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                              1976 Yamaha OW27 Restoration                      

   The restoration on this bike has finally started. I will be posting comments, photos and other info on a regular basis as time is an issue here to complete the bike. This is one of my favorite bikes and with the help of Bill Buchka and even a little help from Bob Hannah, we should get it spot on. Following the restoration there will be a full feature on the bike. Check back often!!!

     

                     The frame was sprayed with paint that is an exact color and shine match to the original color from 1976.

      

                                                              Swingarm is chrome-moly tubing and formed sections.

      

                                                          Note the spigot on the steering head for the coolant passage.

      

                                                                       Progressive works spring rate 1976 style.

      

                                                   Thermostatic monoshock was left untouched. Just a minor clean up.

      

Supply and return coolant passages through the steering stem are divided by an assortment of spacers and seals. The aluminum spacer on the center of the steering stem separates the supply and return coolant and has an O-ring that seals against the inside of a precision machined steering head. Inside the aluminum stem there is also a divider that separates. Below you can see the spigots on the frame. The supply is on the bottom. As the handlebars are turned, the hole in the stem will not always align with the spigot. There is enough space between the outside of stem and the inside of the head to allow ample passage of coolant. The stem is relieved at the return hole (above the alum. spacer) in the stem to hurry the hot coolant to the radiator. All this info is courtesy of Bill Buchka.

      

      

 The front and rear wheels were disassembled. Spokes and nipples were re-plated to an exact color match as original and new Trelleborgs mounted.

      

      

                       The airbox is very thin fiberglass with aluminum filter covers. This was cleaned and installed in the frame.

      

      

After the seals and the spacer (that separate hot from cold coolant) were installed in their correct location, the clamps were installed in the steering head. Note the original epoxy at the bottom of the lower clamp. On the top triple clamp, the spigot also serves as the steering stem nut. Original pinch bolts are billet titanium.

      

      

                                                                           The basic rolling chassis is complete.

      

      

A new seat cover will have to be made as the one that was on the bike was not original. When the old cover was removed, an interesting discovery was made. Bill had removed a section of foam from the middle of the seat and replaced it with a more dense strip of foam to make the seat firmer. This was to give Bob the feeling of sitting on the bike as opposed to sitting in the bike. Bill had performed similar modifications to Pierre Karsmakers bikes years earlier. It really helps to have the original mechanic around to answer questions. The seat pan is fiberglass.

      

With the tank and fenders installed, the rolling chassis is starting to take form. The better part of two days was spent enlarging old photos and scaling the stripes of the tank. The result is an exact match to the original, even the tank-strap crosses the stripes at the original location. The yellow paint match was taken from one of Bob's 1978 OW38 gas tanks as Yamaha's US works bikes used the same canary yellow from 1975 through 1978. When you take your time and pay attention to all the little details, it really adds up in the end. The original bars are out getting re-chromed.

       

 New bearings and seals were installed and the motor was bolted into the frame. Electronics, water hoses, foot pegs, rear brake assembly and miscellaneous hardware was also installed.

        

      

After searching through over a thousand vinyl patterns, an exact match was found. The stitch spacing was measured from a new 1977 OW27 seat and then duplicated when sewing up the new cover. Below, a new set of translucent polypropylene side panels were installed.

      

      

The tiny OW27 motor now has the carburetor, clutch cable, shift lever and chain hooked up and is now waiting for the pipe. Much more info on the motor will be added in the review.

      

      

Things are starting to take shape as the bike is nearing completion but there are many little details yet to take care of. Extreme care is being taken not to over restore the bike in any way. The goal here is to have the bike in the exact state that it would be in before a National in 1976.

      

      

The last details are now complete. I enlarged images of the side panels from 1976 photos and scaled the exact location as to where the rivets holding the black ovals to the side panels should be and did the same with the numbers. They are in the exact spot that they were in 1976. Other than the original bars that are still at the chrome shop, the bike is complete in the photos below. The bike will be in California where Bob will receive the "Edison Dye Lifetime Achievement Award" November 4th.

      

      

      

      

      

 The original number plate was hand painted by Bob's mechanic Bill Buchka. It was on the bike for all but two 125 Nationals (when the bike was air-cooled due to the claiming incidents) and remains in original condition as it was last used at the final event in New Orleans.