I took on a free '85 XL600 a few years back with a trashed upper end and various other issues. One of the biggest PITA about this particular bike was the mammoth airbox.....I came up with some quick fitting 3D printed intake manifolds to replace the airbox! They work amazing for me, several others have discovered them as well and I thought a thread for these might be warranted. Bye-bye airbox!! Not to mention obsolete impossible to find rubber intake manifold boots-to-carbs that are cracked and leaking!!!