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Bottom Bracket Blown
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I have a SRAM Force BB. I’ve noticed lot of creaking and awful noise especially up climbs and when torque is forcefully applied to the crank arms. I had no
idea. LBS said I might have corrosion in the frame. A riding buddy suggested I replace the BB.

How big a difference will a new BB make as in how many watts have I been losing? 5-10? As well, should I go with a $30 GXP or something better with ceramic bearings? Is there that big of a deal? I also heard the ones with ceramic bearings wear out in 6-12 months. Is that true?
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Re: Bottom Bracket Blown [mwanner13] [ In reply to ]
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I go through 2-3 BB bearing sets a year. They are definitely a wear item. Just a mid range bearing is fine. BB infinite is very nice, but I'd keep it race only.
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Re: Bottom Bracket Blown [iamuwere] [ In reply to ]
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Thanks for the feedback. It sounds like I need a base level BB and replace it more often.
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Re: Bottom Bracket Blown [mwanner13] [ In reply to ]
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Worn pedal bearings can also mimic BB creaking/popping. Remove your cranks and inspect the BB for any corrosion or a crunchy feel as you rotate the bearing with your fingers. If the BB feels/looks fine, I'd focus on the pedals.

DM
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Re: Bottom Bracket Blown [iamuwere] [ In reply to ]
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iamuwere wrote:
I go through 2-3 BB bearing sets a year. They are definitely a wear item. Just a mid range bearing is fine. BB infinite is very nice, but I'd keep it race only.

Maybe one BB every 3 years. I weigh 145lbs and my FTP is only 175. Is that why I don't?

How much force would it take to go through 2-3 a year? Is this regardless of which bike/BB you're on?

Indoor Triathlete - I thought I was right, until I realized I was wrong.
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Re: Bottom Bracket Blown [IT] [ In reply to ]
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I’m 200-205 pounds. Ftp 340-360 depending on the cycle
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Re: Bottom Bracket Blown [mwanner13] [ In reply to ]
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Just replace the bottom bracket it's not a big deal and in some climates we do it a lot. The ceramic bearings are not longer-lasting I would just use a regular OEM bearing. If you don't own the tools, consider getting the wrench and the little thing to preload the crank arm, it's inexpensive. Remember the right side threads on the wrong way, clean up the threads and be a little careful and torque the pinch bolts down tight enough.

I use Shimano cranks on most of my bikes because I got sick of replacing shot GXP's on the off road bikes. Shimano isn't perfect, but it's better.
Last edited by: jroden: Jun 30, 19 16:23
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Re: Bottom Bracket Blown [jroden] [ In reply to ]
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if you wanted to spend more and get a better replacement, this is a tried and true option

https://www.retro-gression.com/...g-gxp-bottom-bracket
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Re: Bottom Bracket Blown [djmercer] [ In reply to ]
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djmercer wrote:
Worn pedal bearings can also mimic BB creaking/popping. Remove your cranks and inspect the BB for any corrosion or a crunchy feel as you rotate the bearing with your fingers. If the BB feels/looks fine, I'd focus on the pedals.

DM
This .^.
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Re: Bottom Bracket Blown [mwanner13] [ In reply to ]
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Off-road BBs can wear very quickly. But it can take forever to wear a road BB. I have one 12 year old GXP BB on a road bike with at least 30k miles and it still spins smooth. Been ridden in some lousy conditions and grease changed about every 5k miles.
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Re: Bottom Bracket Blown [carlosflanders] [ In reply to ]
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How do you re grease that thing? Do you just leave the bottom bracket in place on the bike and pump grease in?
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