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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1
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2answers
329 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 ...
0
votes
1answer
263 views

Can't get the drive side bottom bracket cup out

I have an older Raleigh frame that I converted to a fixed gear and the bottom bracket cup on the drive side has been painted over a few times and I can't get it out. This is the type of cup (the one ...
0
votes
1answer
151 views

Windsor - The Hour - Bottom Bracket Dimensions

I'm looking to replace the bottom bracket in my Windsor "The Hour" since I'm buying a new crank set for my bike. What are the dimensions for the bottom bracket: both shell width and shaft length? I ...
5
votes
2answers
852 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 ...
3
votes
2answers
583 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 ...
1
vote
2answers
374 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 ...
2
votes
1answer
139 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>- ...
1
vote
1answer
335 views

Shimano Ultegra Bottom bracket replacement with Dura-Ace

The bottom bracket on my Van Nicholas Astraeus is a creaking when going up hills. It's already been tightened recently, yet seems to creek more and more lately - probably due to the mileage (many, ...
2
votes
1answer
1k 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 ...
2
votes
1answer
272 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 ...
1
vote
1answer
161 views

bottom bracket Stronglight JP400 equivalents

I need to replace my bottom bracket cartridge because it is knackered. After a bit of reading it seems that there may be many types of cartridge variations (axle lengths, threads, size of square ...
2
votes
3answers
446 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
1answer
192 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
2k 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 ...
5
votes
2answers
975 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 ...
2
votes
2answers
696 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
908 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??
5
votes
4answers
642 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. ...
3
votes
0answers
127 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
2answers
566 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 ...
1
vote
1answer
175 views

How can I use a small Shimano BB on any frame?

I have a Shimano BB-ES25 bottom bracket and 45T crankset that was removed from a Giant-CRX City with an eccentric hub (it had Shimano Alfine internal hub gears). They have literally never been used, ...
2
votes
2answers
380 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
3answers
332 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
287 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
2k 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
2answers
797 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 ...
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 ...
7
votes
4answers
265 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 ...
6
votes
4answers
935 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.
1
vote
2answers
294 views

New rocky mountain soul 29 making creaks by the bb

Not to sure what it's coming from I don't have the tools to take the crank off or adjust the bb. The funny thing I don't get is that the creak is gone the next time I ride my bike then when I may go ...
4
votes
3answers
704 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 ...
2
votes
1answer
1k 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. ...
9
votes
3answers
6k 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 ...
2
votes
2answers
678 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 ...
9
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, ...
1
vote
3answers
795 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
3answers
2k 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. ...
2
votes
1answer
883 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 ...
3
votes
2answers
553 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 ...
12
votes
3answers
7k 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 ...
0
votes
1answer
297 views

screeching noise in bottom bracket

There is a very loud screeching noise when i pedal hard on the down stroke. Be it moving off or climbing up a hill. It is not coming from the front wheel, which i originally thought came from brake ...
2
votes
1answer
548 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 ...
1
vote
2answers
360 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
4
votes
3answers
662 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?
1
vote
2answers
2k 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 ...
3
votes
1answer
904 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 ...
5
votes
2answers
18k 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 ...
1
vote
2answers
680 views

Koga touring bicycle bottom bracket loose, does it need replacing?

I have a 2009 Koga Signature high-end touring bicycle (internal hub gear, hub generator, half-open chainguard, ...). I'm cycling around 100 km/week (8½ km one-way commute) plus trips, so I've probably ...
1
vote
2answers
2k views

Stationary bike “clicks” when pedaling - crank axle is moving sideways. How can I fix this?

I've got this stationary bike, a York C202, which has developed a problem - namely it "clicks" when pedaling. This is highly annoying, as there's nothing I seem to be able to do about it. I diagnosed ...
3
votes
2answers
461 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 ...