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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
I've decided to return to the old school or at least "original school" air cleaner assembly on my 2002 Fat Boy with CV carb. Call it nostalgia I guess now that I've owned it over 20 years.
Using all the OE stuff including the backing plate is there a better way to vent the crank case then into the air filter like stock?
I've decided to return to the old school or at least "original school" air cleaner assembly on my 2002 Fat Boy with CV carb. Call it nostalgia I guess now that I've owned it over 20 years. Using all the OE stuff including the backing plate is there a better way to vent the crank case then into the air filter like stock?
Yes. Lots of ways to do it. DIY ways or kits like available from Trask.
Yes. Lots of ways to do it. DIY ways or kits like available from Trask.
Trask's website doesn't show much of anything for my application. Mostly for their breather or other aftermarket. The search for a Screamin Eagle backer turns up a million things but nothing specific for me yet. I'll continue on with the search.
I guess I have to expect nothing to pop up immediately for an old bike.
Trask's website doesn't show much of anything for my application. Mostly for their breather or other aftermarket. The search for a Screamin Eagle backer turns up a million things but nothing specific for me yet. I'll continue on with the search. I guess I have to expect nothing to pop up immediately for an old bike.
I vented head breathers to the atmosphere on my carbureted, all bore 107 in my '02 FLHT; old bike. I can tell you how I did it but don't know if it fits your application. I used the SE backing plate; early version, Zippers "Mo Flow" air filter and the OEM footbal cover modified to allow more air to the filter. The SE backing plate has two holes where the OEM head breather hoses entered; venting into the intake. I tapped those holes for 1/4" NPT brass pipe plugs; don't trust epoxy or silicone to fill those holes.
I ran a CV44 on this motor and the parts used to vent are shown in the attached cut out from the '09 SE Performance catalog. The backing plate attaches to the bracket and the bracket attaches to the head breather bosses via the two breather bolts with the two hose fittings between the bracket and the head breather bolts. Hoses are attached to those two fittings and routed to a "T" fitting and the single hose from the T fitting routed to wherever you want the crankcase mist to vent. Some vent open to the atmosphher, some vent to a catch can or a small filter of sorts. Maybe you can visualize from the attached cut-out from the '09 SE Performance catalog.
If your backing plate is the later configuration that does not have the hose fittings mounted between the backing plate bracket and the head breather bosses, you will have to drill and tap the "nipples" from the backing plate that attach to the head breaher bolts to install some 5/16" brass hose fittings.
Sorry if this is hard to follow but the best I can do to illustrate what I did that worked very well. Don't know what backing plate you have so flying blind.
I have attached a few photos that might help.
I vented head breathers to the atmosphere on my carbureted, all bore 107 in my '02 FLHT; old bike. I can tell you how I did it but don't know if it fits your application. I used the SE backing plate; early version, Zippers "Mo Flow" air filter and the OEM footbal cover modified to allow more air to the filter. The SE backing plate has two holes where the OEM head breather hoses entered; venting into the intake. I tapped those holes for 1/4" NPT brass pipe plugs; don't trust epoxy or silicone to fill those holes.
I ran a CV44 on this motor and the parts used to vent are shown in the attached cut out from the '09 SE Performance catalog. The backing plate attaches to the bracket and the bracket attaches to the head breather bosses via the two breather bolts with the two hose fittings between the bracket and the head breather bolts. Hoses are attached to those two fittings and routed to a "T" fitting and the single hose from the T fitting routed to wherever you want the crankcase mist to vent. Some vent open to the atmosphher, some vent to a catch can or a small filter of sorts. Maybe you can visualize from the attached cut-out from the '09 SE Performance catalog.
If your backing plate is the later configuration that does not have the hose fittings mounted between the backing plate bracket and the head breather bosses, you will have to drill and tap the "nipples" from the backing plate that attach to the head breaher bolts to install some 5/16" brass hose fittings.
Sorry if this is hard to follow but the best I can do to illustrate what I did that worked very well. Don't know what backing plate you have so flying blind.
I have attached a few photos that might help.
Thanks for the leads. I'm returning to the stock football or ham can 2002 air cleaner, so the backer plates is from that.
I'm wondering if a Kuryakyn 9920 spacer like the one pictured would work? Instructions say to reuse the stock breather bolts and hoses. On the second photo, which is from the Kuryakyn instructions one hose is shown hanging down after installation. Maybe could throw a filter on that and keep it all hidden behind the backer plate? Or go with a catch can?
But the installed photo still looks like they dump out of the spacer and in front of the carb opening, thus allowing mist to be sucked in. Or am I misunderstanding here? Even some type of spacer that would allow banjo bolts behind the stock backer would probably work if I could find such an animal. I've read that the Kuryakyn spacer will set it out about 5/8".
I've been doing some more searching. Looks like some kits come with a bracket that would set the backer plate outward a little to allow banjo bolts that also come with a kit to be used in venting. Like a Kuryakyn 9930 but that kit appears to be for Mikuni and I have a CV. But then again that bracket would create a gap between the backer and the carb.
Understand but my point was that you can retain the foot ball cover without the matching back plate like I did. Enclosing the filter limits air flow which makes it challenging to use a high flow air filter.
Understand but my point was that you can retain the foot ball cover without the matching back plate like I did. Enclosing the filter limits air flow which makes it challenging to use a high flow air filter.
not to mention if you put the filter or catch can inside the filter cover then you'll have to remove that each time you need to empty the catch can or filter. Im lazy and hate adding steps to anything I do thats supposed to make something better lol. I run my football cover with a high flow filter under it without the backer plate. Did you look at dkcustoms.com yet? If nothing else you might see something thatll give you some ideas
Understand but my point was that you can retain the foot ball cover without the matching back plate like I did. Enclosing the filter limits air flow which makes it challenging to use a high flow air filter.
I've got some hardware on hand like a complete Roland Sands Designs turbine type air cleaner and another old large cone shaped K&N filter with hardware setup. Maybe I can do something similar to what you did and go with a different backer and retain the football cover with some parts mixing & matching. Thanks for the suggestion.
Originally Posted by Screamin beagle
not to mention if you put the filter or catch can inside the filter cover then you'll have to remove that each time you need to empty the catch can or filter. Im lazy and hate adding steps to anything I do thats supposed to make something better lol. I run my football cover with a high flow filter under it without the backer plate. Did you look at dkcustoms.com yet? If nothing else you might see something thatll give you some ideas
I was thinking that the thing wouldn't have to be emptied too often so inside wouldn't be a big deal. We're talking a 20 year old bike with about 46k miles on it so there isn't a big yearly average.
But if I can run that cover without the OEM back that should free up some room for other crankcase breather options, correct?
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2002 crank case vent
