Swingarm damage repair

[TeriyakiBlaster]

I had a brilliant ride last weekend, roughly 700km of gravel and twisty roads. About an hour down a logging road and nearing our campsite for the night, we stopped to admire some scenery when I dropped the bike on the right side for the first time. Ironically, I was only moving it to prevent a nearby KTM 1190 from tipping over into it on the soft uneven dirt. In any case, we picked it up and gave it a once over and there didn’t appear to be any damage at all so we were on our way.
 

Unfortunately, I didn’t realize that the muffler had bent in slightly, enough to contact swingarm. I had previously seen another thread about this where one member described the exhaust hanger as being made of cheese, and mine was certainly no exception. I really should have paid more attention to it. It wasn’t until I got the bike home and was giving it a wash that I discovered this damage. So after sulking about it for a few days I decided I should clean up the damage.

 

 

If this happens to your bike, you need to assess your damage and weigh the risk of repair vs. swingarm replacement for yourself - or seek a professional opinion before going ahead. Though I am an aircraft structures tech by trade, I don’t claim to be an absolute expert on this kind of thing and would advise you to proceed with caution. The swingarm is hollow and of minimal wall thickness, and this repair will do effectively nothing to restore the original strength - only for aesthetic and corrosion prevention purposes.

 

In any case, I measured the damage to be about 0.008” deep and a fairly smooth contour with no signs of cracking or anything of that nature. You want a metal epoxy that will bond with the aluminum and fill in the damaged/missing material, and allow you to sand and re-paint the area once it’s cured. I chose JB Weld KwikWeld as it sets in 6 minutes and cures in 4 hours. There are several products that will work, but for obvious reasons I didn’t want to leave the bike in this position for too long so that’s the one I chose.

 

 

 

To be continued...

[TeriyakiBlaster]

Once you’ve got the exhaust removed, you need to clean the damaged area and remove paint around the repair. I used a wire brush and thoroughly cleaned the entire side of the swingarm with brake cleaner. You want to leave the damaged area fairly rough so the adhesive has something to bite into, while removing as little of the original material as possible. Sharp edges or deep gouges would need to be smoothed out for sure, though. 
 

From there it’s as simple as mixing both components at a 1:1 ratio and filling in the damage. You have to work quickly before the epoxy starts setting up, don’t worry about getting a perfectly smooth finish as you will be sanding it flat later. Better to overfill than underfill to prevent leaving a void.

 

 

Edited June 27, 2020 by TeriyakiBlaster

[TeriyakiBlaster]

After that, you need to wait for the epoxy to completely cure and sand it flat. I used a rubber block with 320 grit sandpaper and went at it from a few different angles until it was completely smooth and flush with the surrounding surface. The flat on the swingarm helps with this, you just have to keep the block as level as possible and apply even pressure until you can’t feel any raised edges with your hand.

 

 

Finally, you need to clean the area thoroughly once again with brake cleaner and mask off anything you want to avoid getting overspray on. Clean it once again for good measure and fade in 3 light coats of quality black spray paint. I prefer to not tape off hard edges when using touch up paint, it’s best to overlap by a few inches all around so that the transition isn’t quite so noticeable. The swingarm is something between flat and semi-gloss in a somewhat textured finish. I used semi-gloss and, in hindsight, flat may have been closer. It won’t matter as soon as I get it back off road and dirty again, or I can spray it with something different later if it bothers me.
 

[TeriyakiBlaster]

That’s pretty much it! The end result isn’t perfect but it was also ~ $15 and not whatever a new swingarm would have cost me. Remember to straighten out your exhaust before or after re-installing it (I chose to brace against the tire with my foot and pull it out, so that everything would be straightened in the same rate that it was bent, if that makes sense) while I await my HP Corse slip-on.
 

