One of the first things I noticed when I got my 899 was how bad the throttle felt. There was a lot of slop in it before it did anything, and it just felt loose. I like my bikes to feel pretty highly strung and responsive, and this throttle just really let the bike down a bit for me. The most annoying problem was blipping the throttle on down shifts, I found it difficult to find the sweet, predictable blip that would give me exactly what I was after. I could not reduce the amount of free play in the throttle as these bikes are drive by wire, and it lacked the adjusters that traditional cable throttles have which would have allowed me to fix the problem.
Now, it's worth pointing out that for all practical purposes, the only reason bikes ever had freeplay in their throttles was to prevent the tension in the cables from accidently manipulating the throttle bodies when turning the bars from right to left. With the implementation of drive by wire in bikes, this is now a non-issue, and the only reason drive by wire bikes have it now is to make riders used to the old system comfortable when swapping to new technology.
Which is unfortunate for people like me, who used to just adjust the cables to the bare minimum of freeplay before turning the bars caused problems.
So, being new to these bikes, I did a google search and came up with very little, except for unhelpful suggestions by trolls suggesting that if people did not like how Ducati released their bike from the factory, rather than adjusting them to suit themselves they should just sell them. Yeah, great.
Maybe there are guides out there on how to modify the throttle but if so I could not find them, so I have written this in the hope it may help other 899 owners who hate the slop too.
So. This is one way, a very cost effective way, to fix the free play. It's not the only way, and it might upset the purists who think the only way to fix issues is to pay huge bucks for very little. Meh.
You will need;
12mm hex key socket to remove the bar end
Set of screwdrivers
Set of security bits
Acetone, or other similar solvent to remove grease
Cyanoacrylate based glue, such as Loctite 401 or similar
Good quality PVC plastic of a suitable thickness to give you the freeplay you desire
Various hand tools such as files, Stanley knives, plyers ect
Lithium spray grease to relube throttle
Start by removing the RHS bar end, and then undo the 2 Philips head screws on the plastic throttle housing. It should look like this
Then, remove the 2 security screws on the throttle housing, pull the metal shield from the ziptie on the bottom of the housing and remove the shield. Slide the lower part of the housing down the cable and you should see the reason why there is slop in the throttle.
Slop taken up
Throttle fully closed
If you missed it, the reason the throttles have slop in them is because of the gap Ducati have factored into the throttle grip, in the form of a couple of mm gap in the dovetail of the throttle tube. Seen here
there is another similar one on the rear of the throttle tube (not pictured).
This is what the throttle tube looks like when it is removed, with the grease cleaned off.
So. In order to remove the slop, you need to reduce the clearance of the dovetail with the protrusions on the throttle housing that control the signal going to the engine.
You can do this by cleaning the grease off with the acetone, finding a piece of PVC plastic that will take up this clearance (or as much of the clearance as you want to remove), roughing up the surface of one side of the dovetail and gluing a closely cut bit of this plastic shim onto it.
Once it is dry, you can then cut and file it into a neat fit that will not interfere with the operation of the throttle, relubing the tube and refitting it. With the shims in place, the tube should look something like this
The red circles show the shim in place.
And there you have it. With the PVC shim glued into place in my throttle, I have 0.1mm of freeplay in my throttle now. It absolutely does not pull on the throttle at all, and the shim is going no where. The bike is so much better to ride now, and I just enjoy it that much more. If I ever want to delete the mod, It's as simple a finding a solvent that will dissolve the Loctite 401 or buying a new throttle tube - that's it.
I hope this helps some owners, or inspires you to find another solution. Haters, feel free to flame on