INSTALLING "A" GRADE EAR VENTS

Tools needed:

helmet_uncut
Start with a "B" Grade helmet which has solid fiberglass ear detail.
helmet_drilled
Drill a small pilot hole in the center of the ear detail on each side of the helmet. Be cautious not to use too large a drill bit as it may chip and crack the fiberglass.
helmet_dremeled
Use a dremel with a 1/4" sanding drum to slowly enlarge the pilot hole, test-fitting the brass ear vent until it fits in the dremeled hole and is centered in the ear detail.
brass_vents
The ear vents are Stimpson part #D2263. They are brass with an outer diameter of 1" and an inner diameter of 3/4". You MAY be able to get "samples" from Stimpson.
vents_painted
Paint ear vents inside and out with aerosol flat black paint.
dremel_vent
Carefully dremel the inner edge of both ear vents to allow epoxy to more solidly adhere to surface..
finished_helmet
Apply a thin layer of 2 part epoxy around the inner edge of ear vent then gently insert into dremeled hole in helmet. Make sure vent is properly aligned and hold in place until epoxy sets.