Yes, these are not standard american threading. Which I could remember the thread measurement.... One of the tricks I use in a pinch is to pick up the cheapest asian kid's kit I can find (like First Act) & salvage the T-rods.

Your best bet is to just replace the threaded inserts inside the lugs with modern ones so they can accept modern (and readily available) tension rods. Most of the MIJ stuff I run into will accept a new, modern threaded insert with no problems. It's much easier to do this than scouring around trying to find odd thread tension rods. Lug inserts and tension rods are inexpensive as well. It may not be "all original" but I think this, at worst, is a very minor offense. Besides, what good is a drum if you can't even mount a head on it?

I've seen several variants in the older MIJ kits with metric tension rods:

The most common threading is 5mm. x .8mm. Occasionally 5mm. x .9mm is found. The first thing you might do is acquire a pocket metric thread gauge from a good hardware supplier. Very inexpensive, small enough to fit in your pocket or gig bag. Measure the threads (my guess is they're 5mm. x .8mm) to know for certain what you're needing. Most long standing music retail houses have boxes of miscellaneous parts which usually have some of these rods. Other sources would be to buy as cheaply as possible kits or spare drums from which to borrow the rods. If all else fails replacing the threaded lug insert receivers with standard 12-24" parts and rods is workable but quite a pain! Eye Ball

Good luck! Remember that the hunt is usually more rewarding than the trophy!

Fastenall stores have thread gauges to tell you what you are dealing with. Seems too new to be metric, but I did own a Yamaha set from that period (the inexpensive line) with metric rods. Replacing the inserts is the easiest answer.

Yep, as mentioned..find out what the thread is and maybe you can find them online. If not, as mentioned, replace the swival nuts if you can find some with a common thread (non metric) that fit into the lugs. Replace tension rods that fit the swival nuts.

I second this.