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Question about rerouting breather line to air

5155 Views 11 Replies 6 Participants Last post by  Brand'd
I have a 98 evo head breather motor. To get rid of drippy air filter, I lengthened the outlet hose and ran under frame to the atmosphere.
I was wondering, since originally the hose vented inside air filtered area to carb, it was adding some air to the air/fuel mixture slightly? If you put your hand over the hose when engine is running, you do feel air pushing (and of course oil mist).
I wonder if it affects maybe the air/fuel mixture at idle or so?
I have noticed a little difference on cool damp morning lately.
It's a mikuni hsr42 out of the box for an evo (stage one style headwork and a ev27 cam)
I'm no official mechanic, I'm interested in others opinions
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The engine will pull in what air it needs through the path of least resistance I would not worry about the insignificant amount coming through the breathers as affecting the a/f it’s the oily mist that is affecting it more, that you don’t want going in there.
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