Can M8 heads be set up for external breathers with a barb directly in the head, like a twin cam head can?
Sure. I gave it a shot just seeing if it would work one day with a customers bike.
i don't know of anyone who makes a Kit for it. i did an experiment with one using the 1/2 Tube and old style Breather Bolts which fit and worked fine. The part I couldn't find was anything to off-set the filter back plate. I had plenty of bolts but none of the spacers. Experiment stopped.
Someday I'll get board and go through the old parts bin looking for something. Still have to come up with something to close the space between the intake and filter back plate.
I suppose one could drill the current back plate, use Silicone Hose and a "T" behind the Back Plate and run it to ground for a filter like the old ones.
What I meant was an actual breather machined in to the head itself. So a barb attached to the head and vent lines run off from there. Not going in to the air filter backing plate at all.
I don't see a convenient space to drill/tap on the M8 heads, like is available on the TC heads.
OK thanks, that what I was looking for.
How about in the rocker cover?