Some time ago I had to stop rebuilding carburetors for Honda models whose ignitions are contact point based. The problem isn't the bikes, it's the owners who have no idea what it takes to tune them. The carburetors are only a piece of it, and not the most important one. Folks unfamiliar with point ignition have no frame of reference with which to comprehend the vital importance and serious implications of neglecting their ignition systems. Ignition timing is an art, and though not difficult for an experienced person, the process is unintuitive. There is real angst waiting there. As a result, vintage customers go "deer in the headlights" when you try to educate them. They don't have a clue and they don't want to, and it is virtually a guarantee I'll hear back from them that the "carbs aren't working right". If that weren't enough reason to stop rebuilding SOHC four and GL1000 carbs, and it unfortunately is, there is also the recent disappearance of jet needles and needle jets for these carbs, the highest-wearing parts. They're gone. All of them. This means that about half of these carbs cannot be properly rebuilt. And that's not even considering the float valves. $300 for a set now.

The same culture of dispassionate indifference about ignition care prevails in all other areas of vintage maintenance. Unlike modern vehicles, 1970s Hondas demand constant diligence to maintain mechanically, and restoring long-neglected machines to good running condition requires a level of effort that few are prepared for. Because as important and as pivotal as ignition service is on these machines, there is much more than that needed on the. So, carb work, sure they need. But ignition work too. And a lot more. Invariably.

Part of the problem is these machines have so little value no one wants to get them serviced correctly. Vintage Honda motorcycles are expensive to repair; quality parts (as opposed to Chinese crap) are hard to find and cost dearly. And it doesn't help that even just a major service equals what the bike is worth. Vintage Hondas are too little appreciated by the market and too neglected by the average person. Not a good situation and very real.

This then is the environment that the 1970s Honda exists in. The kind of maintenance it typically receives simply furthers its neglect. The bike is perpetually in need of repair. Its value remains low and the sticker shock of professional repair increases. And sadly, the individual almost three generations after the original purchaser is at least that far removed from understanding.

Recommended reading:
The GL1000 problem
Why No Love?