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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1answer
112 views

Crank sliding horizontally through the bottom bracket

Was out biking today when I noticed the pedals were moving side to side, with the pedal arm almost coming off the left side. As I was investigating the washer with "LH fsa AL" actually came off in my ...
2
votes
1answer
241 views

Older Motobecane conversion

I recently acquired an older blue Motobecane Mirage with a great frame and paint. I have stripped it all down and salvaged everything I can (frame, front wheel, handlebars, front brake) but now I'm ...
2
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2answers
2k 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
2k 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
879 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
1answer
80 views

Stuck Bottom Bracket

I have an 80's Fuji bike and It's definitely well past time to replace the bottom bracket. The adjusting cup came off fine, but the crank side cup is super stuck. I've tried stacking lockring washers ...
2
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2answers
326 views

Replacing crankset on early-'70s Motobecane 10-speed

I need a replacement crankset for my Motobecane Nomade 10-speed road bike (early '70s model), but am not quite sure what I even have at the moment and, once I know what I can use to replace it with, I ...
2
votes
1answer
222 views

Bottom bracket bearings grinding only when installed into frame

I recently purchased a new carbon frame direct from a Chinese manufacturer (link to the particular frame here). The frame has BB86 bottom bracket. I am using the SRAM Press Fit GXP BB86 Bottom ...
2
votes
1answer
131 views

Rat a Tat noises coming from my bottom bracket area. Please help!

I recently got my single speed frame and forks powder coated and at the same time had a number of parts replaced - bottom bracket, chain ring, chain and freewheel cassette. Really please with ...
2
votes
1answer
305 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 ...
2
votes
2answers
928 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
1k 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
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2answers
2k views

How to upgrade a dust cap?

For all you mechanics out there I am sure you hate these things. Dust caps are the bane of my existence. They are cheap and bend easily. I want to get a better sturdier one for a bike I am working on. ...
2
votes
2answers
445 views

How many spacers I can put on a Shimano hollowtec 2 BB for a 68 mm BB shell

My bottom bracket shell is 68 mm English thread. I put a 1 mm spacer on the drive side BB to move the chain rings further away from the frame, so to prevent the chain rub against the inside of the ...
2
votes
2answers
271 views

Creaking From Bottom Bracket [duplicate]

I'm not too familiar with the correct terminology for bike parts so please bear with me. I recently bought a mountain bike and have started to notice a loud creaking sound coming from the pedal/...
2
votes
1answer
1k views

Are these compatible bottom brackets?

I have a LeMond Big Sky SLT & an Opus Triton. Every bikepedia-esque site I went on said they had incompatible bottom brackets. When I actually read the brackets today the LeMond has a BSA. The ...
2
votes
1answer
502 views

How can I prolong the life of my bottom bracket bearings?

I have a bike with Campy components. I've found I need to replace the bottom bracket bearings annually, which is expensive and inconvenient. I do less than 2000km per year on it, largely through ...
2
votes
1answer
879 views

What types of BB-axle to crankarms interfaces are there?

On the lowest end, we have the taper/square interface. I believe it is standard i.e. there are no variations in the sizes. image property of VP Components USA Then there is the octalink. Actually ...
2
votes
1answer
319 views

Yet another stuck BB. Help me save my frame!

So I have two bikes and a year ago I went through the challenge of unscrewing a stuck BB. The solution was to put the tool in a vice and twist the frame around it. Today I have an even more difficult ...
2
votes
1answer
183 views

Raleigh AT20 series bottom bracket affects derailleur

I took out the bottom bracket to clean it etc taking off the pedal shafts etc - and when it came to putting it back - the front derailleur was well out of adjustment - Have I done something wrong>- ...
2
votes
1answer
513 views

Italian bottom bracket Shimano BB-6400 fixed cup tightening - what tool?

All, I have a Shimano 600 Italian-threaded bottom bracket (BB-6400) and after riding with it for a few weeks, the fixed cup is loosening. I've since read up about Italian BBs and learned that the ...
2
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3answers
546 views

I unscrewed the lockring, and *both* BB cups rotated - what's going on?

I'm fixing up an old tandem, and the cup-and-cone bottom bracket at the front sounds very gritty, so I picked up my c-spanner and applied it to the lockring. With a bit of effort, left cup and ...
2
votes
2answers
819 views

Bottom Bracket Size for Specialized Roubaix Elite C2 2009

I think my bottom bracket has worn and I would like to replace it. I was looking at the Shimano 105 BB. BikePedia lists the size as 68mm, which is fine, but there seems to be another dimension. I ...
2
votes
0answers
394 views

Serial numbers on bottom of a pedal crank housing from a 50s era Schwinn?

Can someone please explain what these three numbers mean on the pedal crank housing? I believe this to be the pedal crank housing from a 1956 Spitfire Ladies Bike. The Schwinn Serial reads M0D502 (...
2
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1answer
3k views

Replaced Shimano Bottom Bracket, now front derailleur won't shift to largest gear

OK, so in my quest to get my old Trek 7000 ZX MTB running again after a long retirement, I am having an issue with replacing the bottom bracket. The bike came with a Shimano LP25 that is marked BC 1....
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vote
2answers
903 views

Bottom bracket cup doesn't fit on non drive side

I'm replacing the crankset and bottom bracket on my old steel frame road bike, which looks like this one, so I'm guessing it's from around 1985. I picked up a 68 mm square taper bottom bracket and ...
1
vote
2answers
4k 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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vote
1answer
148 views

New bottom bracket, asymmetric cranks

I am seeking help for a "dilemma" I have with my upgraded bike. I have an old KTM Ultra Line (2004) that I have upgraded with a new chain wheel (FC-M590 48.36.26t), a Shimano BB52 bottom bracket (...
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1answer
41 views

How do I keep smallest gear on my crank shaft from contacting frame

I have an old Trek 8000 ZX that I am fixing up. I had to replace the bottom bracket and I believe I successfully did that. The bike did not have a crank set to work with so I salvaged one from a pile ...
1
vote
1answer
48 views

Are the Truvativ powerspline BBs reliable?

