Boosted Bopper


My name is Andrew James and I’ve always had a passion for turbo charged machines. I work out of a shop in Bradenton, FL called Rodz Welding, where we specialize in aluminum and stainless steel tig welding. I picked up my very first Harley Davidson, a 1991 1200 Sporty on Craigslist back in May. Being the grease monkey that I am, I only rode it for a week before I started chopping and stripping the bike down.

First order of business? Boost! After doing some research, I found out that blow-through set ups are the way to go. To run boost in a carburetor, a boost reference fuel pressure regulator and fuel pump are needed. Then, you run vacuum lines to your float bowl of the carburetor.

I wanted a carburetor that could handle the job, so I chose the HSR 42 Mikuni. With my new carburetor in hand, I removed the intake manifold and welded a piece of intercool piping so it would fit properly. Master fabricator (and my boss), Joel Rodgriquez, designed the intake box for the turbo with a blow off valve on the top; which gives it a clean look. The exhaust manifold, my own design, took 8 hours to tig weld, having to make many tacks on and off the bike before finally welding into one whole piece.

Because of its size and how cheap they are, I chose a GT-15 Turbo. This particular GT-15 has an internal wastegate set at 5 psi; which is plenty of boost for my bike. I then needed a flange for my downpipe, so I texted a picture of the turbo to my friend, Tiny, and by the very next day he called to tell me it was already completed. He’s the best machinist I know, hands down!

The downpipe was my favorite part of the bike to make. I started to bend and shape the pipes to get the look I was going for. I wanted to do something crazy, so I decided to make the wastegate go up and down and cut it at a 45 degree angle. I call this downpipe the ‘Flamethrower,’ because you never know when your turbo is going to spit flames!

Every turbo is oil cooled and in some cases they are oil and water cooled. The one I used is the oil cooled type, so in order for me to get oil, I removed the oil pressure switch and added an oil feed line. Once you have oil feed, you also need oil return; so I just simply tapped into the cam case to make that return work. Speaking of the cam case, I wanted to make something custom for my points cover. After finding a blown-up turbo lying around the shop, I removed the damaged compressor wheel and bolted it to my old cover. I then rattle canned it gold.

Since I’ve always liked the look of an old-school chopper, I chose to go with a classic springer front end. After installing the springer, I noticed that moving the bars hit the tank every time. To fix this, I chopped up the old stock sissy bar using it to make brackets that would lift up the tank.

I will admit that most of the money I spent to fix up the bike was my splurge on wheels and tires. The front is a 21” gold mammoth fat spoke wheel and the rear is the 16”. It’s my opinion that these mammoth fat spoke wheels look awesome with the whitewall tires.

The original Sportster 1200 came with a belt drive, so I switched it to a chain drive. The chain drive has a 21 tooth front sprocket and a 48 tooth rear sprocket; then I installed the gold chain. To get the rear fender to look like it does, I had to cut the stock fender in half, remove the brake light, then tig weld a piece of stainless steel to cover the hole of the brake light.

Last, but not least, it was time for the icing on the cake…the paint job. Dave Lyons, a close friend, master mechanic and president of Kustom Kreationz Car Club, was up for the challenge. The gas tank, oil tank and the fender that I had modified were all about to be transformed from bland to grand as Dave spent hours on the body work. By sanding and adding filler, everything started to look perfect; especially the fender which you can’t even tell was a stock fender in the first place. We chose a black base coat and mixed red and gold flakes in the clear coat to make it sparkle, painting it in the carport outside. That’s what I call backstreet bike building at its finest!

Thanks to all of my friends and family that helped me with this build. See ya’ll on the open road!

Bike Owner: Andrew James
Lisa Vaquera
Model: Renee Carlson

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