MTFCA Forum

The side of my rear radius rod at the manufacturing seam (1925) is opening slightly near the fork. Is this sn issue that needs corrected? If so, what do I do to fix it?

Can you show a picture? Is it only on one side or both? Good used ones are found at most swap meets or members of your local club might be able to find you a good one.
Norm

That's not too unusual. You just need to be sure it's not being pushed open by rust, forming internally. When you state, "... is opening slightly...", it makes me think that it wasn't always that way, and that it's still progressing, which would sound like a rust problem.

Wire brush the seam; use some rust remover to stop rust internally; sand the seam and throw a couple of welds on the seam and you should be OK

Thank you!

Just be sure that you've got enough metal left so that it's still strong enough to do the job. At the very least, stab at it with an ice pick to look for thin spots.

That’s fairly common with the rust starting to spread the seam. You can use a small ball peen hammer and carefully tap the radius rod to loosen the rust. When you do that the rust will slowly fall through the spread seam. If the rod is getting thin and really full of rust and rusting through it’s time to replace the rod. Check both to be sure. They are still fairly plentiful and not real hard to get.
You can weld the spread seam shut if you want if it’s not getting paper thin.

FWIW - the seams should face down. Rust in the seam usually is from the seam facing up or the car sitting on a damp dirt floor for years.

Curious - how did you notice the seam widening, when its on the bottom. They do swell from rust or ice formation. Anyway, shake the rust out. I'd add some brand of Rust Restorer or Rust Converter or Rust Reformer (not labeled Rust Remover) into the channel. This stuff bonds with the rust & prevents further rusting. If you intend to spot weld do that first of course
This is just an example - works well

I’m replacing the rods on the ‘25 I bought because someone ran it with nuts loose and not only wore off threads but wore away half the metal. The rods I purchased online have good threads but of course they are easy to observe the seam opening.