Finally found that the c-clip and washer were absent from the post that holds one of the advance mechanism weights, allowing the weight to wander along the shaft, and potentially binding. The clip and washer from a used points set fit perfectly, and greatly reduced the idle problem. Another thing that may have helped was cleaning the rust from the pivot shafts and applying some dilectric grease. There were also some poorly done wire splices and a crack that got some solder and heat shrink.
Still pretty rough. A lot of things could be done to make it more correct, but where do you stop? The owner was after a reliable rider, so the roughness allows you to ride with some abandon. The Mikuni 32mm carbs came from Dime City Cycles in a complete kit that had intakes, carbs, filters, and cables. A good bit of trimming was necessary to make the stock covers fit. The bike had an oozing dent in the magneto cover and the twisted shift pedal that went with it that was repaired by a used replacement cover and some heating and bending on the shifter.
What hey call “a twenty footer.” Looks pretty good from twenty feet.
There were some shorty headers with some heinous welds on them when the bike arrived at the shop that were swapped out for a set of used ones. I don’t know how it sounded before, but they sound like a proper Honda now.
On Calvin’s 1978 Honda CB750 conversion, new swingarm bushings were machined from DOM steel tube, and some work was done on the tank. The end of the tank tunnel needed to be covered, or the seat pad needs to extend upward to cover it. The seat rising up did not sound like a good look for the Cafe seat, so a metal cover was the solution.
A thin steel cover was welded in extending the tank character lines as well. The tank edge was heated and bent downward in line with the new panel, and then welded only on the outermost edge of the tank’s pinch welded seam, to keep from having to weld the tank skin directly.
A soft dent in the tank got some attention. This is the before. Looks like someone started to work on it and gave up. Probably best they did…I have seen one inch Bondo before.
After some studs were welded on allowing the dent to be popped out with a slide hammer. Because the paint had been ground off and left to rust, some suspicious spots looking like possible pin holes were present. The inner tank is extremely rusty and only after cleaning will the extent of the damage be known, but an epoxy liner is going to probably be a good idea.