The forks are completely hand made by Kayaba and the lower sliders are carved from billet. The front suspension provided excellent performance and worked very well with the chassis design. At the triple clamp contact points, the fork tubes are knurled for a better grip and they are turned down on a lathe between the upper and lower clamps for less weight. The complete fork assembly is very light. It was reported that one set of OW27 forks cost more than three YZ125's. The front brake arm at the backing plate is made from drilled steel for more positive braking. In the second photo below you can see how the return coolant hose attaches to the steering head.

The front wheel is the typical works Yamaha design that was used from the early 70's with a magnesium hub laced to a DID rim. These set the standard at the time for braking power and light weight. The same basic design was carried all the way into the early 80's. Notice the beautiful machine work on the aluminum slider in the photo below. Fans lined the fences just to look at the bikes that carried these parts. Two photos down you can see how Bill Buchka made sure the brake cable stayed out of the tire. He used white tape that would be wrapped around the dust wiper twice, then the cable was put in place and then wrap it around several more times. He always made sure that each time he wrapped the tape around, it was wrapped exactly over the previous tape to insure a very neat look. Bill was very meticulous about his bikes.

The rear hub is an extremely light weight conical design that is sand cast in magnesium. The backing plate is a die cast magnesium stock unit and together with the rear hub provide a very light weight rear wheel. All the un-sprung weight on this bike is kept to an absolute minimum. The tires on the bike are Trelleborgs. Bill had much experience with Pierre Karsmakers and the other European factory Yamaha riders and it was from their influence that Bill selected Trelleborgs much of the time for Bob.

 The rear shock is completely handmade by Yamaha. It uses 2 springs for progression and also features a thermostat inside the shock that adjusts (closes) the damping as the oil gets hot and loses viscosity. This was experimental and initially didn't work as well as hoped. At Midland Michigan, Bob had troubles with the rear shock in the second moto when the shock failed and lost all damping. When it worked, it worked great. The cost in 1976 dollars for one shock was around $5000.00. Compare that to the cost of a complete 1976 YZ125 motorcycle at around $900.00.

Most of the bolts that aren't titanium are machined steel as you can see by the drilled steel bolt on the torque arm above and the footpeg bolt below. Only some of the small 6mm steel bolts are standard. Below, Bill wrapped the brake pedal with a piece of rubber as a stop where it met the clutch cover. Space and weight were saved with the way the rear brake pedal is mounted by actually sliding over the kick start shaft.  There is a brass bushing pressed into the pedal that is dimpled for grease to set in and provide a very well thought out set-up. The rear brake pedal has a very solid feel to it that you only get on a works bike.

Bob used a Magura front brake set-up exclusively in 1976. These were the same as what was on his Husky before he was a factory Yamaha rider less than a year earlier. Below is a set of works air-caps that Bob did not use on this bike as well as the machined top triple clamp. Bob used a cast top clamp, the machined  lower clamp that you see below and standard fork caps with no air. The pinch bolts are billet titanium.

The gas tank is made from very thin but very strong aircraft quality aluminum and is by far the lightest gas tank I have ever seen. Below the side panels are made from a translucent polypropylene plastic. In 1976 pro riders were ranked and you were either an expert pro (ranked) or a novice pro (unranked). Expert pro's used white number plate back grounds and novice pros used black number plate back grounds. Bob was  novice pro in 1976 as it was his first full year and Bill pop-riveted black Cal-Custom plastic number plates to the works side panels. As a pre-caution, he used Japanese brown duct tape to keep the side panel to the frame.

At the top of the steering stem, is a fitting that the coolant passes through to return to the radiator. The mix was 70% distilled water and 30% antifreeze.

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