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 This is a quirky series based on no facts or guidlines besides, “some filtration is better than nothin’.” When we rebuilt the top end of this 61-inch ’48 EL, we added two beautifully finished, hand built/altered Panheads that accept two polished 42 mm Mikuni carburetors. We didn’t know what the hell we were going to do about air cleaners at that point. The heads were originally modified thirty years ago, but recently rebuild, ported and flowed by Baisleys in Oregon. If you want a set of heads carefully dialed in, Baisley is the family team to do the job. I was so impressed with their workmanship I kept the heads at my office to show them off to visitors.
 Originally, when I finally installed the heads we didn’t know what to do regarding air cleaners or even velocity stacks. The problem was my long leg. If I ran velocity stacks and leaned my leg against them, I would shut off the air flow and kill the bike. In addition, since the carbs were on the outside of the engine on the left, they were obtrusive. That aspected of the problem dictated that I not run anything that stuck out any farther.
 If I didn’t run anything at all there were two negative conclusions. One, since the carbs were stuck into rubber spigots, they would fall off if not held into position (many Mikunis are held in place with the air cleaner backing plates which are bolted to the engine). Second, if my leg brushed the openings of the carbs, I would shut off the air again. I had to do something. My first nutty notion was to create a rough dual cage that would prevent my leg from shutting down the carbs. It worked, held the carbs in place, but didn’t contain any element of filtration. I’m not a velocity stack sorta guy. I’d need to be a lot richer to consider sandblasting the inside of any well-running engine. So my cage system bothered me from time to time. I stumbled into a Jap Bike shop recently and discovered foam sock air cleaners for dirt bikes. I bought a couple, modified them, slipped them over the brass belt buckle cages and fastened them with tie-wraps. Done deal, but it wasn’t perfect and hindered the air flow into the mouth of the carbs.
 That’s when we slipped on beer-soaked thinking caps, pondering our options and alternatives. I also spotted those little Pep Boys, single-throat, air cleaners with the paper elements. Chris Kallas pointed out a notion at Larry Settle’s bike shop one afternoon behind a couple of brews mixed with white-lightening. If I developed a flange that aligned with the mouth of the carbs, much like Velocity stacks, the air cleaners could be clamped in place. I took his notion and ran at it like a blind dog digging for a bone. The more I worked, brazed and ground the more trouble I ran into. The concept was cool, but it wouldn’t hold the carbs aligned, plus I still needed some sort of cage to keep the foam aircleaners from collapsing against the mouth of the carbs. I fitted, ground and attempted to braze the pieces together. I noticed at the muffler shop that the tubing said aluminum on the side. I asked one of Tim’s helpers if I could braze to it. He said, “sure.” The tubing was steel, just coated with aluminum. You can weld to it, and you can braze to any areas where the aluminum coating has been ground away. After four hours of off and on brazing and destroying two more foam air cleaners I tossed the whole works in the shit-can.
 I took a ride to Pep Boys and inspected their vast wall of varied sized paper air cleaners. I found something I thought might work. In fact these units would fit right over the mouth of the carbs. Ah, but that wouldn’t hold the carbs in place. I went to my buddy’s San Pedro Muffler shop and laid the notion on him. We had to make two, 1-inch segments of exhaust pipe and expand the opening on one end to fit over the mouth of the carb for alignment and the other end just slightly to fit snuggly inside the air cleaner. This was a trick and took several trips to the muffler shop, until Tim, the owner, threw us out. The small segments created some difficulty while trying to expand one end without damaging the other.
 He finally came close and I took the segments back to the headquarters and began a series of alterations to make all the elements fit. I ground the inside of the segment that was going over the Mikuni mouth. I sanded and ground the aluminum area on the carb to accept the tin exhaust tubing, which would hold the carbs in place perfectly. Finally I saw success ahead as each segment finally fit. Then I cut the strap for the center after I made a diagram and attempted to fit the two segments together on the bench. Once on the carb it didn’t fit, and I had to start the strap process over. This time I put the tubes on the Mikunis, then cut and ground a piece of bar stock to fit. Then all the elements were transfered to the welding bench. I found a flat surface and began to weld. I attempted to gas weld first. I was concerned that I would blow through the thin exhaust tubing with my new MIG welder (I lack experience).
 The gas welding wasn’t progressing as well as I thought it might. The heat was taking its toll on the edge of the tubing and would cause extensive grinding to make it fit again. I stopped and broke out the MIG. I practiced for a while adjusting the voltage and wire feed. I finally got up the guts to attempt the short welds along the strap to the tubing. It worked out fine. I cleaned the welds and polished the inside of the tubing with emery cloth one final time before painting the exterior with a heavy gloss black rustoleum paint.
 Then I discovered one final glitch. The cheapo air cleaners were designed to be fastened with set screws, bogus ones that were basically sheet metal screws. I jammed to the hardware store and bought a couple of Allen 10/32 set screws. I drilled the holes out and taped them to fit the set screw, then buried the screws in blue Loctite.
 Just one final touch. The long 5/16-inch bolt that held the unit in place fit fine, but since it ran between two straps and a bracket to the top motor mount, with a large gap inbetween, it would flex if tightened too much. So I drilled the end of the bolt and installed a cotter key to prevent it from ever backing off.
 I think that’s it. Let me know what you think. –Bandit
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