Underside of fenders?

For those wanting to keep their bike the way the factory made them.

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Olafskii
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Underside of fenders?

Post by Olafskii »

Does anybody have recommendations for restoring the underside of fenders? When new these were probably were never chromed very well and might have even rusted when the bike was new. I could leave as is, or glass bead blast or even get it re-chromed. The latter option doesn't make sense because nobody will see under the fender (this bike will be a rider, not a concourse queen). Leaving as isn't ideal--the rusting will continue. And, glass bead blasting, while removing rust, would simply invite more rust. Has anyone ever painted the underside of fenders? Perhaps using a grey zinc primer? (of course I'd remove all the removable bits and properly mask everything to prevent spray on the chrome top. Thoughts?

O
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Alan H
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Re: Underside of fenders?

Post by Alan H »

Wire brush or bead/media blast and paint with hammerite silver. No-one is any the wiser and it doesn't re-rust.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
Zunspec4
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Re: Underside of fenders?

Post by Zunspec4 »

+1 with the Hammerite Silver.
dgoodsy
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Re: Underside of fenders?

Post by dgoodsy »

I briefly googled the hammerite product, lots of good reviews on it in similar applications. Since you say its a rider and no one will see the underside of it I think POR15 would be a good option as well. Lots of people use it on car subframes so I can't imagine it wouldn't be up to the task here.
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joolstacho
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Re: Underside of fenders?

Post by joolstacho »

Thoroughly clean and degrease, roughen up the surface, neutralise with rust converter, then paint with automotive underseal. It's thick and it will not chip with road gravel etc like 'normal' paint.
Bloop2
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Re: Underside of fenders?

Post by Bloop2 »

I just use a silver rust inhibiting paint, I don't mask anything off, the over spray can be removed with acetone.
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Olafskii
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Re: Underside of fenders?

Post by Olafskii »

Thanks for all the tips. I've decided to go with the POR15 product--Silver. In part because i was able to purchase the degreaser and etching cleaner right here in town at Canadian Tire and Lordco Auto parts. I ordered the pint of silver direct from POR15-Canada. Shipping cost was $15 which isn't too bad.

Merry Christmas everyone.

O
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joethebike
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Re: Underside of fenders?

Post by joethebike »

My tip is to carefully examine the strengthening gusset spot welded to the underside as these have a hollow section which collects dirt, keeping a wet surface constantly against the metal and out of sight. Two of my mudguards have rusted badly under these gussets with the corrosion breaking through to the chromed top surface.
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Alan H
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Re: Underside of fenders?

Post by Alan H »

Nothing worse than a rusty gusset. I would think it's hell on the undercarriage.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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