Hello from Tunbridge wells

A motorcycle usually has a swing arm at the rear and forks at the front, in this case we need a swinger at both ends…..

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this first image is the matching of the tooling to bend T45 oval tubing, this was very problematic I did it cold, filling the tube with sand and making a rocking arm fixture that stretched the tube in small increments.

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after several attempts I got these.

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Front axle boxes
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weld in the ends
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embryonic swinging arm

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Front and rear swingarms, after powder coating, I can’t find more pics of the fabrication.

I came across a few more pics of the swingarms.

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here they are test fitted to the chassis
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this image has the gen2 engine, and tail side plates, nominal wall thickness here is 2.5mm

The above post has the yoke fitted, centre hub don’t have forks, but it needs steering, I decided to keep this as normal as I could, so top yoke, but using a tapered splines on a hollow shaft, as a steering stem to transmit the torque from the handle bars to the drag link at the bottom, these splines are designed so I could machine both the internal and external on the CNC mill, loosely based on a torques fastener, or “Hexalobular” :)

First images is the 3d model.
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Splines also on the drop down stumps that hold the bars

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Top yoke

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Nuts

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Splines

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yoke before fitting, bearings are angular contact.

Beautiful craftsmanship!

I designed my centre Hub steering system around using an existing wheel, from a Yamaha, I bored out the centre section and made a central hub located via the brake disk fastener points, the hub is billet aluminium, spindle is EN 24T, as is the offset kingpin, this is supported by tapered roller bearings which are preloaded.

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2 of these carry the wheel bearings and brake discs.

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rough turning the hub

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CNC machining the hub, and thread milling the bearing adjustment area.

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Hexalobular again this time on the end of the spindle, this for the upright that links the swingarm to the top drag links forming an adjustable parallelogram, this allows adjustable castor angle.
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boring the kingpin location.

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this is the finished hub

In this bike there was a lot of CNC stuff, but also quite a bit of more traditional fabrication, the tank etc are hand made without a buck, sort of free hand, in part because I knew this bike was a one off, for me it was an exercise in engineering, at this point I was working more or less alone in my home workshop, this is all pre SNT.

this is making the panels for the tank before tacking up.

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making the fuel cap
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finished tank riders eye view, during an early test.
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Here’s some other bits I made for this project.

Water pump, because the port was in the wrong place.


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Radial brake and clutch master cylinders

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Radiators the cores where supplied by Pace.
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The radiators work on the principal of the Meredith effect, behind the rads I created an aero foil, which creates a low pressure area behind the rads sucking air through them, I was unsure if it would work but it appears to, the fans only come on in traffic.
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this images is the day it was first ridden.

Fascinating and deeply impressive stuff there!

Interestingly, I once went out with a girl called Meredith who had an amazing sucking effect on my bank account, but for very little positive outcome. I shortly had to abandon the project while I could still afford to feed meself :)