Expresso Swingarm

When we start a new custom, there is a tradition that we respect religiously: We always start with what seems to us the most difficult part to fabricate. So, on this Monday morning, the swingarm is the first part of the bike that we lay down on the fabrication table. (a.k.a. the surgery table) The first decisions to make are:

1. The number of steps inside the swingarm.
2. The thickness of each step and which one is thicker (top or bottom?).
3. How the swingarm must look from inside.

It's my job and responsibility to make these decisions, but I would never obligate my fabricator to do anything without first convincing him, if necessary. Bob is in charge. He agrees immediately with me on the fact that: Steps always look better in odd numbers, so we keep the three steps as they appear on my sketch; The step on top will be higher. Each step must be about half the size of the one just above (to give fluidity to the lines), but the thickness of each step must look the same (as a matter of fact, they have to be a different thickness because they're welded to the same back plate); Seen from inside the swingarm, no step will be visible because it would visually interfere with the wheel and brake designs.

Our "stock" swingarm is thick. It takes almost an hour for Bob to cut the pieces joining the main tubes of the swingarm -- just the time I need to cut cardboard templates of the steps. It's from these cardboard pieces that Bob cuts three metal pieces that he will adjust inside the swingarm. Then he will duplicate (reversed) these three metal steps for the other side of the swingarm. It's already 80 degrees at 10 a.m. Bob has a lot of cutting and welding to do and he is already sweating. We close the bay and set the air conditioner at 75. I leave the fabrication room to work on a new chopper that I have to get started. But that's another story... Bob and I have an agreement: I never come to check what he does. If he is stuck with a problem, he calls me immediately to decide a remedy. But if everything goes fine, he calls me only when the job is done and looks perfect to him. I estimate that the swingarm fabrication is a two-day job, including the cutting, trimming, welding and polishing. Good news -- I won't hear from Bob during these two days, and will resist to the temptation to check the work in progress (which is, for me, very difficult).

Two Days Later

Expresso gets its racy swingarm. We prime it because I hate to see a bike rusting during the fabrication and mockup process. To be sure it's perfect, we attach it to the frame using Progressive suspension shocks. I immediately see a small imperfection that nobody saw before -- a small bump on the lower part of the swingarm, just behind the rear axle. We correct it with a grinder and make a primer touchup. I already dream of mass producing this swingarm in steel or maybe billet aluminum. There's a typical builder's dilemma, however: How many need to be CNC machined to make it affordable to the public? How much money can I invest? Low cash flow has always been a custom builder's main problem...

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