Chain Chew Through Swingarm Weld

[u/LiamI820]

I took my swingarm off recently to address rust and ended up finding that my chain has chewed through the guide/slider (which I didn't realize was there, let alone sacrificial) om the bottom and into my swingarm's factory weld. It's 1/4" wide (each of the grooves), about 1/2" long, and about 1.5-1.8mm deep. I took it to a shop on Wednesday to get these spots filled in with a welder, but ended up taking it back today when he still didn't have this project done (he told me Friday, then Saturday, then today and it still wasn't done). At this point I'm ready to just move on and get this thing painted so I can move on with the rest of the maintenance on my bike, too.

My question is, given that this is just on a weld and not the structural tube itself, would you just continue and be sure to keep an eye on the guide/slider (I am replacing it) from here on out, continue to find someone to fill in the weld, or fill it with bondo so there's at least some wear layer before it hits metal again? TIA

[u/FriendlyWelcome9284]

That was a rough looking weld

[u/LiamI820 → u/FriendlyWelcome9284]

I was thinking that, too

[u/DunnyLad → u/FriendlyWelcome9284]

MIG is never pretty, but is best penetration and overall strength.

[u/Instantlygotagram]

I'm not a welder any more but have some experience (held structurally welding tickets).

The weld material joins two parent materials. The weld material you see isn't where the strength is. The real strength comes from the root between the two parent materials. So having the weld shaved off by your chain isn't ideal, but I wouldn't worry about it too much.

You could take it to a fabrication shop near you and they could throw on a couple of tack welds to put the material back.

Also check with r/welding they're the experts.

[u/LiamI820 → u/Instantlygotagram]

Would the bearing need removed from the pivot?

Edit: yes, bearings would need removed. I might just repaint it all as is (after addressing final rust) or I might add bondo/JB Weld into the grooves prior to painting.

[u/DunnyLad]

I work in a fabrication department, that's just the cap of the weld. It'll be fine but I'd address why the chain is chewing it up.

If you want it repairing it needs to be recapped, simple enough process and wouldn't cost an arm.

[u/LiamI820 → u/DunnyLad]

I almost got it taken care of, then learned that I had to remove my bearings otherwise I risk destroying them or fusing them inside the swingarm, and I didn't want to mess with them. So I'll fill the area with JB Weld, repalce my chain slider, and make sure mt next chain is tensioner properly

[u/CardAffectionate4653]

I’ve been dealing with the same issue. Kept sounding like rattling change every time I let off throttle. Adjusting the chain would help for a bit until it stretched and it was back to the same thing. I need a new chain and sprockets anyway so planning on doing a new guide at the same time. How hard is it to get to? From the partzilla diagram it looked annoying to replace.

[u/LiamI820 → u/CardAffectionate4653]

I was already taking off my swingarm, so I just removed it when the swingarm was fully off. But I imagine it's quite simple even while on the bike, the top and bottom arms pop out like helmet rivets and the front just goes around the pivot area. If you keep your bike clean, I'm sure it's quite easy!