Cracked Swingarm

My '08 swingarm has a definite fracture in the lower weld on the left side. Just like this guy's '06 in his thread: http://www.thumpertalk.com/forum/showthread.php?t=600817&highlight=swingarm+crack (go to post #9 for his pics)

Money is kinda tight after the engine rebuid, so buying a new $500 swingarm is not an option. Would a good welder be able to fix this for a reasonable price? or should I buy a used $100 swingarm off ebay?

If you can pick up a good used one I'd go that route.

If you can pick up a good used one I'd go that route.

Yeah, that is what I originally thought. I called an Aluminum Fab shop in town and he said he does it all the time for guys. $35-$70 bucks same day done... So now I'm leaning more towards just a quick fix.

a quick fix is the right way round

The only problem with used swingarms is its hard to tell if the slider where the brake caliper slides onto is worn out.

There is no reason an experienced welder couldn't return this to it's original strength/reliability/quality if it's a fractured weld. I don't see it as a quick fix but a cheaper alternative to a new one. Just keep an eye on it for a while after repair.

Aluminum loses a lot of strength if welded repeatedly. If it cracks again consider replacing it.

aluminum weld by a real welder will last as much

I just got it welded by a custom fab shop for $40. He guarentees his work. Suprisingly, he has a lot of bikes come in for the same reason and has never seen a repeat failure(at least on his welds).

my buddy owns a fabrication shop and says aluminium need to be heat treated after its welded or it will just break

my buddy owns a fabrication shop and says aluminium need to be heat treated after its welded or it will just break

like baked in an oven?

The welder I took it to has had a fab shop here in town about 20yrs. He didn't say anything about heat treatment. He told me it would never crack agian, especially with the end tubing extending inside the larger part of the swingarm a couple of inchs.

I've had 2 Yamaha swingarms welded and both bikes are still out there running.

I wouldn't worry about it.

It will be stronger if heat treated, yes, but it isn't any different than a typical casting if it's not. I've never had a problem with a well done weld.

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