 

I hope this helps somebody with the same problem. Again, it’s not an ideal fix for every type of damage - but for the majority of cases you can be assured that it’s not always the end of the world or terribly expensive to rectify. In my research it seems that welding would be ill-advised as it would negatively affect the heat treatment of the swingarm so there aren’t many better options. Once you’ve done this be sure to keep a close eye on it for a while to monitor for cracking etc., and eventually you can forget that it ever happened.

 

Cheers!

Edited June 27, 2020 by TeriyakiBlaster

[Louis]

Nice repair, I hate scrape marks. This is why I won't buy an expensive aftermarket exhaust, that would have needed repairs too. Unless you've got  a high up one  like a Huzar exhaust. I'm waiting till more options become available. 

[Rider 101]

I dropped mine on the RHS and put a mark on the exhaust. I had a good look at the exhaust bracket for any bending. I don't think it is but a line of sight looks as if the muffler runs close to the swingarm when the suspension is compressed.

[Vtamb81]

5 hours ago, Louis said:

Nice repair, I hate scrape marks. This is why I won't buy an expensive aftermarket exhaust, that would have needed repairs too. Unless you've got  a high up one  like a Huzar exhaust. I'm waiting till more options become available. 

Agree. I’m waiting for someone to come out with a high exhaust solution (Like CamelADV)....pretty big design flaw IMO. I’m not a fan of the Huzar look or pipe design. 

[bth2]

maybe ,as a stop gap, some sort of protection afixed to the swingarm. when the can does crush on to the arm it doesnt damage it.

 

[Stevoh]

Nice job TeriyakiBlaster, I work in a Body shop, perfect repair to my eye!

[Hammerhead]

Dropped mine on the pipe yesterday too. Definitely bent in, but thanks to the prior warnings I pulled it back out before this happened. Few pipe scratches were the worst of it. Thanks for the heads up !

[albacore]

Is the exhaust bracket welded or bolted to the frame?

[rumrum]

Guess it is better the exhaust bracket bends rather than the sub frame and write the bike off.

[Toei]

21 minutes ago, rumrum said:

Guess it is better the exhaust bracket bends rather than the sub frame and write the bike off.

Well do it enough times and the bracket is going to crack/break, which will write the bike off at that point.  Assuming the bracket is welded on which it appears to be.  

[albacore]

12 minutes ago, rumrum said:

Guess it is better the exhaust bracket bends rather than the sub frame and write the bike off.

It's not something that's holding me back from a purchase and I fully assume I'll be dropping the bike but I'd much rather the bracket be bolted to the subframe rather than welded. Bending that hanger back and forth a few times and it's a possible insurance claim anyway.

[albacore]

Looks like Toei beat me to it by a minute.

[Toei]

On 6/26/2020 at 9:20 PM, TeriyakiBlaster said:

I had previously seen another thread about this where one member described the exhaust hanger as being made of cheese, and mine was certainly no exception.
 

 

To clarify this statement:  Are you referring to the exhaust hanger welded to the frame, or the bracket attached to the exhaust can that bolts to the frame hanger?  Which one bent?

Edited July 1, 2020 by Toei

[TeriyakiBlaster]

On 6/30/2020 at 5:21 PM, Toei said:

To clarify this statement:  Are you referring to the exhaust hanger welded to the frame, or the bracket attached to the exhaust can that bolts to the frame hanger?  Which one bent?

It’s mostly the exhaust hanger on the muffler itself that bends. As mentioned, the actual bracket is welded to the frame and it’s definitely a bigger deal if you manage to damage that. The key is to check it over immediately if you ever drop the bike on that side.

[Adrenolin]

Swingarm guards or just heat and mold some Kydex around it and affix with zip ties. I called out the exhaust a year or so ago wishing both for a higher option and a more durable setup as well. WTH was Yamaha thinking with this. Seem over a dozen post over the last year with damage like this.

[Totti]

I just put some Gorilla -tape to the swing arm and to the mud guard.

[iKeoxD]

Anyone with a 3d printer able to make a plastic guard I'll buy one? 

Edited November 1, 2020 by iKeoxD

[NeverMetThePope]

Fixed!