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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69 views

What is the purpose of greasing BB threads?

As is known for Shimano sealed bottom bracket cartages (e.g. page 16 here), if the BB cup is made out of metal, grease should be applied to the frame-cup thread. If the cup is plastic, grease should ...
1
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1answer
49 views

Giant Defy 2 Bottom Bracket

I'm considering upgrading to an Ultegra groupset, found a very good price online, but I do not know what bottom bracket is in my bike. I have a 2015 Giant Defy 2, aluminum frame, and to me, this looks ...
1
vote
1answer
43 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 ...
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0answers
67 views

Bottom Bracket Compatability Question

Good afternoon all! In previous questions, I've mentioned that I intend to rebuild my 2000 Trek 7700 Multitrack. Well, I'm beginning by replacing the bottom bracket. According to the spec sheet I ...
2
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1answer
25 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 ...
3
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1answer
120 views

I can remove crank arms without a crank puller, is this a problem? I'm worried the crankarms might be loose

Currently, I'm little bit worried about the compatibility of my crankset and the bottom bracket. The crankset is Truvativ Isoflow, the BB is BB-UN55 (Square taper). Yesterday, after the bike hit +1400 ...
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0answers
89 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
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2answers
110 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
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1answer
58 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 ...
3
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0answers
297 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 - ...
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1answer
101 views

What bottom bracket do I need for a decathlon rockrider 5.0

The bottom bracket on my Rockrider 5.0 has a little too much play in it so I figured it best to change it before I get a failure whilst I'm commuting. Does anyone know which bottom bracket I would ...
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2answers
109 views

How does pedaling power transfer to the bearings in Hollowtech II bottom bracket?

I just installed a Shimano Hollowtech II crank and bottom bracket on my bike, and I'm wondering how they work together. My understanding is that the bearings are located in little cups that screw ...
3
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4answers
262 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 ...
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1answer
125 views

Help me understand bottom brackets and cranks

I have a Norco Threshold cyclocross bike (http://www.norco.com/bikes/road/cyclocross/threshold-carbon/threshold-sl-ultegra/) . It has a PF30 bottom bracket and an FSA Energy Cross PF30 46/36T crank. ...
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2answers
45 views

Replacing my bottom bracket. I need help IDing a replacement

So I have owned a Swhinn Network 3.0 (21-speed. Square tapered BB. All aluminum) for almost 5 months, and at about month 3 the bottom bracket started giving me some noise. I work in a bike shop on my ...
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1answer
150 views

Praxis Bottom Bracket Performance on BB30 Frame

I'm looking at upgrading the crank (stock FSA to Force 22) and getting a Praxis BB for my Cannondale CAAD10 BB30 frame. http://www.praxiscycles.com/product/conv-bb-sramgxp-isis-2/ It seems like ...
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1answer
82 views

Bottom Bracket Press fit to a square taper

I like to use my old Campagnolo crank on a new road bike frame. The frame has already a Pressfit BB71-41A installed. The crank needs a sqaure tape. Is it possible to use the crank with a adapter or do ...
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2answers
78 views

Finding a replacement crankset (and maybe a bb to go with)

I am in need of replacing my crankset on my hybrid discovery 401 - although all that is left of the 401 now is the frame and the bb/crankset. it has a sealed bb 113/68 square taper. I am struggling ...
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1answer
128 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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1answer
158 views

Crank fell off square taper BB. Should I replace bottom bracket

After years of use and multiple retightenings my crank will fall off my bike about once a week and definitely needs to be replaced. I believe that the square hole of the crank has expanded to the ...
0
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1answer
32 views

Campagnolo 1973 strata cranks(BMX) help

I am installing them on a very rare BMX frame.the bottom bracket shell measures 66mm.I believe I'm looking for a spindle length of approximately 110mm.it also has to have English threads.my question ...
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1answer
345 views

Shimano Hollowtech II bottom bracket: milling the frame necessary?

In a bike shop I recently asked for bottom brackets. The seller said, when choosing a Hollowtech II bottom bracket (like SM-BB70), compared to Octalink/square taper bottom brackets the outer (lateral) ...
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3answers
182 views

Trouble Removing bottom bracket. Is it my Tool?

