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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22 views

Bottom Bracket - Drive Side is Stuck, what to do please?

I'm trying to remove a sealed cartridge BB. I've removed both cranks and the non-drive side (plastic) came out fine. The drive side is stuck solid - I know it's reverse thread on the drive side and I ...
3
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2answers
58 views

Why is there a gap between my crank and bottom bracket?

I just fitted a Tiagra crank arm to my bike. I noticed that there was a gap between the bottom bracket and arm and was concerned whether I fitted the arm correctly. I tried to force the crank arm ...
4
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1answer
30 views

Crankshaft snags and loses resistance while cycling

I have a hybrid (18+ years old) that I use for daily commuting which has developed a problem with the cranks. Every so often (perhaps 10% of the time) when I push down on either crank arm after ...
4
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1answer
57 views

Difference of bottom bracket cup materials: resin, plastic, metal

Bottom bracket cups are made of different materials. What are the pros and cons of the materials? What experiences do you have with them? The metal could be problematic due to galvanic corrosion ...
4
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1answer
40 views

On a bottom bracket, what does the numeric expression e.g. 1.37x24 mean?

On a bottom bracket I can read 1.37x24 - what do 1.37 and 24 stand for?
7
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1answer
58 views

Does the BB axle (spindle) lengths 1:1 compare for square taper and octalink?

When measuring the axle length of a square taper bottom bracket, can I pick a new octalink bottom bracket with the same axle length? I can think of some offset added or removed by the difference how ...
3
votes
1answer
102 views

Will this power2max power meter be compatible with Cannondale Synapse?

I have a 2015 Cannondale Synapse - specifically, this one: http://www.swiftcycles.co.uk/334/products/2015-cannondale-synapse-carbon-105-6-road-bike.aspx. I would like to add a power meter, and ...
4
votes
3answers
168 views

Could I use a 30 tooth chainring with my current crankset?

a few months back I installed a 34 tooth narrow-wide chainring in my Santa Cruz Bronson. I decided to install the 34 tooth chainring, basically, because I couldn't fit any other smaller chainring ...
3
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1answer
145 views

How do I convert a Shimano Selecta to something more modern and quality?

I have created a single speed bike out of a 1982 Helkama Kulkuri. The only part that is a mystery to me is the bottom bracket (BB). It seems it is an interesting and easy to work with Shimano Selecta. ...
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2answers
63 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
65 views

What is an attached bottom bracket?

Reading the specifications of a Merida Reacto 500 (2015) I noticed that at the bottom bracket is Attached, I only ever read about brackets threaded in the frame or press fit brackets.
4
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2answers
54 views

What direction are the threads on Ultra Torque bearing cups?

I need to remove the bottom bracket bearing cups from my 2010 Athena groupset. Do they both unscrew anti-clockwise, or is one side different (and which one)?
3
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1answer
81 views

How to remove a seized bottom bracket from a titanium frame?

I can't loosen it even with a long breaker bar.
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1answer
68 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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0answers
51 views

Purefix Kieren Pro

TL;DR FRAME: Kieren Pro (68mm BB) Which BB is suitable for this frame? (want to use SRAM s100 crank) If BB must be Truativ 108 or 113mm, how do adjust chainline? Thanks for your time and efforts ...
5
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2answers
457 views

Pros and cons of gears in bottom bracket vs. rear hub? [duplicate]

Since 6 years, I am the happy user of a bicycle with a Rohloff internal hub gear. German quality squeezing 14 gears and a 526% gear range into the rear hub. Less known is the newer and equally ...
0
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3answers
90 views

Bottom bracket creaking only when pedaling hard.

When pedaling with a decent amount of force a very loud creaking sound can be heard coming from the bottom bracket area (it is very loud when standing on the pedals). It makes a creaking noise on each ...
3
votes
2answers
213 views

Bottom Bracket Lube?

Lately, after my normal wash & lube routine, I've been squirting a little Teflon lube into the bottom bracket hub. I do so without dissembling by inserting the lube straw into the hub crevice. Is ...
3
votes
2answers
118 views

What should I do with my crank/bottom bracket?

I just got this mountain bike almost 3 weeks ago. I took it for a long ride(120km back and forth). We encountered heavy rain during our ride, we were riding on a highway back then, there's flood water ...
2
votes
1answer
57 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
votes
1answer
93 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 ...
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1answer
263 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 ...
2
votes
1answer
72 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 ...
5
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1answer
150 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
votes
1answer
52 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
votes
1answer
231 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 ...
2
votes
2answers
185 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
2answers
289 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 ...
3
votes
1answer
118 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 ...
5
votes
1answer
878 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 - ...
0
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1answer
145 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
159 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
votes
4answers
464 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 ...
0
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1answer
209 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. ...
0
votes
2answers
60 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
282 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 ...
0
votes
1answer
120 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 ...
1
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1answer
157 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 ...
0
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1answer
242 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
41 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 ...
0
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1answer
555 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) ...
0
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3answers
285 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 ...
0
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1answer
1k 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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votes
1answer
140 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 ...
0
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1answer
632 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
155 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
63 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 ...
0
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2answers
742 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 ...
0
votes
2answers
138 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 ...
1
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2answers
221 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 ...