jc higgins headset size

[scale]

I have a flightliner i am rebuilding and the headset cups are trash. I need to replace them. They measure 34mm and i cant seem to find any headset that will work. Is there a go to headset for 1 inch forks that have 34mm cups? I know wald mades an oversized headset but it is only 32mm or so. also...i know you can get adapters / reducers but they are $20 which is a bit nuts.

 

[Barking dog]

I have the exact same issue with a Murray Sonic Flyer I’m trying to bring back to life. Many searches in Google, eBay, Rat Rod Bikes and here have revealed no “over the counter” solution. I have seen references to head tube shims to make 30mm set fit but I can’t find a reliable source. No solutions just yet, I guess I’m just commiserating with you. Good luck!

 

[Archie Sturmer]

Promax may be reliable, and is one source.
http://www.promaxcomponents.com/product/ha-1-headset-adapters/
Ebay may be reliable, and a preferred source to some.
https://www.ebay.com/itm/PROMAX-BMX-PRESS-IN-HEADSET-ADAPTOR-1-1-8-1/401602983060

If you have a 34mm (MTB, cruiser, or other) headset, you may wish to check the fit (and measurements) before you buy; there are 3 outcomes - too big, too small, or just about right. And the 34/30 adapter shim is used with a 30 mm road bike headset, not a regular American bike headset (1-9/32").

At one time after searching online, I found a headset part number NECO H833K and drawing that matched 34 mm cups with 1"-24 forks, but could not find anyone who actually sold them, but then I didn't call the company headquarters (NECO) in Taiwan; I did not click the link to "send inquiry".
https://www.necoparts.com/en/product/External-Cup-Threaded-Headsets/H833K.html

My preference is the cheapest (including time) and quickest solution. I also prefer standard parts, with adapters as necessary to fix the problem part(s).
If someone else (or myself and if I forget), disassembles the bike in the future, the adapter would stand-out a physical reminder that the bike has a special part, but it might look just like any other. Custom parts need heightened configuration controls.