engine breather

Hello all, hope everyones alright. I been on hiatus because my job during summer i cant really do anything working up to 16 hours a day. But im back at it i bit the bullet and purchased vm34s . Not bad easy to put them on and take off and look good. I still have an issue with a sucking noise on...

Upon replacing the old petrified breather vent hose, I came across short sections of rubber tubing inserted in each vent. On this bike, I am sticking with the factory airboxes, so the hoses will run into the boxes. Do I need to keep these rubber pieces installed in the vents? As far as...