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Old 05-05-05, 06:20 AM   #1
KevinF
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Installing Campy bottom brackets

I'm about to install a Chorus bottom bracket into an aluminum frame. There seems to be some discrepancy about whether or not to apply any lubricants to the thread:

Campagnolo's own service manual (http://www.campagnolo.com/pdf/722521...om_bracket.pdf) recommends tightening to 70Nm (apparently dry) or 30Nm with locktite.
The Park Tool web-site (http://www.parktool.com/repair_help/FAQcartdg.shtml) suggests using anti-seize for installation into an aluminum frame (which this is).

What is the recommendation of the mechanics here? It somehow seems scary to tighten something to 70Nm without any lubrication on the threads. If I lock-tite the thing in place, will it ever come out again? What's the difference between anti-seize and grease anyway?
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Old 05-05-05, 06:34 AM   #2
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the difference between anti-seize and grease is level of lubricity...anti-seize paste is less slippery and what you want for this application. Some will tell you that grease is fine and it will work as well. I would not loctite it...and would only use #242 if you had an Italian thread but you won't need it if the drive side is a reverse English thread and torqued properly to spec.
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Old 05-05-05, 06:50 AM   #3
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Quote:
Originally Posted by KevinF
I'm about to install a Chorus bottom bracket into an aluminum frame. There seems to be some discrepancy about whether or not to apply any lubricants to the thread:

Campagnolo's own service manual (http://www.campagnolo.com/pdf/722521...om_bracket.pdf) recommends tightening to 70Nm (apparently dry) or 30Nm with locktite.
The Park Tool web-site (http://www.parktool.com/repair_help/FAQcartdg.shtml) suggests using anti-seize for installation into an aluminum frame (which this is).

What is the recommendation of the mechanics here? It somehow seems scary to tighten something to 70Nm without any lubrication on the threads. If I lock-tite the thing in place, will it ever come out again? What's the difference between anti-seize and grease anyway?
Don't over anlayze it. Use grease or anti-seize(also a lube) and tighten properly. You don't even need loctite on Italian threads as the OP suggest if properly tightened.
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Old 05-05-05, 06:57 AM   #4
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Don't over anlayze it.
You will never have that problem syd...it takes basic thought.
George
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Old 05-05-05, 02:49 PM   #5
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Originally Posted by sydney
Don't over anlayze it. Use grease or anti-seize(also a lube) and tighten properly. You don't even need loctite on Italian threads as the OP suggest if properly tightened.
Actually, it's Italian threads that could benefit most from a thread-locking compound; they are far more prone to loosening, as the right side cup is not left-hand thread. So a thread locking compound could be in order. However, #242 (blue) would be the way to go. Red Loctite requires heating to something like 475 degrees to loosen, which would fry paint and melt powder coating.
But, that being said, grease almost always is the preferred material, as it's good at displacing water and preventing rust in a very vulnerable spot. The key is proper torque on the cup to keep it in place!
While you've got the BB apart, have the threads chased and the shell edges faced to insure the best fit and long bearing life.
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Old 05-05-05, 03:04 PM   #6
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Originally Posted by LV2TNDM
Actually, it's Italian threads that could benefit most from a thread-locking compound; they are far more prone to loosening, as the right side cup is not left-hand thread. So a thread locking compound could be in order. However, #242 (blue) would be the way to go. Red Loctite requires heating to something like 475 degrees to loosen, which would fry paint and melt powder coating.
But, that being said, grease almost always is the preferred material, as it's good at displacing water and preventing rust in a very vulnerable spot. The key is proper torque on the cup to keep it in place!
correctomento ! I currently have 10 Italian threaded rides in use and not a one of them has loctite and no self loosening. Had the issue once a long time ago , then I learned to properly tighten them.
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Old 05-05-05, 08:20 PM   #7
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Thanks for all the advice. My BB is English-threaded, so I'm going to stay away from the lock-tite. I'll find some anti-seize and start torqueing. Thanks for the advice
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