The part of your bike that contains the axis the cranks arms spin 'round. (The crank arms are where the pedals attach.)

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18
votes
12answers
24k views

Creaking from cranks/spindle. How to fix?

Recently the cranks on my bike started to creak. I checked with my usual "bike-bible" Park Tool. They recommended dis-assemble, lubricate, re-assemble. So I did that. Remove cranks. Remove spindle. ...
12
votes
5answers
9k views

How often should I grease and repack my hubs and bottom bracket?

I am commuting 7 miles a day (round trip) in all weather in New England (temperate, moderately wet climate, cold winters). Overall I am putting about 1000 miles per year on my commuter bike, a 2009 ...
12
votes
3answers
3k views

How do I know when to replace my bottom bracket?

With out completely removing the cranks and bottom bracket, how can I tell when it's time to replace my bottom bracket? The current symptom is a slightly 'rough' feeling when I pedal. It's not ...
10
votes
2answers
4k views

What are the benefits of external bottom brackets?

Pretty soon, I plan to replace the bottom bracket on my early 90's Sakae Litage road bike. It takes a standard, English-threaded bottom bracket. Right now I think it contains loose bearings--I was ...
8
votes
7answers
8k views

How to remove a crank arm with stripped threads?

A friend called me up yesterday after a mis-adventure during his attempt at a bottom bracket overhaul. He stripped out the threads on the (left) crank arm while using a Park crank puller. In a pinch, ...
7
votes
4answers
199 views

Help needed identifying mystery screws on 1940s tandem

My tandem has two small screws above each bottom bracket, one on each side (so four in total). I've not seen them on any other bike, and I can't figure out what they're for! Suggestions so far have ...
7
votes
3answers
1k views

How do I stop my EBB (Eccentric Bottom Bracket) from creaking?

I have a '09 Felt Niner 29" SS with an EBB. After a thorough clean and reassembly of the BB the creaking will subside for a ride or so and then come back. Any suggestions? EDIT: the problem appears ...
7
votes
3answers
4k views

Annoying clicking sound from the bottom bracket

I just purchased a Fuji ACR 2.0 road bike from a guy who bought it three months back but didn't ride it at all. I brought it home and found that it is making a clicking sound when I pedal. The sound ...
5
votes
4answers
523 views

for a single-speed conversion, is it always necesary to change bottom bracket?

I want to convert my old raleigh, which has 3 chainrings on the front, into a single-speed. Do I have to replace the bottom bracket? I keep hearing conflicting things. Thankyou.
5
votes
3answers
3k views

Does my bottom bracket need replacing?

About two months ago I bought a Boardman HT Comp. Today I took it into my local bike shop for a service. While I was in the shop one of the technicians had a quick look at it and told me that my ...
5
votes
2answers
828 views

Is the plastic sleeve optional for a GXP bottom bracket install?

I took my frame to a bike shop to have the threads chased on the drive side. When I got home, I realized that they didn't install the plastic sleeve (because I didn't give it to them). They didn't ...
5
votes
2answers
1k views

Is it possible to replace bearings in Shimano XT bottom bracket cups?

Curious if I can just replace the bearings in my existing cups or if I would need to buy new cups? If possible to replace them then what are possible high quality replacement bearings?
5
votes
3answers
786 views

Bottom Bracket Creaking

I have a 1993 Rockhopper frame that I'm riding as a singlespeed. I have some creaking around my bottom bracket. I've just recently stripped and painted the frame, and there wasn't anything ...
5
votes
2answers
242 views

Creaking bottom bracket

I have a Trek 3900 Mountain bike that had a serious creaking problem whenever I would pedal. I found that the ring that holds the Shimano sealed bearing was really loose. I tightened it up and it ...
5
votes
2answers
1k views

How can I keep my chain from falling off the inner chainring? (specifically, from getting stuck in the bottom bracket)

I've got a mountain bike which occasionally drops the chain off the lowest gear, and then the chain gets stuck in the bottom bracket. This happens while pedalling. Once the chain is there, it takes ...
4
votes
3answers
440 views

Crank arms are not parallel to each other. What could have caused this?

It is a cottered crank. Crank arms themselves don't seem to be bent. It is a non-cartridge style spindle. Any ideas as to why they are not lining up?
4
votes
2answers
182 views

Swapping cranks, but the new crank is wider, how do I compensate for this?

