Took the air filter off and there was a good coating of oil from the breathers on the inside. Decided to fit an external breather but I'm left with 2 holes in the backplate.



I have plugged the holes with bolts and short bits old breather tube.



Question is, do the backplates always come with these 2 holes or were they made to fit the 2 breather pipes? Is the backplate available without these holes?

Thanks

 

I think the answer is yes, you can get them without the two holes, but I also think it totally depends on the bike/year.

https://mstore.harley-davidson.com/s...rmance-filters

 

Most of the air cleaners will recycle the blow-by back into the intake via holes in the back plate. DK Customs makes some breather assemblies that vent to atmosphere with no holes. Venting to atmosphere is a ton better for the engine and I customized my Ness Big Sucker to vent to atmosphere. I tapped the vent holes and ran two 1" set screws in them with a ton of red loctite and peened the edges so they can never back out. Then I drilled and tapped the bosses and plumbed my vent lines to a filter.

 

I plugged mine with bolts after I removed the nipple. It screwed out the back easy. I then went to Auto Zone and bought a small universal air filter and just let it hang down between the cylinders. Functions just like the picture above, biggest difference is in the looks. With the filter and rubber tube, I have $13 invested to convert mine.

 

Interesting post and replies, I don't remember seeing a backing plate with those holes tho. DK's kit only $45, that's interesting as well.

 

So here was my final result...

I'll live with the old holes in the backplate being plugged with bolts until I can find a replacement on FleaBay or the like. I decided to go upwards with the pipes so hopefully, the oil will mostly return to the beathers & not leave via the filter. For now, I just used a longer bolt on the top engine mount & fixed there.







It's now peeing with rain & so I'll test ride later... will let you know the results!