Triple K&N RU-2780's will fit under the claw, but it's tight, which are the one's Warp is referring to.
Some have added spacers to the mount points to make the claw stand out for an easier fit.
Turbo the only filters that fit under the claw with out doing mods that I know of is the little filters everyone is using which give more power the the under the tank or seat style yet still rob a lot of flow verses the RU-4040-1 pictured above.
Triple K&N RU-2780's will fit under the claw, but it's tight, which are the one's Warp is referring to.
Some have added spacers to the mount points to make the claw stand out for an easier fit.
The spacers if you choose to use them are not very large so the bear claw movment is not very noticable. Some just rotate the rear filter and get the claw on that way. Its give and take when you want more power.
For a spacer, just undo the mounting bracket at the back of the claw & refit with a nut behind the bracket! easy peasy! Doesn't look any diff, but gains a few mm space