BCM Pinner Air Cleaner Installation | Stupidly Simple Engine Breathing

Building the Lil Devil, Part Two

1305 Engine Breathing Lil Devil

Air Cleaner Installation Pinner Air Cleaner
1305 Engine Breathing Carburetor
Cnc Machined Vortex Cone
1305 Engine Breathing Thread Locker
1305 Engine Breathing Uni Filter
1305 Engine Breathing Flat Head
1305 Engine Breathing Willis Bolts
1305 Engine Breathing Tightening Bolts

In this over-complicated world of taking three steps to go back to the first while stepping over dollars to pick up pennies, we have seen many over-engineered motorcycle products. Sure, may products offer advantages to their amount of parts, but as of late we have been seeing many custom bike builders going the simplified “less is more” route. One of these talented builders and parts manufacturers is Kim Boyle of Boyle Custom Moto (BCM). He has an eye for what should be stripped off a bike and shit-canned, yet keeping the necessary parts intact and adding just what is needed to make them perform better. In part two of getting our 1999 Lil Devil Sportster together for Mexico’s El Diablo Run, we are working on getting our newly upgraded motor some more breathing with less clutter and have employed a few of BCM’s products to do so. First for better intake breathing we installed a made-in-the-USA BCM Pinner Air Cleaner ($205). At 4 inches around and 1-1/4 inches in depth, this small air cleaner can suck it with the best of them. This is due to BCM’s Vortex Cone CNC-machined into its mounting base. BCM also worked with filter element company UNI to get just the right foam filter density for a Harley’s air intake needs.

Since the Pinner is such a small air cleaner, Kim thought it best to leave out constructing a crankcase vent system connected to the filter and went with a simplistic genius idea of making two small units that vent to the atmosphere instead of recirculating the gasses back into the carb. These vents, dubbed Willis Bolts, are comprised of two hollow stainless steel fasteners that screw directly into the vent holes on the heads. To keep things breathing and not spewing, the fasteners each have small Uni filters and screens that are held in with C-clips. Each of these products takes minutes to install, work great, and are simplistically stark in contrast to the competition. Charles and Ray Eames would be very proud.

1. Here is a shot of both the Willis Bolts and the Pinner Air Cleaner.

2. This will be its new home; a newly upgraded S&S; 1200 Kit and the ever so sweet S&S; Super E carburetor.

3. This shot shows the CNC-machined Vortex Cone that aids in driving a better amount of air into the engine than stock.

4. After coating the three bolts with blue thread locker, we installed the Pinner’s base plate.

5. We then installed the Uni filter element, stainless protective mesh, and the faceplate of the air cleaner over the Vortex Cone.

6. With a single flat-bladed screwdriver, we bolted the Pinner air cleaner together. Talk about a simple installation!

7. Moving on to the Willis Bolts breathers, as you can see each of these has almost just as many parts as the air cleaner.

8. After coating each of the stainless steel fasteners with a few drops of blue thread locker, we securely tightened them into the heads of the engine.

9. The mini Uni air filter foam was installed into each of the breather bolts with care not to push them too far into the bolt.

10. The stainless steel mesh screen was then installed into the Willis Bolts. This keeps the foam where it needs to be and also protects it from the outside world.

11. A C-clip was then carefully installed inside the breather bolt’s inner recess. This holds both the filter element and the screen securely in place. We were then done.

12. As you can see, both the BCM Pinner air cleaner and the Willis bolts did a great job of sucking and breathing without any unnecessary clutter.