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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3
votes
1answer
736 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
4answers
195 views

Identify my Motobécane racing bike

I bought a Motobécane last year (pics below), and now that the bottom bracket is broken, I really need to know the model of the bike, to help me change that piece. It would also be helpful if someone ...
3
votes
1answer
144 views

Squeaking / Chirping while pedaling [duplicate]

I have a 2009 Specialized Allez Sport C2. When pedaling (actually only under load, not when just turning the crank while it's on a stand) the bottom bracket squeaks or chirps. I first thought it was ...
3
votes
2answers
1k views

how many spacers do I need for a 83mm bottom bracket and a 142x10 hub?

I have a Zee crankset on a 83mm bottom bracket (downhill bike). The Shimano manual says to use two 2.5mm spacers on the drive side, and one 2.5mm spacer on the non-drive side. However, this presumes ...
3
votes
1answer
2k 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
479 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
1k 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
6k 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
3k 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
2answers
442 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
1answer
933 views

What are the advantages/disadvantages of press fit bottom brackets compared with threaded?

Many standards for bottom brackets have been gaining popularity recently such as BB30 and PF30. What are the benefits of these press fit systems over the threaded system that has prevailed for ...
2
votes
1answer
4k 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
2answers
4k views

How to properly clean and lube the bearings on a sram apex bottom bracket (GXP)?

For this bottom bracket type I am not sure you can take the bearings out to lube them. How do I get grease in there. Also how do I get the old grease out? Does it even matter? I found this video ...
2
votes
1answer
19 views

Orienting Shimano Cup and Cone square-taper bottom bracket spindle

Let's say you were servicing a Shimano adjustable bottom bracket and forgot which way the spindle was originally oriented. You also forgot your ruler. How would one correctly orient the spindle (so ...
2
votes
2answers
132 views

Picking bottom bracket and chain set for older mtb frame

I have an old norco manik frame from 2006 and I need help picking bottom bracket and chainset. I have been looking at Truvativ Hussefelt 1.1 DH Chainset at crc but how do I make sure the bottom ...
2
votes
3answers
781 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
2k views

Does anyone have experience with Bottom Bracket Tap/Facing sets?

I'm interested in recommending my boss get the workshop in which I work a bottom bracket tap and facing set. As it's quite an investment it's important to me to know what you're getting for your ...
2
votes
2answers
1k 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
766 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
132 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
109 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
255 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
832 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
votes
2answers
1k 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
69 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
1answer
166 views

What's this noise? Is it from my crank?

I have recently been riding bmx, racing to be more specific. I ride around my neighborhood a lot when im not at the track and have noticed this loud clanking noise. I didn't know where it was coming ...
2
votes
2answers
211 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 ...
2
votes
1answer
669 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
333 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
223 views

Selecting a compatible BB: spindle offset

Replaced Shimano Bottom Bracket, now front derailleur won't shift to largest gear How do I measure a bottom bracket? I thought the only thing that mattered when replacing a bottom bracket ...
2
votes
1answer
201 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
votes
1answer
562 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
257 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
173 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
421 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
votes
3answers
471 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
706 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
1answer
46 views

Bottom bracket length without knowing front chainline (fixed gear)

I'm wondering if I can find the right bottom bracket axle (or spindle, whatever it's called) with knowing my crank model (Gipiemme Dual Sprint, Velobase says BB should be 113mm) and rear chainline (I ...
2
votes
0answers
155 views

BB92 (Shimano bottom bracket) with SRAM 30mm crankshaft (X01 or XX1 BB30)?

The frame that I want to build has BB92 bottom bracket hole. The drivetrain I want to use is 1x11 SRAM XX1 or X01 with 30mm crankshaft (BB30)(edit: also available GXP). There are ways to fit it - ...
2
votes
1answer
2k 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
vote
3answers
3k 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
3k 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 ...
1
vote
1answer
123 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 ...
1
vote
3answers
554 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
vote
2answers
654 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
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
927 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
518 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