is their another breather on our bikes for the engine? i cant believe those small holes to the air cleaner from each cyl head are enough without causing a lot of crank case pressure . i am doing a install of a ness big sucker and the breather holes in the banjo bolts look about 1/16 in ,what gives.:dunno

What's wrong with the size of those holes?

Compare that to the PCV valve passages on your average 350 cu in. V8... we're only talking 50-7? cu in. here soooooooo....

yes but the left over from the other valve cover approx 3/4 dia goes into the air cleaner, if the PCV cant handle it like on full throttle.

all automotive engines have a PCV valve to engine vacume and a crank case vent hose to the air filter assy . what does the sporty have besides the 2 small holes.

In the end the issue is total volume right?

So compare cubes of motor and total volume of crankcase vent sizes on a 350 v8 to that on a 70 cu in v-twin and those two "small" holes.

Do you think the total volume of the PCV and breather set-up is more than 5 times bigger? Might be... been a while since I've had a big Chevy v8 in the garage.

But it just doesn't strike me as that out of wack, that's all...