Didn't really start out with this mod in mind, however when fitting some heated grips I came across an issue which meant I would need to change or modify the throttle tube. Definitely think its worth the £20 and 20 minutes of your time, takes out the initial slack and makes the whole throttle action more positive.
I just got the details from this thread https://www.ducatiforum.co.uk/threads/r1-throttle-mod-on-999.921/page-1 Watched a quick youtube vid, (bikes different but the process is the same) Ordered the part from my local Yamaha dealer, was here within a week.
It's a really quick and easy mod. Just take the oem one off, noting how it fits and works and replace it with the Yamaha one.
Part number in this thread: https://www.ducatiforum.co.uk/threads/r1-throttle-mod-on-999.921/ If you are anal like me you will need to by the left grip to match too.
I bought a pair of pro grips. They are in two layers with red showing subtly through black. Perfect for a red bike and probably still v smart on a black one
Also, they are shorter than the standard grip so either get the hacksaw out or wrap the end in black electrical tape. Other colours available (apparently).