NUMBER EIGHT
His only disappointment was not being able to get blank Excel rims in New Zealand. Instead he opted for SM Pro blank rims, which he had drilled to match his custom made, machined from billet hubs. The hubs themselves were made locally, to a Maico design, but with backing plates specifically crafted to fit the Marzocchi Magnum 45 forks. The drum brake hubs have a much larger spoke flange diameter than a modern hub, so a standard pre-drilled Excel rim wouldn’ t have worked without kinking the spokes.“ It was dearer to buy them undrilled than drilled and then I had to pay to get them drilled on top. But I wanted it right.” Not satisfied with ordinary materials, many of the components are made out of titanium. The wheel spindles, some of the engine bolts and the fork bolts are all titanium. Many of the chassis bolts are custom-machined from either aluminium or titanium, depending on their individual strength requirements. Even the kick-start lever is a masterpiece of CNC-machined Ti billet. All up, the bike weighs in at about 114kg without fuel, on an even footing with a modern enduro bike.
As it sits, the bike stands in at over $ 25k, not including labour. That’ s not bad considering that a factory bike back in the day would have cost $ 60k to $ 80k, according to Peter. When he first got the idea for doing this project, a good, similar bike sold in the US for US $ 17,000 but as Peter says,“ Without blowing my own trumpet, it was nothing compared to this one.” The labour is the difference though. As Peter points out, it’ s easy to buy standard parts and bolt them together, but starting from scratch with things like custom hubs is a real mission. Peter had the idea to build the biggest capacity XR he could. This led him to the US and an Engine Dynamics USA 591cc piston / sleeve / gasket kit. With the Megacycle 144- 21 cam sitting in the head, it should rev to about 9000rpm. The modifications don’ t stop there; the piston is guided in its travels by a Carrillo rod, the oversized stainless steel valves are kept from bouncing with larger stainless steel valve springs, the rocker arms are hard-faced and there’ s a billet clutch to prevent any slip with the extra power and torque. All of the genuine parts were sourced new through Econohonda in Te Aroha.
Alloy tank is a work of art 591cc, Megacycle cam
Custom-machinedtriple clamps Machined from billet rear hub