I have always had an insatiable itch to modify, customize or tweak everything I own. I will look at something I own and see how I feel it ‘should’ be and if I don’t make it so, it will torment me. This was always the case with my BMW R/75. Don’t get me wrong, I have done a lot of work at that machine, but I never went ‘all out’. The BMW has always been the trusty stead that brought me and my girl around. However, that always meant I couldn’t chop the frame and put a solo seat in. In other words, I couldn’t fully cafe the bike, so I had to settled with a partial cafe and vintage mod. I love the BMW, but I always wanted something more custom.
Shortly after moving into a house in San Francisco with a large garage, I began thinking about a new project. One day I get a text from a friend linking to a Craigslist ad for 3 rusty and incomplete early 70s cb450s. The task of converting all that into a complete and running bike seemed incredibly daunting to me, but I was easily persuaded and the next thing I knew, my garage was filled with rusty parts.
The bikes were taken entirely apart. Each part was sand blasted and polished, or powder coated. All in my garage on a shoestring budget. I DIYed a sandblasting booth using a Rubbermaid bin, a $30 sandblasting gun, and a $75 used compressor. For powder coating, a $40 Craftsman powder coating gun, and the largest used toaster oven I can find. The toaster oven was perfect for anything that can fit in its 12″ x 12″ space. For larger things I got a little more creative. I definitely do not recommend doing this, but I made a wood box large enough to fit a motorcycle frame and lined the inside with sheet rock rated to 220 degrees. The sheet rock was then lined with tin foil. I made a manifold out of a steel pipe that connects to a propane tank. The steel pipe was drilled to allow the propane to flow through. When lit, it created a great heating source. To avoid direct flame from hitting the actual parts, I used a metal rain gutter guard as a shield to place over the open flame. With some tweaking, I was able to get the oven to 350 to 400 degrees! Did I mention the sheet rock was rated to 220?
Polishing and powder coating are very meditative processes. I found a lot of joy in taking something old and rusty and making it look as new. Its very convenient to be setup to do both of these processes in your own home. You can then powder coat any piece you want any color you want it. This can allow for an OCD level of color control and coordination, down to every bolt, washer, or nut. I wanted a darker color scheme but wanted to stay with natural tones. The frame was powder coated a dark bronze while the rest of the bike was either flat black or polished aluminum. I used a dark brown distressed leather for the seat to compliment the bronze. The tank straps were re-purposed from a 1940s WWII era German messenger bag.
I taped up the engine and sandblasted it while it was all together. The engine seemed to run well, so I didnt want to tear it all apart. Since it wouldnt fit into my sandblasting rubbermaid booth, I tipped my powder coating booth on its side, placed the engine inside and crawled in the sandblasting gun! This was another thing that I would not recommend. I had a beautifully clean engine afterwards as well as a crick in my back that lasted a week and half.
The tail end of the frame was cut off and I welded a raised platform that served as the base for the seat pan as well as the mounting area for all the electrical components. I used a full size battery and relocated it to fit very snugly under the seat hump. I had to raise the platform an inch in the back, to allow enough clearance for the wheel to not rub if the shocks get fully compressed. I used a piece of wood to act as a spacer to raise the fiberglass seat pan up to line up well with the tank. It was important for me to have these lines match up for continuity. Im referring to the back of the tank and the seat hump. I feel that if you draw an imaginary line continuing from the top back of the tank, it should meet with the rear seat hump. This makes the bike look balanced. With the pipe sweeping towards this direction as well, it makes the your eyes want to move towards the back of the bike.
Performance wise, this thing is a beast. I can see how this bike dominated the circuits when it first came out. It has some great pull and handles very nice. I consider the bike finished as it looks clean and runs, but projects like this never fully end. I will be upgrading to an electrical ignition and upgrade its charging systems. I have a few aesthetic details I still want to add, but for now this bike will be spent on the road more than on the bench it lived on the last few years.