mackenzie, imparts his wisdom on mastering the twist of the wrist
The smaller the bike, the easier it is to practice opening the throttle mid-corner because there's not as much power and delivery is softer. It's always going to be a bit risky with high revs and low gears however many CCs, so to avoid a highside stay in a higher gear - you can open the throttle with more confidence and safety, though obviously you're not going to be as fast.
I grew up with two-strokes. Riders brought up them gain good throttle control because there's not as direct a connection between throttle and wheel as with four-strokes - especially modern fuel injected ones that carburate smoothly. With two-strokes, you open the throttle and half a second later something happens, especially if they're not jetted properly.
Practice by getting used to your bike's power and delivery by launching it off the line. Next, get to a smooth corner, one that you know, and go through it with a partial throttle to see what happens. Then open it a bit to see what happens, and close it a bit to see what happens. Try riding round the corner in different gears and at different RPM to see how the engine behaves. Practise opening and shutting the throttle smoothly rather than grabbing big handfuls. On a track, try doing a few laps in one gear without using the brakes, using only the throttle to control the bike.
The best place to practise is off road, where you can feel every throttle input. A trials bike is great: it goes very slowly with very short gears and you can do anything you want with the throttle. You can practise finding grip, moving your body weight and using the throttle to see what it does on a slippery surface. Practice spinning the wheel when it's upright, then lean it over, carry a partial throttle and open it suddenly to get it sliding. It's difficult to acquire these skills on the road, but you can do it easily on the dirt.