I was swapping the cranks and bottom bracket on my karate monkey from a Truvative stylo crankset (Mountain Double, GXP bottom bracket) to a Race Face Evolution DH (Mountain Triple, Race Face bottom ...
4
votes
2answers
9k views

How do I measure a bottom bracket?

I need to replace the bottom bracket bearing on my fixie. I plan to get a Shimano UN26, but I note that there are a number of different sizes. The sizes seem to be expressed as 68-110, where 68 is the ...
4
votes
4answers
319 views

English vs Italian bottom bracket - chainline considerations

I'm planning a new build and for the first time, I'm working with a frame that requires an Italian bottom bracket. My question isn't specific to the build, but a general question about chainline. ...
4
votes
2answers
386 views

Which Phil Wood bottom brackets are compatible with Shimano XT cranks?

As far as I can tell just the Outboard BB is.
4
votes
3answers
335 views

Clacking noise as right crank goes 'over the top' once per revolution

Every time the right pedal goes over the top I get a single clack noise with a little more 'travel', a point where the bottom bracket moves without any resistance, from that point in the rotation. I ...
4
votes
1answer
1k views

How can I tell the difference between a J.I.S. and ISO square taper bottom bracket?

I have a square taper bottom bracket. How can I tell whether it is a J.I.S. or ISO taper with a minimum amount of disassembly? FWIW, it's a Ritchey from 2004. However, it would be nice to get answers ...
3
votes
4answers
2k views

Bottom bracket making noise, should it be fixed now or can I wait until regular maintenance?

My bike has been ridden 4 months / 2000 miles and is no longer completely quiet. About a month ago I noticed a whispering noise like a wire brush sliding across a cymbal. It happens on the ...
3
votes
2answers
421 views

screeching/grinding sound when coasting at speed

2003ish Cannondale six13, all Ultegra. Frequently, but not always, when I'm coasting at a fast pace, usually down a hill, the bike will start making this hideous screeching/grinding noise. It is ...
3
votes
2answers
2k views

Can a bike with an internal bottom bracket be retrofitted to have an external bottom bracket?

External bottom brackets have been appearing on higher-end bikes in the last few years. Can older bikes with bottom bracket shells that come stock with square taper internal ISO 68mm or oversized ISO ...
3
votes
2answers
381 views

Cutting down cartridge bottom bracket left cup

I have a Tange 68x103 mm bottom bracket (pictured) that I plan to use in an old steel frame (building a single-speed/fixed). It turns out that my non-drive-side bottom bracket shell threads were a bit ...
3
votes
1answer
596 views

Will I damage anything by not replacing my clicking bottom bracket?

I have a Specialized 2010 Sirrus Sport with a sealed cartridge square taper bottom bracket that makes a clicking noise. If I don't have it replaced, will I be harming anything apart from the bottom ...
3
votes
2answers
367 views

Chainline on a trek 660 fixie conversion

I am converting an old Trek 660 frame to fixie. It takes a 68mm bottom bracket and I'm putting in an SKF bottom bracket (like this) with both a BMX profile racing 110mm 46t and redline BMX cranks ...
3
votes
1answer
1k views

How hard is it to disassemble and reassemble a bottom bracket?

I ride an SE Lager. It's a pretty cheap and crappy bike. I've had to replace pretty much everything on it due to wear/breakage. The only area I haven't tackled is the bottom bracket. I can ...
3
votes
1answer
100 views

Thinking of getting a new chainset

I've decided to get a new chainset as my current 38T Nexus is giving low speeds with my Alfine 8 speed hub. I have my eye on the 45T Shimano Alfine chainset. Currently I have a square taper bottom ...
3
votes
1answer
455 views

Bottom bracket square taper (cartridge) extraction, too tight in one side

I'm getting weird noises coming from the bottom bracket (BB from now on), and I wanted to extract it to check if the problem is there or not. The guide video I used is no longer public (free) as when ...
3
votes
1answer
763 views

Are Shimano Hollowtech II bottom bracket spacers unique?

I'm moving my Shimano Hollowtech II XT crankset and bottom bracket over from a bike with 73mm bottom bracket to a 68mm bike. The only problem is that I only have 1 spacer and now I need 3 bottom ...
3
votes
2answers
581 views

What road double cranksets will work with a 108mm JIS square taper bottom bracket spindle?

