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DIY Tech: H-D Heavy Breather filter and cover kits

Tech & How-to

DIY Tech: H-D Heavy Breather filter and cover kits


You might remember our Milwaukee-Eight bagger from the last issue where we installed a set of slip on-mufflers from TAB. The mufflers woke up the cruising performance of this bike and added a bit of bark to the exhaust note. In this issue, we add a Harley-Davidson Heavy Breather air filter and dress it up with a decorative cover from Harley-Davidson Genuine Parts & Accessories. We chose the black finish breather and cover because this is a Street Glide Special, and most of the bike is trimmed in black. But the Heavy Breather filter kit is available in chrome, should you decide you want a bit more bling.

The iconic Heavy Breather Air Cleaner features an angular cone-shaped oiled cotton filter element that flows a large volume of clean air into the engine. The short, low-profile cast air tube rams the charge directly into the throttle body with little turbulence for increased power and torque. That intake tube mounts to a custom backplate that features integral breathers and also covers the throttle body and electronics for a finished look.

The Heavy Breather is shaped to allow installation on Touring bikes equipped with fairing lowers, however, you may need to remove the intake tube from the back plate for servicing and cleaning the filter element. If you have no fairing lowers, like on our bike, the filter will slip right off after loosening one band clamp.

The kit includes a washable and rechargeable filter, intake tube, custom backplate, water-repellent rain sock and all mounting hardware. This part is 50-state EPA compliant and has a one-year warranty. Harley suggests an ECM recalibration, but our fuel figures were not too bad once we did a couple dyno runs. Remember, we still have the stock headpipe on this bike.

We also bolted on a two-piece billet decorative cover with this Milwaukee-Eight Heavy Breather. It’s also gloss black with a machined Screamin’ Eagle logo. It’s manufactured from forged aluminum and precision machined to tightly wrap the filter element. The cool cover exposes a majority of the filter to maximize airflow, and the rain sock that’s included with the Heavy Breather kit still fits!

The bike’s owner, Mike, says, “It runs great, no popping, pulls hard, no lagging. Dyno John said the factory head pipes and cat keep the engine from really flowing. It’s fine. It’s an old man’s bike.” While we’re sure there’s a certain element of youthful riders aboard Harley Touring bikes, we just can’t resist ribbing Mike. Besides, he said it, not us. Perhaps this Heavy Breather air filter is helping Mike feel young again. I guess Harley-Davidson has discovered the fountain of youth. And it’s available at your local Harley dealer parts counter.

Here’s the two kits: the Heavy Breather filter kit and the filter cover. All parts are heavy duty, made of metal, and a perfect fit.

1. The stock air cleaner might be low profile, but the styling is cookie-cutter and the element is not washable.

2. Remove the stock air cleaner cover, filter element, and backplate.

3. The metal induction module support bracket is also removed with a 5mm Allen wrench. The throttle body control wires are zip-tied to this bracket. Cut the zip-tie (arrow).

4. Install the new zip-tie, with special sliding fastener to the back of the threaded boss on the throttle body (arrow).

5. Then secure the throttle body wire harness with the zip-tie. Cut the excess zip-tie with sidecutter snips.

6. Attach the throttle body cover to the back of the air cleaner backplate with three self-tapping screws using a Torx T20 driver.

7. Align the holes and stick the backplate gasket to the air cleaner backplate.

8. Stick the two small square ring gaskets into the counterbores on the back side of the air cleaner backplate.

9. Insert the three backplate mounting screws (with thread lock compound) into the air cleaner backplate and start the threads. Do not tighten at this time.

10. Place the large O-rings into the breather bolthole bosses.

11. Install the two breather bolts and tighten with a T45 Torx bit. Alternately tighten the two bolts and torque to 120-144 in-lbs.

12. Tighten the three backplate screws started in step 8 with a 5/32″ Allen wrench and torque to 55-60 in-lbs.

13. We opted to install the optional Screamin’ Eagle air cleaner cover. So at this point, we’ll assemble the cover to the intake tube and filter. Start by sticking the round foam insulator to the inside of the air cleaner cover.

14. The mounting ring is not symmetrical. There is a wide portion and a narrow portion. It will only fit properly one way.

15. Place the cover over the filter and the mounting ring and band clamp cover (included in Heavy Breather air cleaner kit) over the base of the filter. Attach the mounting ring to the cover with four Allen head screws using a 9/64″ Allen wrench. Tighten the screws to
15 in-lbs.

16. Install the assembled air filter element and cover onto the intake tube and tighten the band clamp with a screwdriver or 5/16″ nutdriver. Align the filter now by placing the tube flange on a flat surface, or do the final alignment on the bike and tighten the band clamp.

17. Align the mounting gasket. There is a half moon cutout that will match up with the same shape on the back of the mounting flange.

18. Install the assembled intake tube to the backplate with three Allen bolts. Tighten the bolts with a 3/16″ Allen wrench and torque to 55-60 in-lbs.

19. The Heavy Breather also comes with a rain sock. Find a place to store it on the bike until needed.

20. The finished product looks, and works, better than the stock air cleaner. Plus, the Heavy Breather uses a K&N brand filter, which can be cleaned and reoiled time after time. AIM

Tools Needed
• T20 Torx driver
• T45 Torx bit
• 5mm Allen wrench
• 5/32″ Allen wrench
• 9/64″ Allen wrench
• 3/16″ Allen wrench
• Sidecutter snips
• Flat-bladed- screwdriver
Or 5/16″ nutdriver

Tips & Tricks
If you are not
installing the accessory filter cover, the filter element can be attached to the air tube now.

Genuine Parts &Accessories Heavy Breather air cleaner, black
#29400264, $399.95

Heavy Breather air cleaner cover, black
#61300688, $199.95

Dyno Solutions


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