Would you be concerned about the condition of this «swingarm» ?

[increasing]

I’ve been riding my -99 Honda ST1100 Pan European ABSII this summer and am very pleased with the bike. The luggage options are excellent, too … it has two genuine side cases with inner bags, plus fold-out cargo hooks on both the left and right sides of the seat. These can be used with a cargo net or, for instance, a 60-liter dry bag

A potential buyer has recently shown interest, but he is a bit concerned about rust on the rear swingarm.

After riding this summer, I wiped the swingarm down with a damp cloth before taking the photos. What I see is a 27-year-old swingarm that has never been ridden on salted winter roads and - has never been refurbished or repainted. In my assessment, it appears to be in good condition considering its age.

I am attaching seven photos and would appreciate your opinion: Would you be concerned about the condition of this swingarm based on what you see in the pictures?

 

[Uncle Phil]

See if you can poke any holes in it.

 

[MattSTlouis]

Looks good to me. His wife probably said no and he did not want to sound like a pansy with the real story.

 

[increasing]

Thanks

I’ve tapped the underside with a ball-peen hammer, and the sound is solid and firm everywhere. I also tapped around with a thin, pointed screwdriver in a few spots I was unsure about, but found nothing. The drain holes I can see and locate are clear.

But is there anything in the photos that you think I should be worried about?

 

[Uncle Phil]

Nope - go ride!
I have about 5 of those in Uncle Phil's Parts Warehouse.
They seldom go bad on this side of the pond.

 

[Sunday Rider]

This wouldn't stop me from buying it. The last picture is the worst of the bunch and it looks good to me. I've seen more rust than that on bikes that are still ridden.

 

[increasing]

Thank you very much for your time and for the positive feedback that supports my earlier assessments However, it certainly wouldn't hurt to apply a penetrating rust preventative to the inside of the swingarm and perhaps brush some onto the front section, which is exposed to stone chips.

 

[SMSW]

Looks like surface rust to me. Next time you change the rear tire, consider hitting visible rust with one of those rust converters - locktite makes one (don't know if it is available on your side of the pond). Or touch up the rust w/ a sealing paint after a bit of wire brushing.

 

[increasing]

A very good idea … for the next tire change

 

[jdmccright]

It's absolutely fine. He's just trying to get you to come down in price bc he knows it's an issue with some bikes. If he keeps whining about it then tell him to go kick rocks and ride away happy.

 

[jfheath]

That looks pretty well perfect to me.

This was mine when I discovered patches that were much worse than yours. Rust on many of the seams and exposed areas - bubbling up underneath the paint. I took it off - a lot of the paint came off with a wallpaper scrapper - it wasn't attached to anything and had separated from the metal.
This photo was taken half way through the cleaning up - getting rid of the rust - process. It looks like I was halfway through the job. The light rust on the inside of the arms - where the wheel would go - looks like an overnight dusting having cleaned it up and left it in the gargage overnight.

So I still have a fair bit of cleaning up, and some kill-rust compound - before painting it up again with Hammerite paint. It looked worse than yours, but there was no serious corosion. Taken 2008 just before I sold it. 70,009 miles on the clock. Riding about 12,000 miles per year in all weathers including salted UK winter roads. You can see that it seems to have affected the welded joints more than anywhere else - which is what yours seems to be showing.

Removing the swinging arm was no big deal. Getting the final drive off was a bit awkward, and removing the wires, cables and hoses and leaving them safely supported. But you must have the correct tool for tightening the swinging arm bearing bolt.
I'm not suggesting that you need to do that - I'd be tempted to rub let some warm ACF50 soak into the bits that are showing rust to protect it from spreading and get a few more seasons from it. Just keep an eye on it.


And after - difficult to get in to paint those braces at the top end of the photo below. It could have done with a bath of paint really.

 

[ST Gui]

A potential buyer has recently shown interest, but he is a bit concerned about rust on the rear swingarm.

Someone not particularly knowledgeable about degrees of rust and has heard that rust never sleeps should be concerned. Then when schooled on what's what they can be relieved or move on. Only you are in a position to judge his motives. As everyone has said your rust-case is NBD. Clean it up and repaint is what I'd do.

They seldom go bad on this side of the pond.

I've just watched a couple of episodes of Cars SOS. It's one of those rehab a barn find in a time constraint (ain't it always) shows. I don't know the provenance of the guys presenting and doing the work. These aren't restorations but the results are pretty good.

The rust! The rust! The car in each episode was 30 and 40yrs shed-stored. You could have demoed both of them with that ball-peen hammer. In some places your pinkie finger would have worked. It was real work putting pack to eye-candy shape. increasing's swing arm is pristine in comparison.

 

[Uncle Phil]

The rust! The rust! The car in each episode was 30 and 40yrs shed-stored. You could have demoed both of them with that ball-peen hammer. In some places your pinkie finger would have worked. It was real work putting pack to eye-candy shape. increasing's swing arm is pristine in comparison.

It just depends on how the ST1100 was cared for and where and when it was ridden.
I have a 'few' ST1100s and the swingarms are solid back to a 1991 model.
I also have 4 or 5 extra swingarms that are solid in Uncle Phil's Parts Department.
The UK uses some sort of winter stuff on the highways that really eats into the swingarms over there.
I don't know if Norway does or not.

 

[increasing]

Do not compare a motorcycle that has never been ridden in winter conditions with cars driven year-round on salted roads.

I have spoken to the first two owners, as well as the third owner (based in the central eastern region of Norway who bought the bike in the autumn of 2003), and none of them used the bike in winter.

Few people in Norway ride motorcycles in winter, there are some exceptions, of course but I do not ride in winter either. I have been the fourth owner since the spring of 2025.