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Question about rerouting breather line to air

5153 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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Ok, that's a good explanation. What do you think of the S&S reed breather
This engine has 5k on new James gaskets umbrella valves. When I was fixing a couple broken bolts in cone cover, I threw I the reed breather. The nylon timing breather looked ok, I was just updating stuff preventative. Bottom end had 120k miles. All next top end was done.
Reed seems to blow more oil, but I do tend to ride it harder now
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