crank case vent
crank case vent
pros & cons
okay so I did the DIY mod and rerouted the cc vent
#4 areoquip hoses to a tee then to 1/4 DOT plastic tubing to the rear of the bike, no filter,, just to the air ,, what are the advantages to this?? other than no hot air into the EFI system, and the mist of oil ,, don't see or feel any difference, why would Harley vent it back into the FUEL BODY anyway,
thanks mike
okay so I did the DIY mod and rerouted the cc vent
#4 areoquip hoses to a tee then to 1/4 DOT plastic tubing to the rear of the bike, no filter,, just to the air ,, what are the advantages to this?? other than no hot air into the EFI system, and the mist of oil ,, don't see or feel any difference, why would Harley vent it back into the FUEL BODY anyway,
thanks mike
Road Warrior
Joined: Jul 2013
Posts: 1,624
Likes: 13
From: Fort Worth
pros & cons
okay so I did the DIY mod and rerouted the cc vent
#4 areoquip hoses to a tee then to 1/4 DOT plastic tubing to the rear of the bike, no filter,, just to the air ,, what are the advantages to this?? other than no hot air into the EFI system, and the mist of oil ,, don't see or feel any difference, why would Harley vent it back into the FUEL BODY anyway,
thanks mike
okay so I did the DIY mod and rerouted the cc vent
#4 areoquip hoses to a tee then to 1/4 DOT plastic tubing to the rear of the bike, no filter,, just to the air ,, what are the advantages to this?? other than no hot air into the EFI system, and the mist of oil ,, don't see or feel any difference, why would Harley vent it back into the FUEL BODY anyway,
thanks mike
The reason HD and every other manufacturer vents to the intake is because of EPA requirements.
Outstanding HDF Member
Joined: Oct 2009
Posts: 2,488
Likes: 30
From: Maryland near DC
it makes no difference in power (well maybe a teeny bit), it is strickly a epa thing...the advantage of removing it from the intake is that it will keep the intake/valves and pistons cleaner by removing that oil buildup from the breather entering the intake and sticking to and burning the hot parts..over time the oil residue buildup can cause the motor to not breathe as well (build up on the back of the intake valves) and raise the compression (buildup on the pistons and cylinder heads) causing the engine to be more likely to ping.. the engine controller will try and compensate for this by adding more fuel and changing the spark timing (depending on the controller used) which will reduce your fuel mileage a bit...
If you have a tuner with auto tune capability, rerun the auto tune. You probably won't feel a difference in the butt dyno though, but your engine will be working more efficiently.
The reason HD and every other manufacturer vents to the intake is because of EPA requirements.
The reason HD and every other manufacturer vents to the intake is because of EPA requirements.
I have no tuner,, bone stock except se slip ons , and air cleaner
Road Master
Joined: Jun 2006
Posts: 894
Likes: 6
I use a Y instead of a T. I found the Y offered savaging. The T seemed add some resistance. Stock venting is 6" or less into your air cleaner which is pulling a vacuum. Running the venting to the rear like you did, or down to the ground behind the primary like I did, adds resistance to the venting compared to stock.
Yea, if anyone doubts this is a good thing should get a flashlight and look into their throttle body after about 15K miles.
Yea, if anyone doubts this is a good thing should get a flashlight and look into their throttle body after about 15K miles.
Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
Likes: 4,573
From: TOAK western branch
Not really. Take some Seafoam mixed with water and a spray bottle and run the engine up a bit while you squirt it in the throttle body. Should do a good job of cleaning off the pistons and a bit off the exhaust valves.
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Road Master
Joined: Jun 2006
Posts: 894
Likes: 6
There's an old thread where a guy posts pics of carbon fouled pistons and valves. Shocked the crap out of me. I use the aerosol version of Seafoam and spray in my throttle body every spring. Then, I run 10-oz of Seafoam in the tank the first fill-up of the season.
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wont this breakup the carbon and send it threw the rings and possably score the jugs ?? carbon is very hard and agresive stuff,