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I'm rethinking the pin in the head tube. It's easy enough, so why didn't the original swing bikes do it that way? I suspect the weight of the cranks and all might be too much to hold at that spot. Then add the force of pedaling and it seems like that spot where the pin would go through would take too much stress and something would give out or crack.
A brace like the swing bikes used looks like the best way to go. I'll go through my scrap and see what I can come up with.

01 May 23 sbike - Copy.jpg

26 May 23 mockup - Copy.jpg
 
I have a section of bar left over that is just long enough to work. I'll bend it into a U shape. It will bolt to the braces and then get pinned to the lower frame bar. The pin will have to be inserted from the bottom. It should give more strength like this.

26 May 23 mockup - Copy (2).jpg
 
The lucky 7 chain rings are 36 and 42 teeth. When I'm in swing mode, I think a lower gear ratio will be needed. Once I'm locked in, I can probably go faster and the higher gear will be good, but still lower geared than a regular one speed.
I'll have a 46 and 53 gear index with this setup, a 16 tooth cog. A tensioner will take up the chain slack when I'm in low gear. Shifting is manual.
I had this type of setup on another build way back when but I think it was a coaster brake, so it wouldn't work. I've been wanting to try it out ever since.
 
The drivetrain was easy and works well. Pics of low and high gear:
29 May 23 low gear.jpg


29 May 23 high gear.jpg


The shiny chrome faces of the chainwheels are facing each other, but that's the only way it will work.

The band brake needs a larger bracket to attach to the rear fork. It is made for a chain stay. I'll have to fabricate something.
29 May 23 band brake.jpg
 
This morning before breakfast I swapped the frame around. The front looks better but there's a big problem. The seat is too high, even at it's lowest will be 38" high. That's about 6 inches too high.
With the tire at 26" and the head tube at 5", there's no way to lower the seat.
View attachment 232776I have a 24" wheelset, but that's only 2 inches lower, not enough. I'll try a 20" wheelset later to see if that might work.
As I’m building a 24” frame Raleigh…. This thing looks FINE! :)
 
I did some bar bending and drilling. I have no specialized tools for this, so it was the vise and elbow grease. I looked at some old fenders but they weren't right, I need some Stingray type fenders like the originals.
30 May 23 bend.jpg


The bracket is in there, but isn't going to hold the cranks solidly, there's a little sway. That is okay because I will mostly ride it in swing mode. The locked in mode will be needed for parking and transport on the bike rack. The pin is 6mm and can be stored in the rear fork brake hole (where I have an extra pin). I need to trim the ends and paint the bracket. I haven't made a final decision on which seat I will use.
30 May 23 brace1.jpg
 
One month in, and it's ready for a test ride. I got the brake hooked up and everything tightened up. By pure luck, the riding position is perfect for me, like sitting in an easy chair. I'll ride this whether I learn to swing or not.

01 Jun 23 rtr.jpg
 
One month in, and it's ready for a test ride. I got the brake hooked up and everything tightened up. By pure luck, the riding position is perfect for me, like sitting in an easy chair. I'll ride this whether I learn to swing or not.

View attachment 234871
Just be brave and try to swing it. It will put a big smile in your face and the faces of the people you pass by with it!😁😁😁

It took me about half an hour to learn to basically handle it. From there on it's just pushing the limits bit by bit.🤘
 
I was hoping for a ride, but the brakes won't give enough stopping power and the chain is skipping.
I can't figure out why it has a skip. The chain is in alignment and doesn't skip unless I am pedaling.
I have one more disc brake conversion kit that I may use, or add a second caliper brake.
02 Jun 23 brake.jpg
 
I was hoping for a ride, but the brakes won't give enough stopping power and the chain is skipping.
I can't figure out why it has a skip. The chain is in alignment and doesn't skip unless I am pedaling.
I have one more disc brake conversion kit that I may use, or add a second caliper brake.
View attachment 234988
I would guess that the chain starts to skip probably due to some flex just behind the BB, as it "hangs" on a single tube only. Maybe another set of brackets going from the BB to your diagonal or to the rear fork could do the trick?
 
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The chain skips somewhere near the tensioner and cog. I don't see any flex with the chain stays, I had reinforcement plates welded on top and bottom to the BB and chain stays. I'll try it without the tensioner and see if I get the same thing.
 
I did some research and found a bunch of info on the same thing. Chain wrap was insufficient, there wasn't enough chain on the cog. But I don't need two low gears anyway so I solved it by just using the 42 tooth lucky 7 chain wheel. I was able to ride it in circles in the shop! It will turn even sharper in swing mode later.
02 Jun 23 drivetrain.jpg

Then on to the disc brake, I can't find the bracket that attaches it to the fork leg, so it's on order with another kit.
 
I did some research and found a bunch of info on the same thing. Chain wrap was insufficient, there wasn't enough chain on the cog. But I don't need two low gears anyway so I solved it by just using the 42 tooth lucky 7 chain wheel. I was able to ride it in circles in the shop! It will turn even sharper in swing mode later.
View attachment 235003
Then on to the disc brake, I can't find the bracket that attaches it to the fork leg, so it's on order with another kit.
Can't wait to see you riding this thing in full swing! :thumbsup::cool:
 
While waiting for the disc brake kit to arrive, I used the hub adapter that will unscrew itself if you brake while rolling backwards, but I can live with it. I mounted the last rotor I had and now just need the adapter that attaches the caliper to the fork. I had to add a spacer to the axle for the rotor to clear the wide fork leg.
04 Jun 23 disc brake.jpg



I don't like the previously modified center stand so I ordered a new one, only a different style. This pic shows the plate I had welded to reinforce the BB. It has the same on the bottom so it is solid.
04 Jun 23 stand.jpg
 

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