| The swingarm Inspired by the oldskool US dragbikes I wanted to create an "outrigger" swingarm, with the two main beams running straight on the outside of the frame. But these swingarms aren't designed nor suited to be used in combination with suspension but for use in combination with rigid struts. I had a 1100EFE swingarm laying unused in my garage so I designed the swingarm to use these bearings on the inside of the frame and a loose-fitting bushings on the outside, because it's almost impossible to keep the three separate bushings perfectly in line during the welding process. |
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| This is the drawing of the main construction, made in AutoCAD LT. |  |
| A colleague at work made a 3D SolidWorks model of the swingarm. The program could also calculate the weight... 8,8Kg to be exact. |  |
| This is the raw material cut to the exact length (which took a few attempts from me to get it right :-/ ) |  |
| It must have been almost fifteen years ago since I last touched a milling-machine but the slots from the rear-axle came out perfect, even though I had to make the 20,2mm slots using a 19mm bit. |  |
| Here the middle tube has been machined to accept the EFE bearings and dust seals. |  |
| The most critical step in the fabrication of the swingarm
in the welding. At first we were thinking about tack-welding the complete
construction to the workbench to stop it from warping, but I was afraid
it would just build up tension when welding it all on one side and
warp as it was released. We put a 28mm solid steel rod trough the bushings and welded an angular profile on the outside to keep them spaced correctly. Then we tack-welded the construction together. First Ruud welded all the vertical welds while I kept flipping the swingarm over to make sure the heat-buildup was as spread as possible. Then we did all the horizontal welds the same way. This method worked out great as there was no sign of any warping at all after the swingarm had cooled down. |
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| Ruud tack-welding everything together. |  |
| Me removing the angular profile after the welding for the test-fitting. |  |
| And fit it does, though it takes some convincing of the outer bushes to pass the frame beams. |  |
| Job done :-) |  |
| This is the bronze bushing that supports the outriggers. |  |
| Fitted into place. |  |
| And an additional spacer. |  |
