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According to S&S website: Over time, this retainer can fatigue and break, causing chips to flow through the oil system, back into the tank and can causing significant damage along the way.
And how many here have read or heard about a failure like this?
The aftermarket industry is full of solutions to non problems.
I had this noise for a while that sounded like someone dragging a chain across a piece of metal. Drove me crazy.i finally tracked it down to the check valve. When I removed it, it looked fine. I am guessing the spring was weak and the ball was rattling around a bit. I installed the S&S piece and the noise is gone. Is it better than stamped steel? Dunno, but 20,000 miles later and it still works. Oh, and came with a cool sticker!
Not so fast on the transmission cover vents.......
On the new Harley M8 121" VVT engine, they have done away with the head breather valves altogether, and are are now venting the crankcase 100% through a new transmission case cover.
There is a Harley video (I don't know how to attach an MP4, the video I've seen is not on youtube yet.) that explains why they made the change. They claim it allows for bigger passageways, more efficient separation of the oil/air, better drainage of extracted oil right back to crankcase, and better handles the bigger pulses from the larger displacement engines.
It has a hose going upwards from the trans case to the back of the air filter. This system is supposed to reduce the ingested oil from the head breather CCV systems.
On another forum, Joe Lyons, from PowerHouse Cycle & Dyno (KC, MO) said he has inquired of the MoCo and it can be retrofitted to older M8 engines. He has retrofitted the new cover to older M8 engines, blocking the head breather passages and allowing the new trans cover to handle 100% of the crank case venting...
Retrofitting with the new trans cover, you could route a hose up to the air cleaner, or just route it away from the intake and into the atmosphere, a catch can, or whatever you choose to terminate the breather hose with...
Here is Fueling, discussing new changes to the 121" M8 VVT engine, and the new breather system..
Not so fast on the transmission cover vents.......
On the new Harley M8 121" VVT engine, they have done away with the head breather valves altogether, and are are now venting the crankcase 100% through a new transmission case cover.
There is a Harley video (I don't know how to attach an MP4, the video I've seen is not on youtube yet.) that explains why they made the change. They claim it allows for bigger passageways, more efficient separation of the oil/air, better drainage of extracted oil right back to crankcase, and better handles the bigger pulses from the larger displacement engines.
It has a hose going upwards from the trans case to the back of the air filter. This system is supposed to reduce the ingested oil from the head breather CCV systems.
On another forum, Joe Lyons, from PowerHouse Cycle & Dyno (KC, MO) said he has inquired of the MoCo and it can be retrofitted to older M8 engines. He has retrofitted the new cover to older M8 engines, blocking the head breather passages and allowing the new trans cover to handle 100% of the crank case venting...
Retrofitting with the new trans cover, you could route a hose up to the air cleaner, or just route it away from the intake and into the atmosphere, a catch can, or whatever you choose to terminate the breather hose with...
Here is Fueling, discussing new changes to the 121" M8 VVT engine, and the new breather system..
Just started looking into this, your post is timely. I am already running a Trask cover, so I am debating what I will go with for breathers when I replace my heads this month.
Just started looking into this, your post is timely. I am already running a Trask cover, so I am debating what I will go with for breathers when I replace my heads this month.
You still may want to set up the heads with breathers and just plug the bolts. That way if it doesn't work out, you wont have to tear back into it to add the breather valves....
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Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.
Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.
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Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.
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