Welding a GT rear swing arm pivot area RTS 3

[Dface]

I am actually asking for a friend as they say. What’s the likelihood of this being repaired successfully?

 

[bikeworkshop]

Zero
It's broken due to stress
A new weld will be weaker, and there's not much space to build up.

It might be usable as a showpiece or gently cruising around.

A better repair would be to fabricate a new forked end on a sleeve (out of steel) that could then be slipped over and glued onto the old stay. Your new pivot piece could be strong enough, and a modern glue should carry the bond.

Better still, replace the part!

 

[Dface]

He’s just bought it used today and was all gunked up He’ll definitely not be off-roading on it but wants to ride it on road for pleasure. What’s the chances of someone who repairs car alloys sorting it? Are we talking different materials or could it be a fix that’s not pretty but safe. Thanks for your time.

 

[bikeworkshop]

It won't have adequate strength.
The original piece will have been heat treated, but a new weld will be all over the place.
It will break quickly, my guess would be first pedal stroke.

Replace the part.

 

[fettler]

Machine a new lug and cut/weld the whole end on, be better or search for a spare arm.

 

[Dface]

I will pass on your advice. Thanks for the answers.

 

[ishaw]

It has certainly been done before. What I've seen, and as suggested above is the cracked part is completely removed and a new one welded on.

Alternatively a new (well used) chain stay assembly, or even a whole rear end. I have a spare steel rear end in my stash for this reason, and a few alloy ones.

 

[dyna-ti]

Zero
It's broken due to stress
A new weld will be weaker, and there's not much space to build up.

Im sure it could be welded then ground back, maybe the hole rebored.
It's just a case of do you have an oven big enough to anneal it in.

 

[d8mok]

Before doing anything I’d check the rest of the main frame too as it could also be cracked.

I wouldn’t bother trying to weld and heat treat the rest triangle when a rear end would cost very little or even a full bike.

I had a RTS3 in 1995 lovingly named “Really Toss Suspension” as for the tiny amount of travel it wasn’t worth the constant bushing
Replacement and rear ends

 

[ishaw]

Before doing anything I’d check the rest of the main frame too as it could also be cracked.

I wouldn’t bother trying to weld and heat treat the rest triangle when a rear end would cost very little or even a full bike.

I had a RTS3 in 1995 lovingly named “Really Toss Suspension” as for the tiny amount of travel it wasn’t worth the constant bushing
Replacement and rear ends

Don't listen, they are really nice bikes. The only real challenge is the proprietary shock sizing and alternatives should you need one.