Springer fork internal rust

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whenpancomestoshovel
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Springer fork internal rust

#1

Post by whenpancomestoshovel » Sat Jul 22, 2017 6:46 am

I bought a springer fork a year ago which was badly painted I used biological paint stripper and brushed it with water afterwards, then painted it black.

I was somewhat surprised by the venting/draining of the forks when I was working on the legs back then, and it kind of got me thinking the other day.
What if water (or worse even paint stripper) got inside the legs?
I see only two holes small holes on the front legs, but I assume these are to prevent pressure build up during brazing
Image

On rear legs/main legs there is only the holes a the top clamp, and the brake cable hole at the left leg.
Image

Am I worrying for rust for no reason? I believe I blew some compressed air inside these holes at the time, but I have to assume I was pretty rough with water when stripping the paint.

Are the OEM holes really enough to let water/steam escape?



RUBONE
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Re: Springer fork internal rust

#2

Post by RUBONE » Sat Jul 22, 2017 2:41 pm

All springers have a certain amount of rust in them, the tops of the legs are open and the legs are hollow so some moisture infiltration is inevitable. Often on older forks they have filled, frozen , and split. None of it is a huge worry (unless you are the worrying type in which case this might not be the best hobby), and running the top plate and keeping the weep holes open is sufficient to keep the rust at bay.

whenpancomestoshovel
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Re: Springer fork internal rust

#3

Post by whenpancomestoshovel » Sat Jul 22, 2017 2:50 pm

RUBONE wrote:
Sat Jul 22, 2017 2:41 pm
All springers have a certain amount of rust in them, the tops of the legs are open and the legs are hollow so some moisture infiltration is inevitable. Often on older forks they have filled, frozen , and split. None of it is a huge worry (unless you are the worrying type in which case this might not be the best hobby), and running the top plate and keeping the weep holes open is sufficient to keep the rust at bay.
Thanks for the response. I'll probably just spray some WD 40 down the tubes :)

whenpancomestoshovel
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Re: Springer fork internal rust

#4

Post by whenpancomestoshovel » Sun Jul 23, 2017 7:57 am

When I had the paint off i recall there were some points where the brazing didn't create a complete joint between the parts. Through these points water/air could enter during my paint removal process

Image

Now that the fork is painted these holes are sealed. Are there any other points where this space can vent through? Is there a hole through the steering stem bottom where water/air can escape (see picture below)?

Image

I am considering putting a drill to it to avoid the possiblity of them being destroyed from the inside. This is not something I am happy to do.

1950Panhead
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Re: Springer fork internal rust

#5

Post by 1950Panhead » Sun Jul 23, 2017 4:33 pm

I am considering putting a drill to it to avoid the possiblity of them being destroyed from the inside. This is not something I am happy to do.
You don't have to do any of this, fill the tubes with oil if it makes you happy.

whenpancomestoshovel
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Re: Springer fork internal rust

#6

Post by whenpancomestoshovel » Sun Jul 23, 2017 8:31 pm

1950Panhead wrote:
Sun Jul 23, 2017 4:33 pm
I am considering putting a drill to it to avoid the possiblity of them being destroyed from the inside. This is not something I am happy to do.
You don't have to do any of this, fill the tubes with oil if it makes you happy.
I just figured it as a precaution in case water is entrapped in fork lowers as seen in the last picture. Is there an internal venting I am missing?
From my understanding of the chemics, water is merely a catalyst for creating rust, meaning it can basically go on forever if oxygen is available.

From my understanding the forks are furnance brazed. Wouldn't this process require some kind of venting for the fork lowers for the pressure build up?

RUBONE
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Re: Springer fork internal rust

#7

Post by RUBONE » Sun Jul 23, 2017 9:17 pm

As I posted in my first response, the legs are hollow and open to the atmosphere. No pressure buildup is possible...The lowers are not a separate piece, the legs are one piece.

whenpancomestoshovel
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Re: Springer fork internal rust

#8

Post by whenpancomestoshovel » Mon Jul 24, 2017 5:44 am

I realize the legs are one piece. My concern is the fork perch, from which the stem protrudes. It seems to me this is a separate space, unless I am missing something.

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