I'm looking for a 9989 Spark control coil clamp to buy or borrow, or failing that, photos/dimensions for making one (Old Dude doesn't have them). My bike had a magneto when I got it, with an aftermarket advance/retard handle attached - so no adv/retard cable, so no clamp.
Parts Catalogs - I could not find this in the 53-56 Spare Parts Catalogs. I did find it in the 1957 and 1959 catalogs - only in the text, not in the illustration. Apparently when they updated the Handlebars and Controls section with the new Sportster 56628-57 Timer Cable Bracket, they realized they had left the K-model clamp out. Interestingly, they list the clamp as fitting 54 to 56 Model KH. I suspect this is also used on 52-53 K.