The Frame Game...

By the time you read this, the beauty pictured above will be at Salon Prive; but how was the frame made? Allen tells all...

- Allen Millyard

I had recently finished making the six-cylinder engine and wheels for my RC374 and I was really looking forward to getting on with the frame.

Before I could start making it, I needed to finish modifying the forks, machine up a head stock and make a swingarm. The lower fork modifications were completed when I trial fitted the hub which involved welding on new brake anchor points, removing the lower mudguard mounting lugs and reducing the length of the fork seal holders, so I just needed to shorten the fork tubes to make them the right length. To do this I cut 40mm off the top of each fork leg, but in doing so, also removed the internal threaded portion that is used to secure the forks to the top yoke. I was able to re-use the two bits of fork tube with the internal thread by machining down the outer diameter until they were a push fit back into the top of the fork tubes then I welded them in place.

The bottom yoke was cleaned up to remove unwanted casting ridges, lugs and the steering lock. I then cut off the raised handlebar mounting lugs from the aluminium top yoke and welded up the two holes that were left behind. Finally I dressed the surface with my Dremel and rotary burrs to produce an ‘as-cast’ looking finish. The next job was to make the head stock for the frame so I ordered a piece of thick wall steel tube and machined it on my lathe to Honda CB77 internal dimensions and overall length but to look similar to the RC174 on the outside.

Once the head stock machining was complete the CB77 bearings were pressed into the head stock and then assembled in the yokes. The forks were then placed into the yokes followed by the front wheel, to complete the front-end sub-assembly.