Rok's Custom Exhaust

It started a few months ago; patiently I waited for a set of RH dooleys with smooth shields and fishtails. A couple weeks ago I get word from Meancycles that RH will -finally- be drop shipping my long-awaited exhaust system. Life is good again. For a week.

The system never gets here. I can't contact RH and Meancycles can't either.

Last week I vascilate between trusting an Ebay vendor who'll deliver what I want in the RHD system, minus the fishtail ends. I consider buying a V&H Nomad system, actually spent about a minute considering a Cobra true dual system, even considered a stock 'Nad system.

The idea that appealed the most to me was building my own Bagger system using stock headpipes, having some stainless pipe bent, then installing a pair of Rinehart slip-ons (which I still may do).

But then I got to really thinking practically; what did I want from the exhaust? Performance? Looks? Uniqueness?

Then ideas began coming in waves. I called my fav automotive exhaust shop and got Jess the owner. I asked if he had any stainless 1.5" pipe around. He answered he did not but would order a stick and it would be there Friday. I drug the complete Classic exhaust system out of the shed, pulled the upswept cobra off and began fitting pipe. I put the two OEM headpipes on and that's when it occurred to me "WHY do I want a bagger system? OK it looks cool but this is a SOLO Cruiser, not a tourer; it'll likely never have saddlebags on it, much less hardbags.

Regarding LOOKS, the bike ALREADY has "the look"! In fact, it has a full rear bumper system and bumperettes which for the most part are hidden behind PIPE. It doesn't NEED an exhaust system to enhance the look. What's the best performance system to be had? I remembered an article written for HD that spoke of scavenging, radiused 2 into 1 that did all that.

I went out and began figuring angles and compiling a mental materials list. I would build a 2:1 header with an oval collector and dump the whole works into a RECTANGULAR muffler. If I did my work right, I could maintain BETTER than the 1.25" ID of the stock headpipe all the way out the exhaust outlet. I sketched a drawing and began gathering materals, quickly finding out just how difficult getting all the pieces in stainless was going to be! I already had the 25% and 50% perforated 18 ga I needed for the baffles. If it was going to have to be cold or hot-rolled steel, sobeit. I set off in search of the steel. I found some stainless flatbar in a couple widths and thicknesses at a yard in Longview, the rest I got from an even larger yard in Portland.

Brainstorming now in full swing, I began to mentally piece it together, looking for support points on the bike to hang the system and refining my drawing where I could.

The system will be two sub-assemblies: The headpipes and collector with a welded two-hole gasketed flange which would join the muffler to the header. Both would be hung in the rubber mounts from the ex-catalytic convertor.

I measured everything three and four times, sketching how I needed Jeff to bend the staineless pipe that would join the factory headpipe to the muffler.

I got to the muffler shop at noon Friday only to find out that it would be Monday before he got it. I had my sketch with me PLUS had taken a number of pictures and put them on my laptop, which I also had with me and showed him. He suggested that what I should do would be to have him bend me up my two pieces in cold-rolled 1.5" pipe and see how it was going to work. If all went well he'd duplicate those peices for me in stainless on Monday. Hell of an idea! He did that and charged me $10.00.

Before I left I asked him "Say I get this header built and see it's going to work. Could you fab the entire header out of stainless for me?" "Maybe!" he says:-)

I spent the day building the header. I woulda been done quite a while ago except working with the OEM pipe is a B!@#H! It's doublewall pipe; 1.5" stainless outside with a 1.25"ID 1/16" thick cold rolled inside. Ever try swaging doublewall pipe using a Harbor Freight 1.5" pipe expander? 5 minutes after getting home with it, I was headed to the hardware store for a grade 8 7/16" fine nut and bolt. Minutes after arriving home with the new bullet-proof hardware, I was removing what was left of the expander pieces from the inside of the pipe. It's scrap now. I couldn't expand it so would HAVE to find a way to cut 3/4" of the cold rolled pipe and remove it from inside the stainless piece to fit the new pipe into it. A new dremel tool and 10 micro-sized diamond (HA!) cutting wheels and the deed was done.

I fit the new peices in place and sliced the ends to form the collector. I started with my MIG welder but couldn't get the feed right on the lowest heat setting and had to resort to Oxy-Actylene and a wire coat hanger to join the two header pipe. It looked like CRAP! Definitely NOT some of my better work but I cleaned it up and did a test fit. PERFECT!

I cut the flange from 2X1/4" flatstock, drilled the 3/8" mounting holes and cut the 1.5" hole in the center. Tomorrow I'll enlarge the hole with a carbide bur, then will begin building the muffler from the 2X6X1/8" rectangular. The overall length of just the muffler will be 10". In that 10" the passage will do two 180 turns, have perf face along the passages and will be packable using course stainelss steel wool from the leaving end, via a bolted 2X6 50% open perforated insert. Despite the 180s, the diameter of the passages will actually increase in size from the collector. Looking at the left side of the bike, all that will be visible of the exhaust will be a 2x6 rectangular pipe, about 1.25" in front of the tire and about that same distance below the driveshaft housing at a slight back and downswept angle. It will stick out about an inch less than the left sidecase cover. I have some 2"X1/8" stainless flatstock that will cover the top and sides and be tack-welded to the outlet and likely be polished.

I made the high temp gasket for the header to muffler, wrapped the pipes with header wrap and installed stainless slats in the muffler outlet.
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