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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23
votes
13answers
64k 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. ...
13
votes
6answers
18k 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
8k 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
7answers
15k 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, ...
10
votes
2answers
8k 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 ...
9
votes
3answers
7k 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 ...
7
votes
4answers
271 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
2k 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 ...
6
votes
4answers
994 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.
6
votes
3answers
979 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 ...
6
votes
3answers
870 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 ...
6
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?
6
votes
2answers
2k 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 ...
6
votes
1answer
3k 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 ...
5
votes
2answers
1k 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 ...
5
votes
2answers
5k 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
371 views

Bottom bracket removal, what is this part?

I have a new (old) bicycle, and I am in the process of disassembling it. I arrived to the bottom bracket (with a cottered crank), and unscrewed the ring without problems, but then I'm faced with a ...
5
votes
2answers
1k 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
19k 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 ...
5
votes
4answers
665 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. ...
5
votes
2answers
504 views

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

As far as I can tell just the Outboard BB is.
5
votes
2answers
968 views

How should I prepare a carbon frame when I want to swap in a new bottom bracket?

My four-year-old, carbon-framed road bike has developed a case of creaky cranks. I only hear creaking when pedalling hard, when I pedal more softly it just sounds like it has always done. Given the ...
4
votes
3answers
684 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
1k views

How to replace old style cotter-pin bottom bracket with a modern one?

I have an old 1950's English bicycle with cotter-pin style bottom bracket like this: I find the cotter pins fail fairly regularly and are hard to replace correctly. I was wondering if it's possible ...
4
votes
2answers
500 views

Why does the chain tension vary as pedals are turned?

I have a new single-speed bike (after purchase this year, it was unused in a garage for a few months), but as I turn the pedals, the tension in the chain varies noticeably. What should I check, ...
4
votes
4answers
745 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 ...
4
votes
1answer
498 views

What tools do I need to replace my bottom bracket?

I have an old 2001 Schwinn Homegrown Pro that I want to upgrade to a 10-speed drivetrain. I'd like to do it myself as a learning exercise, but I'm not sure what kind of tool I need to remove the old ...
4
votes
1answer
158 views

If external bearing BBs are better, why use traditional ones?

Related: What are the benefits of external bottom brackets? An outboard BB includes any BB which uses the same BSA or Italian threading as older style BB's, but places a larger bearing ...
4
votes
3answers
756 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
294 views

What went wrong with my bottom bracket spindle length calculation?

Here's the facts: My bike frame requires a 70 mm Italian threaded bottom bracket I'm going to use a Nuvinci N360 IGH which requires a chainline of 49 (± 0.5) mm. I have Andel fluted cranks, which ...
4
votes
1answer
237 views

How do I tell if I've correctly installed a press fit bottom bracket?

So I bought a Chris King PF30 bottom bracket and pressed it in using a bearing press along with the bushings that came with the Park Tool bbt-30.3. Using the bearing press I pushed both cups in ...
3
votes
4answers
4k 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
4answers
109 views

Noticeable clicking from crankset or bottom bracket

A few days ago I began hearing a clicking noise coming from the crankset and I can also sense a slight hitch when the right crank is at its upmost position just when it's about to go down. The ...
3
votes
2answers
631 views

How can I remove the bottom bracket from this old road bike?

I need some help removing this bottom bracket. I am obviously no mechanic, and watching several videos on youtube I found nothing that could help in this specific case. Basically after removing both ...
3
votes
2answers
764 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
4answers
1k 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 ...
3
votes
2answers
3k 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
1answer
2k 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
2answers
561 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
942 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
466 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
2answers
61 views

Replace asymmetrical BB with symmetrical cartridge and spacers?

My bike has a square taper 68mm width cup and cone bottom bracket that is wearing out. I was hoping to replace it with a sealed cartridge (shimano UN55 or similar) but then I found that the spindle ...
3
votes
1answer
637 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
934 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
1answer
383 views

Can I measure my bottom bracket size without removing the cranks?

I don't have a LBS (there are BS, but not L), so I generally order everything I need online. I need to replace the bottom bracket on my commuter bike, which I know is a VP-BC73 but that BB's available ...
3
votes
2answers
319 views

Do I need to face my new frame?

I just purchased a new aluminum MTB frame. The headset is a standard "NECO, 142, 1-1/8” AHEAD". The BB is ... I'm not sure, but is internal and threaded. How do I determine if I need to face or ream ...
3
votes
2answers
955 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 ...
3
votes
0answers
116 views

Do Miche bottom brackets require a special tool, or is this one damaged?

I just bought a Miche Primato bottom bracket and tried installing it using Park's BBT-5 (the same tool I used to remove the previous bottom bracket, also Miche, but from 2008). The BBT-5 fit into the ...
3
votes
0answers
129 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 ...
2
votes
4answers
4k 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 ...