So far it seems like the Shimano Sante or Suntour Sprint cranksets are the only ones that would fit my bottom bracket spindle (I am hoping to keep both BB and spindle). Am I missing any possible ...
2
votes
4answers
2k views

Cross threaded/stripped bottom bracket

I installed a new sealed bearing in my bottom bracket. Unfortunately after tightening it most of the way, it jammed and I realised I'd cross threaded it. I then removed it and reinstalled it. It ...
2
votes
2answers
171 views

What do you call the crankset system type on the Sram Apex?

I see these everywhere, but no one can come up with a consistent name for them from company to company. GXP is the closest I can come to a name for the bottom bracket. ...
2
votes
2answers
373 views

What sort of bottom bracket does a Trek 1.5 2011 take?

My bottom bracket is on its way out.. No longer getting smooth rotation even without chain attached. I was wondering if anyone knew what sort of bottom bracket the frame supports? I've googled but the ...
2
votes
1answer
180 views

Why does my non-drive side crank arm come loose?

I tighten the bolt super hard. Ride for a while. Then it comes loose again. I don't know if its my BB or the bolts. How can this be fixed??
2
votes
4answers
541 views

Bottom bracket with built-in internal hub - does this exist?

I've heard that one can install a bottom bracket that has what is essentially a built-in internal hub, giving one the ability to add a virtual double chainring where there's only one. This would be ...
2
votes
4answers
522 views

Cruiser bottom bracket is clicking and grinding

My Trek Pure Deluxe 3-speed cruiser has been making a clicking noise when riding for some time. The problem is faint, and is more felt than heard. However, it's been getting worse; it now makes a ...
2
votes
3answers
208 views

Failing to unscrew BB - what now?

I have an external bearing BB, that I need replaced (It is quite badly rusted). I opt to do the repair myself. The bike is a Specialized Hardrock, the crank arms are SR Suntour. Having removed the ...
2
votes
2answers
190 views

Identifying bottom bracket

First and foremost.. I'm slowly trying to replace my bottom bracket.. it makes a kind of knackered-bearings sound when I move the pedals round without the chain attached. This is because I've been bad ...
2
votes
1answer
454 views

DBS 10 Speed Conversion - Bottom bracket?

I have dismantled and thrown away the old parts of this DBS 10 Speed bike I'm converting to a fixed-gear. Yesterday I received a 48T Espresso crankset, but now I wonder which bottom bracket to get. ...
2
votes
1answer
331 views

Can if fit new 105 5700 cranks on my existing 5600BB?

I am refreshing my drive train. I have been running a full 105 5600 set for a couple years. I have an ultegra cassette and chain ready to fit, and I am consdiering crankset/chainring options. Is the ...
2
votes
2answers
139 views

What is causing noise/vibration high power input on right hand (drive side) crank?

I am getting a repetitive grinding sound/slight vibration while fully mashing on my Kona-humu single speed. Description of Problem This grinding is more similar to what you would hear from an ...
2
votes
2answers
608 views

Attaching crank arm with Shimano SLX M660

Firstly, apologies if this question has tones of frustration, my new crank set and bottom bracket has never been installed correctly, so I am going to do it myself. Should the drive spline on the ...
2
votes
2answers
498 views

Bottom bracket bearing Issues

Been having some bottom bracket (BB) woes. Noticed a click on the top of the left pedal stroke decided to re-grease the BB. Took it apart cleaned everything re-greased, put it back together. Roll ...
2
votes
1answer
723 views

Swap Bottom Bracket bearings or replace entire bottom bracket?

I've recently acquired a 2007 Specialized Allez. As I was dismantling the bike for service, I discovered that the bottom bracket bearings are in rough shape. They aren't smooth at all. I took apart ...
2
votes
0answers
88 views

Claud Butler Tandem - transmission issues

I'm in the process of stripping a SWB Claud Butler tandem so I can get it repainted. There are a couple of things I need help with.... a) Can you fit a front mech to the bike, and if so, are there ...
1
vote
3answers
1k views

Bottom bracket is ticking

Recently my 2008 Devinci mountain bike sounds like it's ticking when I push down on my left pedal on a usual rotation. When I turn the bike over and go through rotations, I can't get it to tick. ...
1
vote
2answers
901 views

Will a hollowtech shimano BB fit a bike which currently has an octalink bracket?

I have a mongoose otero elite 2008 and the crankset is broke (wobbling) It's also bent, so time for a new one. I currently have a nice shimano deore crankset from an old bike, but it uses a different ...

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