Grant's Featherbed Special

After a few different attempts, this is what I came up with
 

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I went for something more angular first, but when we made a prototype out of wood, it just didn't look right.

This curvier one, I felt much better accentuated the curve of the rear frame loop - my favorite part of the bike!
 
So with the shape set, I set about working out what the dimensions should be based on those I had taken from the original swinging arm.

I came up with this
 

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Then we made a prototype out of wood, so we could try it on the bike, and see what it looked like
 

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I wanted to use modern suspension on the rear, to match my front setup, and really like the Öhlins shocks http://www.ohlins.com

Since I was building a Special now, i could get away with the piggyback canisters, which are infinitely more adjustable than the integrated units
 

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These units are from a Harley, but the internals (shim stacks) have been rebuilt to account for a bike that weighs significantly less, and a rider that weighs half that of what the Harley units were originally designed around.

The springs were also swapped out for lighter ones (the springs may need tweaking further)
 
So with the shocks built up, I could trial fit my wooden swinging arm
 

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In fact, I got a bit carried away, and buttoned up the rear wheel too

This is a WM4 18" Excel shouldered rim with 8 gauge stainless spokes built by Buchanan's http://www.buchananspokes.com

The rear tyre is a Bridgestone BT45 which is 120/90 in size

cNw turned the hub to remove the ribs - i think this is a really nice touch, and makes it a little bit different!
 

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Here is the rear end with the wheel fitted.

It's exactly the look I was going for, and the measurements worked out perfectly!
 

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So armed with a working prototype, piles of dimensioned drawings and a head full of ideas, i needed to find someone who could turn my wooden vision into metal.
 
After many calls, emails and discussions, i found a little engineering company here in England that felt brave enough to work with me.

We worked together, and eventually came up with this tweaked design
 

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Here is the swinging arm after the first bit of machining
 

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You'll see there are no holes are fittings yet
 

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Next up, it is mounted to the milling machine so that the slots for the adjusters can be made
 

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Basically, i didn't want any big adjusting bolts sticking out the back!
 

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Then we could set about the shock mounts
 

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We went through a few different iterations of this, but we agreed on something simple and flowing in the end
 

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I went for a Manx style bushing rather than the standard Metalastic bushing
 

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There is no distance piece between the bushings on these, although I can shim it out to stop the swinging arm from nipping up solid, if for whatever reason I get my measurements wrong.
 
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