Thought I would compile some info about the differences in the various R6/R1 throttle tubes here, consolidated from some of my posts on ADV. It may help people that are confused about the conflicting info on this subject.
1999-2005 R6 - 1/5th turn
2006-2009 R6S - 1/5th turn
2006-2009 R6 - 1/6th turn
And the R1 throttle tube is also 1/5 turn.
If you have the black R6 throttle tube, the part number is 5SL-26240-01 and its the smaller cam 1/5 turn tube from the older R6, the R6S, or the R1. If you have the white R6 throttle tube, the part number is 2C0-26240-00-00 this is the larger cam 1/6 turn from the newer R6.
Sometimes with a getoff or bad landing the idle stop can roll under the housing past fully closed throttle and start sticking. This has happened to me, its because the stops on the DR650 tube are taller than the yamaha tube. And even though the DR650 cam looks bigger, the part where the cable rides is actually smaller since there is a groove on the sides that the cable rides down in, where on the R6S throttle tube the cable rides right on top of the cam. There is no groove on the sides.. This is the R6S (5SL-26240-01) throttle tube. The regular R6 (2C0-26240-00-00) has an even larger cam, which may be closer to the outside size of the DR650 cam, so it might not have the problem of rolling past the idle stop. For some reason I haven't thought of adjusting the cables. I just file down the idle stop on the R6S throttle tube to match the size of the idle stop on the DR650 throttle tube. On the latest R6 tube it took about 30 seconds with a grinding stone on the dremel. Really easy. But this probably explains why some people don't modify the R6S tube, they just adjust their cables instead
I decided to hold off ordering the more expensive R6 tube, and will just run this R6S (5SL-26240-01) tube until I wreck it, which will happen eventually. Like I said above, since the R6 (2C0-26240-00-00) tube has an even larger cam then the R6S tube, I think it might fix the problem of rolling past the idle stop and then sticking after that happens. Plus it will be an even quicker pull. I just don't know if it will fit in the DR650 throttle tube housing, I know the SV650 guys have to grind down their housing a little to make it fit. Eventually I will order one and find out.
Then there are aftermarket throttle tubes like the motion pro ones, that say they are applicable to pretty much all of the R6 and R1 bikes, I have no idea about the size of the cams on those.
Here are a couple pictures courtesy of ER70s-2
on ADV. You can see the difference between the R6S throttle tube on the left and the DR650 tube on the right. Notice how the stops on the DR650 tube are taller, where as the R6S has shorter stops which in certain instances mentioned above can cause it to roll past closed and start sticking. However the cam that the throttle cable rides on is actually a larger diameter than the DR650 which results in the quicker throttle pull. The white R6 throttle tube may have taller stops, not sure yet.
You can also see the left side of the idle stop, this is where I file it down to be the same length as the DR650 idle stop, otherwise when you start the bike you will be at like 4,000 RPMS which is frightening! I guess people have suggested also adjusting your throttle cables to compensate, but I just take 30 seconds and dremel the idle stop to match the DR650s.