BO15 32 Motorbike

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I will be building a bike from scratch that's inspired by a '40s Schwinn Motorbike. At least, I think it's 40s, I'm not an expert. It doesn't really matter anyway, and it will not be an exact replica. So, if I'm shooting for 1940s, why is 32 in the name? Because I am blowing it up to scale for a set of 32" wheels I got from a Walmart bike some years ago. My sheet metal skills are limited, so I'm not sure how far I will go with a tank, etc., but I have an idea on how to do some big fenders, and a simple chain guard. It may end up with a simple tank plate. The whole point is a vintage looking bicycle that fits me, without having to stretch it, or lay the seat back, or anything.

Here's the template that my wife and I made, which took something like 60 pieces of paper that we printed, and stitched together.
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And once I glued what I needed to a piece of plywood, I got started on the frame.
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I'm not sure how I'm going to do the forks yet, or many other things, but we'll see how it goes. I'm also aware that the picture of the bike is not a direct side view, so the frame may not be 100% correct, but it'll be close enough for all but the nit-pickiest of folk.
 
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I really wanted this bike to have a blade fork, so I had two options. One would be to buy some 1/4" bar steel, and try to bend it all to shape, then cut it to a taper, THEN heat and give the ends a bend. That would have resulted in a more proportional fork, but I went with option two. I took two blade forks, and put them together to make one three inches longer for the larger wheel. It may make it look small or wimpy compared to the rest of the bike, but we'll see. I think I'll call that good enough. I'll add some truss rods, and hope the overall effect works well.
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I've also decided to TIG weld it all out using silicon-bronze filler rod, which will give it a bit of a brazed brassy color to the joint connections. You'll notice that the chainring is not to scale. I made that choice for now, both because I sold all of my 65T chainrings, and because I want to make this thing easy to pedal. I could add a large cog in the rear, as well, but that all just seems a bit unnecessary.
 
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This build is so cool, digging how your ‘upsizing’ it whole maintaining the use of the stock tank
I don't have a tank, so I think you're seeing an optical illusion with the printed template.

Awesome, but I don't know if people are getting how big those 32s are. Can we get a 26" wheel in the picture for reference?
I'll definitely pose that photo soon.
 
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In my attempt to make the chain stays, I had issues. I wanted to give them the slight bends outward from the BB, as you see on most bikes of that era. First, I tried just heating them up and bending them. Nope, wrinkled too badly. Next, I tried the old "fill them with sand" trick, heated them up, and bent them. Almost looked exactly the same. Finally, I just bent the tubing with a conduit bender into a 90, then chopped and welded it. That solution would be more described as "curves" rather than "bends," but it got the job done, and I actually ended up really happy with how they looked, especially after I gave them a slight curve upward on the middle of the stays, and joined them together.

See from left to right, heated, then filled and heated, and third is chopped up from a bend. It burned up 10 feet of tubing to get it right, but these things happen, I guess.
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Here's the final set of stays:
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