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Discussion Starter · #1 ·
So I'm finishing up the remote lockout install on my new Duke race last night, and I decide to unscrew brake bosses because I'm running discs on this bike. I go to wrench on them and they are in there tight! I pop the first one out and low and behold, it is rusted. I mean deeply rusted, in the threads. On a new fork! I unscrewed the other one and it was the same story. No grease on them either.

Now I know that when you mix alloys, all the oxidizing that occurs throughout the body of the metal happens to the most oxygen-accepting metal first. This is why they keep blocks of zinc in the bottom of aircraft carriers - the zinc rusts and the carrier doesn't. But holy crap, this thing is NEW and the brake bosses are nearly rusted into the fork?

Anyone else pulled these and know if it's structurally safe to remove them? I'm going to try to find their thread pattern and order some nylon replacements, anyone else done this?

Funny mildly related story: the mechanic doing the install on my old Marzocchi X-fly was kind enough to pull the brake bosses out of it for me when the bike was built. When he pointed this out, I showed him the little orange sticker on the back that says "caution removing brake bosses may result in permanent injury or death". Turns out Marz used the brake bosses to bond the arch to the stanchions, removing it meant you hit your first log and your fork blows to pieces and you get to play Superman.

So this time I'm doing myself. Haven't gotten to ride this RS yet but so far not confidence inspiring. Maybe I should leave the steel brake bosses in so my fork won't rust?
 

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I pulled the bosses from my RS Pilot XC a year ago and have had no problems. Mine weren't rusted in like yours but still a pain to remove.

I am not sure what the corrosion factor of Magnesium is but i couldn't imagine that it is any worse than the steel bolts you removed.
 

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Gambrills said:
So I'm finishing up the remote lockout install on my new Duke race last night, and I decide to unscrew brake bosses because I'm running discs on this bike. I go to wrench on them and they are in there tight! I pop the first one out and low and behold, it is rusted. I mean deeply rusted, in the threads. On a new fork! I unscrewed the other one and it was the same story. No grease on them either.

Now I know that when you mix alloys, all the oxidizing that occurs throughout the body of the metal happens to the most oxygen-accepting metal first. This is why they keep blocks of zinc in the bottom of aircraft carriers - the zinc rusts and the carrier doesn't. But holy crap, this thing is NEW and the brake bosses are nearly rusted into the fork?

Anyone else pulled these and know if it's structurally safe to remove them? I'm going to try to find their thread pattern and order some nylon replacements, anyone else done this?

Funny mildly related story: the mechanic doing the install on my old Marzocchi X-fly was kind enough to pull the brake bosses out of it for me when the bike was built. When he pointed this out, I showed him the little orange sticker on the back that says "caution removing brake bosses may result in permanent injury or death". Turns out Marz used the brake bosses to bond the arch to the stanchions, removing it meant you hit your first log and your fork blows to pieces and you get to play Superman.

So this time I'm doing myself. Haven't gotten to ride this RS yet but so far not confidence inspiring. Maybe I should leave the steel brake bosses in so my fork won't rust?
Are you sure it was rust, and not just a rust colored thread locking compound? That is what was on the bosses that I took out of my 04 Duke SL U-turn, that's why it's hard to unscrew them. I took them out when the fork was new, and I've been running that fork since last fall with no problems. Problem Solvers makes plugs for the brake bosses http://www.bikemannetwork.com/Merch...uct_Code=FK9940&Category_Code=COMPBRKDPRTPLUG
 

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Kind of OT, but my rear bosses on my fsr are stuck in pretty tight. I think it has something to do with the paint. It looks like the bosses were installed before the bike was painted. I destroyed one trying to remove it (actually my LBS did. At least they asked before they did it...). Anyone have an idea how to get them out? Sorry, I dont really like to hijack the thread like this. Just thought it was somewhat relevent. As for rust, when I removed my bosses from my fox, not a sign at all. Maybe it was some bonding agent like a previous poster said.
 

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Discussion Starter · #5 ·
doh!

VT Mike said:
Are you sure it was rust, and not just a rust colored thread locking compound? That is what was on the bosses that I took out of my 04 Duke SL U-turn, that's why it's hard to unscrew them. I took them out when the fork was new, and I've been running that fork since last fall with no problems. Problem Solvers makes plugs for the brake bosses http://www.bikemannetwork.com/Merch...uct_Code=FK9940&Category_Code=COMPBRKDPRTPLUG
Wow, you could be right! I will have to scrape off a sample of it and see if it is magnetic. Thanks!
 
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