When I first got my Haymaker 1500 about 2 years ago the BB crank interface was the Truvativ powerspline pattern. In the first winter my left arm came loose when it was cold (-15*C or so). Since it ...
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1answer
227 views

Is anyone aware of specific problems with Vanmoof cranks/bottom brackets?

I have a 2013 Vanmoof 5.1. I had it serviced recently by Vanmoof in Amsterdam and when I got it back, it was riding wonderfully—everything felt smooth and "free", like every little bit of power I was ...
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3answers
1k views

Replacing bottom bracket on 98 trek 820

I'm trying to replace the bottom bracket assembly on my 98' trek 820. The current one grinds and needs replacement. The bracket that came in it is a shimano bb-ct92. I've looked online and can't ...
1
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3answers
2k views

Removing bottom bracket from 79 peugeot frame

I would like to remove the bottom bracket from an old french peugeot race frame. I believe the frame was built in 79 judging by the decals and stamp on the bb. The bottom bracket and spindle at the ...
1
vote
3answers
1k views

Noise from crankshaft spindle and then the pedal falls off

In the last 6 months I have been getting really bad noises, creaks, clunks, etc coming from somewhere around the spindle connecting to the crankshaft. Every time I put pressure down on the left hand ...
1
vote
2answers
639 views

how to replace a bearing on BB7800?

Friends, Do anyone of you know on how to replace a bearing on BB7800 ? Do I need a special tool ? or a screw driver, and hammer would be enough to push it out ? Thanks
1
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2answers
25 views

Disassembling crank on a 2006 Trek Pilot 2.1

I'm trying to disassemble the crankset on my 2006 Trek Pilot 2.1; the bike has all OEM parts. The crank is a Bontrager race crankset, which I'm to understand is a a rebranded Truvativ crank. For a ...
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vote
2answers
252 views

How much assembly is required when an LBS orders a bike?

I'm looking to order a Marin Lombard Elite from my LBS but I want to replace the FSA BB and crankset with Shimano or SRAM parts, and change to a 52/36. When my LBS orders it, does all of that come ...
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2answers
205 views

BB Lockring won't completely tighten

I am trying to put the lockring back on my BB after adjusting it to reduce the play, but I am unable to full tighten it. I can hand tighten the lockring, but as soon as I try to use my hook spanner to ...
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1answer
315 views

Tool for shimano bb-un26 Bottom Bracket

What tool do i need to dismount a shimano bb-un26 bottom bracket? Will a Park Tool BBT-22 work?
1
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2answers
5k views

Broken bottom bracket? Pedals are pretty loose

Unlike the rest of the broken bottom bracket questions, my bottom bracket does not make any noise or feel like anything is grinding. There is about 1/2cm of play left to right that i can see on the ...
1
vote
2answers
954 views

How to judge BB height visually and the effect on handling?

Is it possible by viewing a bike frame to tell roughly what the handling of the bike is going to be? This current question is about bottom bracket height in the above mentioned respect. I have ...
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3answers
2k views

How long does it take to replace bottom bracket bearings?

How long does it take to replace bottom bracket bearings? Is there anything that can make the procedure take more or less time? How does the type of mechanism affect repair time?
1
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1answer
97 views

Can a tapered BB be installed in either direction?

I have a tapered bottom bracket on my bike, like the one in the pic. On this bike, as I bought it, the fixed cup is on the drive side of the bike, while the adjustable cup is on the non-drive side. In ...
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vote
1answer
59 views

short cranks for new Brompton JIS bottom bracket

The bottom bracket on my new Brompton is this one (I believe): http://www.sjscycles.co.uk/brompton-bb-cartridge-jis-for-spider-crankset-119mm-prod31207/ It is a JIS BB with 119 mm spindle length ...
1
vote
2answers
208 views

Using Loctite for integrated head set and bottom bracket installation

I'm in the process of building up a new bike from scratch. Since the last time I have done this many things have changed, reading varios forums and watching numberless videos on YouTube have not ...
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1answer
80 views

Bottom Bracket issues

So I took the old bottom bracket out of my hybrid frame, FSA Platinum ISIS Bottom Bracket 68 x 118mm. I then replaced with a Shimano BBUN55 Square Taper 68 x 11.8cm. Then realised that this was a ...
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1answer
77 views

A gap in the hole when inserting JIS square BB to a Truvativ Crank

I push the BB inside a crank hole without any tool but I expect a few milimeters gap. The Truvativ crank definitely uses JIS interface, but the question is: DOES the gap make any problem? or is it ...
1
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2answers
479 views

How do I know what is the right bottom bracket for my old road bike?

I've got an old road bike. I'm not exactly sure what the frame is as it was repainted. I've reason to believe the that bottom bracket is wrong because the crankset ring is too close to the chainstay. ...
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1answer
86 views

How do I remove a bottom bracket?

I have managed to remove the threaded locking mechanism of this bottom bracket. However, I can't get the bracket out. I have tried to just bang it out, but it doesn't move. I don't know what else to ...
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1answer
1k views

How tight should a threaded BB be?

I have an english-thread, octalink Shimano bottom bracket, and a new frame. The frame has been faced before painting. I am not sure the BB is compatible with the frame. When trying to install the BB,...