Float valves
When I began doing carburetors full-time I tried using aftermarket float valves. They were uniformly bad. I began testing brand-new ones right out of the package with a Mityvac before installing them. The result was I had to throw half of them away. I had to buy eight to get four aftermarket valves that would seal. Sometimes ten. And then, more often than not, even the ones that sealed initially quit sealing after a short while. And if that didn't happen then the plating that is put on these crappy float valves would begin to peel, resulting in carburetor overflow. One hundred percent of all new factory Keihin float valves pass the vacuum test. Every one, steel or Viton. The first thing a carburetor customer looks for is fuel tightness. I'm going to send him carbs I know are going to leak? Hardly. I can't understand why anyone would use these parts, especially people who rebuild carburetors for a living.

I like rebuilding carburetors for machines I am the most familiar with. That is, I know 70s and 80s Hondas well and I like to think about these bikes as I do the carbs, knowing where their weak points are and how in some cases they can be overcome with small carb changes. You may think that approach is assumed, taken for granted. But I can tell you nearly all carb rebuilders out there are clueless about the bikes belonging to the carbs they work on. They know nothing about them. And an astonishing percentage of these folks know very little or nothing even about motorcycles in general. Honda is the only one of the Big Four that still makes available vintage OEM float valves. If I can't get factory float valves, I won't rebuild the carbs. I won't make excuses. This is why I don't do older Kawasakis, or any Yamahas or Suzukis. There are no float valves available for them. I don't want to make excuses to my customers. What a terrible thing to have to do. And it's got me thinking. Why aren't the rebuilders who use K&L, Keyster and Napco float valves making such excuses? Why aren't their customers being warned that the carbs could overflow at any time? It's perplexing to me. Maybe most customers fail to maintain their carbs from one season to the next, and thus they never realize the poor quality parts that are in there, chalking up eventual leaking issues to "it's time to rebuild them again." And it's even more likely that most "professional" carburetor rebuilders just don't care.

Carburetor rebuild kits
These bad float valves are often found in rebuild kits. Certain forums have made an effort to compare different carburetor rebuild kits. I hope it instructs as instruction is badly needed. And I really appreciate the effort that goes into these articles. But why compare carb kits? Putting carb kits up for comparison is like having a farting contest. The problem is the subject is still a fart. There is nothing good about carb rebuild kits. For the life of me I cannot figure out the average consumer's fascination with them. Maybe it's the influence of the car repair trade. I dunno. But I know this, people within the industry have avoided them for seeming millennia, using instead quality rebuild parts from legitimate sources, including mostly Honda themselves. No reasonably competent carburetor rebuilder uses kits. They're extremely cheaply made, and more importantly, frequently result in that supreme tragedy, the ignorant tossing of perfectly good and very difficult to find OEM jet needles and needle jets. I deal with this issue almost weekly, having to inform my customers of the presence of Chinese or "high performance" metering parts in their carbs and the cost to replace them with OEM. The problem is OEM is pretty expensive because it's available only by buying whole used carburetor assemblies. Cannibalizing, in other words. That's expensive. The unavailability of carburetor "hard parts"--that is, mostly the metal parts, parts other than the widely-available gaskets, o-rings, screws, jets, and seals--is the real world of vintage Honda carburetor rebuilding. And it's why I don't rebuild 1960s Honda carburetors.