Most road going motorcycles have a throttle that needs to be turned about a quarter turn or slightly more to be fully open. It's a compromise so less experience riders can tame fast motorcycles. Some people, like you, want a faster response and fit a quick action throttle. We've seen universal ones but we reckon those designed to work on a specific make or model of motorcycle are best. Loads of tuners sell them or you could try one of the online motorcycle parts sellers. For example Cycle Pirates Quick Motorcycle Throttle Kit
Is there some sort of device I can get that enables me to have the throttle fully open without having to twist the throttle all that way round, because when you watch WSB and MotoGP they have the throttle fully open with only a slight twist.