These bolts mount the air cleaner backing plate to the heads.
1986-1990 air cleaner bolts have 5/16“x18 threads (cap head screws). ¹⁾

1991-2003 air cleaner / breather bolts. Thread pattern is 1/2”x13 with a 5/16“ through hole for the engine to breath from.
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2004-up air cleaner / breather bolts. Thread pattern is 1/2”x13.
There are 2 different size holes thru the middle - nominally 1/16“ (1.5875 mm) in the rear and 5/16” in the front). ⁴⁾

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Here is the OEM ham can without the filter.
The two bolts on either side of it are the breather bolts that go into the heads.
(and where the oil mist comes out).
With the stock configuration, the mist is vented back into the intake.

Backing plate (29367-07A)8)

SCREAMIN’ EAGLE® PRO HIGH-FLOW AIR CLEANER KIT FOR SPORTSTER® MODELS. ⁹⁾
(For race application only)
This air cleaner kit provides increased air flow when used with stock, or Screamin’ Eagle carburetors.
It includes a composite backplate, an air cleaner cover adapter, and a high flow, washable element that does not require oiling (K&N).
The breather system also has been redesigned to route breather gases directly into the inlet of the carb to minimize excess oil in the A/C assembly.

29042-04A:
Fits 2004-later XL models with stock air cleaner cover.
If using HD Swingback air cleaner cover 29742-04 a separate purchase of adapter kit P/N 29848-04 is required. $109.95 29066-03:
Fits 1988-2003 XL models. $109.95

For instruction sheets, Click Here to go to the Instructions page in the Sportsterpedia.
Click on the “Y” next to sheet# J03274 for the air cleaner kit and and sheet# J03214 for the adapter kit to download and them.

SE Air Cleaner (29066-03) 10)

29042-04B:
SCREAMIN' EAGLE® HIGH FLOW AIR CLEANER KIT Fits 2004-later XL Sportster® model motorcycles with Stock air cleaner cover.
If using HD Swingback air cleaner cover 29742-04 a separate purchase of adapter kit P/N 29848-04 is required. NOTE: EFI models must recalibrate the ECM when installing this kit. Failure to properly recalibrate the ECM can result in severe engine damage.

For instruction sheets, Click Here to go to the Instructions page in the Sportsterpedia.
Click on the “Y” next to sheet# J03663 for the air cleaner kit and and sheet# J03214 for the adapter kit to download and them.

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