Sealed bearings BB
#1
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Sealed bearings BB
Hello,
I put a post on this forum before about removing one of my cottered pedal cranks. One of the cotter pins is stuck, but i've only tried the hammer method. The next step from here would be to use the vice. I don't have one of those, but I do have a drill. I'm currently tossing up the ideas of drilling it out and getting a sealed bottom bracket like this, or just riding on it as it is until it starts breaking.
My bike was made in 1987 so it's older than me. I don't think anyone has regreased the BB since it came out of the factory.
What i'd like to know is:
1). Should I drill it out, or just keep riding on it.
2). If I keep riding on it (with possibly no grease in there) will it damage the frame?
The bottom bracket is fine at the moment, but I only noticed the problem when I wanted to regrease the bottom bracket bearings.
I put a post on this forum before about removing one of my cottered pedal cranks. One of the cotter pins is stuck, but i've only tried the hammer method. The next step from here would be to use the vice. I don't have one of those, but I do have a drill. I'm currently tossing up the ideas of drilling it out and getting a sealed bottom bracket like this, or just riding on it as it is until it starts breaking.
My bike was made in 1987 so it's older than me. I don't think anyone has regreased the BB since it came out of the factory.
What i'd like to know is:
1). Should I drill it out, or just keep riding on it.
2). If I keep riding on it (with possibly no grease in there) will it damage the frame?
The bottom bracket is fine at the moment, but I only noticed the problem when I wanted to regrease the bottom bracket bearings.
#2
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You would need to get a new crankset to go with your new bottom bracket. Cottered cranks don't work with cotterless bottom brackets.
You won't damage the frame, but you will grind up your BB cups and they will continue into a downward spiral of roughness.
Drill it out and buy some new cotter pins. As long as you do BB maintenance more frequently than once every quarter century, they shouldn't be that hard to remove.
You won't damage the frame, but you will grind up your BB cups and they will continue into a downward spiral of roughness.
Drill it out and buy some new cotter pins. As long as you do BB maintenance more frequently than once every quarter century, they shouldn't be that hard to remove.
#3
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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
Also, as pointed out, there are no sealed BBs made for cottered cranks. You have the choice of replacing the BB and crankset, or (if it's OK) regreasing your BB and remounting the same cranks with a new pair of cotters.
BTW- if you hammered without properly supporting the BB, search here on BF for some of my prior posts where I describe ways to hammer out pins in a single hammer blow.
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FB
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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.
#4
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Yea. there needs tobe something solid under the crank arm .
with a hole to let the cotter pin head fall through it ..
If really at an impasse your friendly LBS is there to help. bring it by..
old guy skill, hand filing the taper on the cotter pin , so it fits
without more than a slight, tapping from a hammer to re set it..
then the nut holds it .. .. you don't pull a cotter pin into place with a wrench ..
with a hole to let the cotter pin head fall through it ..
If really at an impasse your friendly LBS is there to help. bring it by..
old guy skill, hand filing the taper on the cotter pin , so it fits
without more than a slight, tapping from a hammer to re set it..
then the nut holds it .. .. you don't pull a cotter pin into place with a wrench ..
Last edited by fietsbob; 02-13-14 at 11:08 AM.
#5
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When you say you've tried a hammer, did you properly support the crank arm, or just hammer away?
I also used lots of WD40, let it sit overnight, unturned the nut on the pin a little bit and then hit it as hard as I could.
If really at an impasse your friendly LBS is there to help. bring it by..
It's nice to know that I won't be damaging the frame. Once again (as I said in my earlier thread about this) i'll leave it and do something when it starts making noises.
#7
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Joined: Apr 2009
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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
I would be very surprised if there were any shops that didn't know about cottered cranks. OTOH- some mechanics, especially younger, less experienced mechanics may have limited or no experience removing them, and not be knowledgeable about the best practices for removing them.
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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.
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