I'm having trouble removing my bottom bracket. I'm using quite a bit of force as far as I can tell. But neither side is budging. The bike is a 2011, and I've never removed the bottom bracket, but ...
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1answer
641 views

How to fit BB bearings to install Ultegra Crank on road bike Wilier Cento 1

I've bought a used Wilier Cento 1 carbon road bike frame (not the new Cento1SR, but the previous model). Now I would like to transfer all Ultegra 6700 groupset components from my existing bike to it. ...
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1answer
113 views

Frame not faced for BB. Strip the paint or leave as-is? [duplicate]

So I just got my new frame from the LBS. They were supposed to face the frame, but only faced the head tube (hopefully, can't check it since the headset is already installed.). Sadly, they didn't ...
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1answer
346 views

Technical documentation for Shimano FC-M510

I'm having a hard time finding the technical documentation (equivalent of https://www.dropbox.com/s/yx5hq4cezpdz641/alivio-crankset-service.pdf?dl=0) for the Shimano Deore Hollowtech 1 crankset, ...
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1answer
92 views

Over-tightening a BB

I just installed an external bottom bracket (Hollowtech II type) on my steel bike. The manufacturer (Sugino) prescribes a 40-50Nm torque. I own no torque wrench, so I just wrenched it on pretty tight. ...
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1answer
60 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 ...
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2answers
350 views

Do I need to chase a thread before installing a bottom bracket on a new frame?

Currently I'm building a new Surly Cross Check, and it needs a 68mm BB (english threaded). Furthermore, I plan to use a cheap $15 shimano BB with JIS square tapered interface, nothing special. Do I ...
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2answers
131 views

What kind of bottom bracket fixing is this?

Dismantled my bike to try and take a look at the crank bearing, as I fear it may be getting dry. Unfortunately at the stage pictured I could go no further. The outer and inner rings appear to be ...
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2answers
181 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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1answer
155 views

Why is my electric bike 'clanking' under load?

I have a Giant Esprit Twist Power electric bike, which apart from not having nearly enough words in its name also has a problem related to the crank. When I put a lot of load through the pedals there ...
3
votes
2answers
138 views

Converting from square spline to external bearings, what do I need to know?

I need to replace the entire drivetrain on my circa 2000 MTB commuter. Quality groupsets all seem to use external bearings these days. Replacing my current cartridge bottom bracket for a modern ...
0
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1answer
448 views

Which bottom bracket do I need to replace crank on a Trek FX 7.1?

I have a Trek FX 7.1 that I've rode for several years now and replaced parts as they've worn out. Now I'd like to upgrade the whole drive train with Tiagra 2x10 flat bar shifters, derailleurs, crank, ...
1
vote
1answer
127 views

Q-factor of external bearing BBs

Seems to me that the Q-factor for an external bearing bottom bracket will be greater than that of an equal size (say, 68mm road bike BB) cartridge bearing. Is that the case?
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2answers
248 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. ...
2
votes
1answer
144 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
1k 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 ...
3
votes
1answer
157 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 ...
0
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2answers
86 views

Need help identifying bottom bracket

I need some help identifying my bottom bracket. One of the bearings is in a very bad shape and needs to be replaced. Bottom bracket photos
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2answers
169 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 ...
0
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2answers
920 views

What are my options for replacing a Shimano Hollowtech II BB?

I have had a 'Deore' equipped mountain bike for 3-4 months now. However, there is grinding noise from the area of the cranks and I suspect the bottom bracket. On a local MTB forum I heard that Deore ...
2
votes
2answers
136 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
1answer
192 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 ...
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3answers
621 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 ...
3
votes
2answers
553 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 ...
2
votes
1answer
117 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 ...
0
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0answers
264 views

Choosing the correct Bottom Bracket

I have a 2011 Commencal Supreme DHV3 Team edition and I need to replace the bottom bracket. The problem is that I am confused about what the correct model to buy is. The tech book for the bike ...
0
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1answer
264 views

Loose pedals on Norco MTB

Just replaced my pedals on a very old Norco MTB. I noticed while working on it that the whole peddle structure is wiggling from side to side is this normal ? I took the plastic caps off the base to ...
0
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2answers
464 views

FSA Omega MegaEXO Press fit BB 19mm removal (non standard BB86)

Has anyone removed a 19mm spindle (Omega) Press fit bottom bracket without destroying it in the process? I have watched http://www.fullspeedahead.tv/video/7006668/installation-of-megaexo-crankset-on ...