Terrible Crunching in BB
#1
Thread Starter
Senior Member
Joined: Jun 2008
Posts: 749
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From: Northern Virginia
Bikes: Specialized Crux Elite X1, Specialized Roubaix SL4 Expert, Specialized Crux Disc
Terrible Crunching in BB
I took my 2012 Specialized Cross to the beach last week. It worked great, 250 miles in 7 days. Took it out Sunday, and at the end of the ride, I can hear creaking/crunching in the BB area.
I was thinking it was maybe sand, grit from last week, so I gave it a thorough cleaning today, cleaning the chain, cassette and front gears spotless, and re-oiled the chain and all moving joints.
Took off and did about 10 miles today and it was great, no sounds. but after that, in another 5 miles, it was horrible. It always crunches and creaks in the same pattern when the pedals are at the exact same location on the revolution.
I'm thinking the BB needs to be cleaned out and greased? Is it serviceable? The crank is listed as a FSA Omega compact BB30 ST on the spec sheet. Or do I just have to completely replace the BB if I cannot re-grease it?
I don't have the tools, the LBS will do it, just wondering what I'm looking at. Maybe it just needs tightened?
I was thinking it was maybe sand, grit from last week, so I gave it a thorough cleaning today, cleaning the chain, cassette and front gears spotless, and re-oiled the chain and all moving joints.
Took off and did about 10 miles today and it was great, no sounds. but after that, in another 5 miles, it was horrible. It always crunches and creaks in the same pattern when the pedals are at the exact same location on the revolution.
I'm thinking the BB needs to be cleaned out and greased? Is it serviceable? The crank is listed as a FSA Omega compact BB30 ST on the spec sheet. Or do I just have to completely replace the BB if I cannot re-grease it?
I don't have the tools, the LBS will do it, just wondering what I'm looking at. Maybe it just needs tightened?
__________________
Gary F.
2019 Specialized Crux Elite X1
2015 Specialized Roubaix SL4 Expert
My bike page: https://www.gwfweb.com/bicycles
Build a bike stand! https://www.gwfweb.com/bicycles/stands.html
Gary F.
2019 Specialized Crux Elite X1
2015 Specialized Roubaix SL4 Expert
My bike page: https://www.gwfweb.com/bicycles
Build a bike stand! https://www.gwfweb.com/bicycles/stands.html
#2
Senior Member


Joined: Apr 2009
Posts: 39,897
Likes: 3,865
From: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Sand is insidious. It gets everywhere, and once in, it gets comfortable and doesn't come out.
Even though you say you cleaned the chain, there may still be sand on it on glued to the chainring, but the BB isn't immune either.
I'd start by slipping the chain off the chainrings and draping it on the BB shell holding it so it doesn't touch the rings at all. Then spin the crank, and feel and listen. If there's not a hint of grinding or crunching, odds are the BB is sand free, and you can try cleaning the chain again.
Remebler there are three areas where sand can hide, the chain, the cassette an the chainrings. Sand in any one of these will be picked up and transferred to others in fairly short order, so doing one, but not all three is not going to get the job done.
Even though you say you cleaned the chain, there may still be sand on it on glued to the chainring, but the BB isn't immune either.
I'd start by slipping the chain off the chainrings and draping it on the BB shell holding it so it doesn't touch the rings at all. Then spin the crank, and feel and listen. If there's not a hint of grinding or crunching, odds are the BB is sand free, and you can try cleaning the chain again.
Remebler there are three areas where sand can hide, the chain, the cassette an the chainrings. Sand in any one of these will be picked up and transferred to others in fairly short order, so doing one, but not all three is not going to get the job done.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
#3
Senior Member
Joined: Nov 2010
Posts: 209
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From: St. Louis, MO
Bikes: 2013 Trek Madone 4.5, 2013 Trek Domane 4.3, 2009 Trek FX 7.6
Gary,
My wife and I had thoughts of taking our bikes to the beach area while we were in Michigan last week. We did but left them in the van and rented some. I won't ride my bikes around sand. All it does is destroy them.
jsjcat
My wife and I had thoughts of taking our bikes to the beach area while we were in Michigan last week. We did but left them in the van and rented some. I won't ride my bikes around sand. All it does is destroy them.
jsjcat
#4
Thread Starter
Senior Member
Joined: Jun 2008
Posts: 749
Likes: 1
From: Northern Virginia
Bikes: Specialized Crux Elite X1, Specialized Roubaix SL4 Expert, Specialized Crux Disc
It's completely quiet unless I am putting pressure on the pedals when accelerating or climbing. Just spinning it is quiet.
__________________
Gary F.
2019 Specialized Crux Elite X1
2015 Specialized Roubaix SL4 Expert
My bike page: https://www.gwfweb.com/bicycles
Build a bike stand! https://www.gwfweb.com/bicycles/stands.html
Gary F.
2019 Specialized Crux Elite X1
2015 Specialized Roubaix SL4 Expert
My bike page: https://www.gwfweb.com/bicycles
Build a bike stand! https://www.gwfweb.com/bicycles/stands.html
#5
Thread Starter
Senior Member
Joined: Jun 2008
Posts: 749
Likes: 1
From: Northern Virginia
Bikes: Specialized Crux Elite X1, Specialized Roubaix SL4 Expert, Specialized Crux Disc
Follow Up:
LBS pulled the BB and the bearings on the right side were pretty dry, and even after cleaning and greasing still did not feel smooth. They told me I could pretty still get some miles out of them, but for $40 and the fact they had it apart, I had them just put new ones in, and pack them with my favorite Mobil One grease. Took a test ride and they were quite smooth and quiet.
I got about 2200 miles out of the originals. I think last weeks 250 miles on the salt air really did them in.
LBS pulled the BB and the bearings on the right side were pretty dry, and even after cleaning and greasing still did not feel smooth. They told me I could pretty still get some miles out of them, but for $40 and the fact they had it apart, I had them just put new ones in, and pack them with my favorite Mobil One grease. Took a test ride and they were quite smooth and quiet.
I got about 2200 miles out of the originals. I think last weeks 250 miles on the salt air really did them in.
__________________
Gary F.
2019 Specialized Crux Elite X1
2015 Specialized Roubaix SL4 Expert
My bike page: https://www.gwfweb.com/bicycles
Build a bike stand! https://www.gwfweb.com/bicycles/stands.html
Gary F.
2019 Specialized Crux Elite X1
2015 Specialized Roubaix SL4 Expert
My bike page: https://www.gwfweb.com/bicycles
Build a bike stand! https://www.gwfweb.com/bicycles/stands.html
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