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
34 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
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1answer
88 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. ...
4
votes
2answers
123 views

Cutting off welded crankarm

A long time ago, when I was younger and stupider, I decided to fix my creaking crank arm by welding the bolt. Yes, I know it was so damn stupid, but I thought that was the problem. I didn't use the ...
3
votes
2answers
113 views

Bottom bracket replacement advice needed

I've got a Giant TCX SLR2 (2015) according to the spec sheet it has:- Crankset: FSA Gossamer Pro Cross, 36/46 Bottom Bracket: FSA MegaExo The other day I noticed the bottom bracket isn't sounding ...
3
votes
1answer
64 views

Replaced left crank arm but still comes loose?

A few weeks ago I bought a new (albeit cheap) self assembly bike from a local store, this bike to be exact http://tinyurl.com/gw77p9t . After about two weeks use (one and a half hours of cycling on ...
3
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2answers
66 views

How do I determine bottom bracket size [duplicate]

I got a cheap old bike I fixed up and I want to install a mid drive motor but the ones I found require a specific bottom bracket size and I don't know what size bottom bracket I have. The wheels are ...
0
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1answer
45 views

What is my bottom bracket spindle length?

I have this ubiquitous cheap Wal-Mart bike (http://www.walmart.com/ip/26-Roadmaster-Granite-Peak-Men-s-Bike-Black-Green/45089317z), which has a square taper bottom bracket. I'm trying to buy a new ...
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0answers
12 views

Bearing cap for Rotor BB30 to 24mm

I have a BB30 to 24mm adapter from Rotor. When installing the axle pushed out the bearing cap and I broke it trying to get it back in. What size replacement would I need? I'm not sure of the sizing ...
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1answer
32 views

Issue with PF30 BB on Boost frame - 2-3mm crank arm clearance

I have a brand new Titanium Boost 29er hardtail. The frame uses a PF30 BB and the BB shell is 73mm wide. I have installed the recommended RaceFace cinch PF30 bottom bracket with a Race face Next SL ...
3
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1answer
75 views

If chain/ BB/ casette are dead can chainrings and derailleurs still be OK?

I bought a brand new bike last May (2015 Brodie Elan) and proceeded to put 11,000km on it by November (cross Canada ride plus some commuting). Around the 11,000km mark I brought it back to the shop ...
2
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1answer
62 views

Trouble removing bottom bracket

I've got an FSA MegaExo bottom bottom bracket that seems to have gone bad. I've head that FSA doesn't have the greatest bottom brackets, so I was going to try to replace it with this Shimano bottom ...
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1answer
42 views

How does this work? “Rotor BB30 to 24mm Steel Road Bottom Bracket”

I'm looking at ways to make a Claris/Tourney crankset fit a BB30 frame. I've seen that a "Rotor BB30 to 24mm Steel Road Bottom Bracket" is one of the options to make the two sizes work together. ...
3
votes
1answer
33 views

Bottom Bracket size issues

I need to replace my bottom bracket on my giant rapid 3, the BB is a FSA BB-7420ST - 116mm (68x116mm), but it's hard to found or not available. My Question is: can I use a BB in 68x115 or 117mm ...
5
votes
2answers
45 views

Cartridge bottom bracket left cup is too tight?

Is it possible for the left-side of a cartridge-type bottom bracket to be too tight ? I followed the tightening torque instructions, and now the axle is not running as freely as when the cup is less ...
3
votes
1answer
35 views

Replacement or comparable model for my current Bottom Bracket

I am currently using a old mountain bike which is using a Shimano BB -LP26 / 68 x110 Size: BC 1.37x24 I am not sure if this model is with english treading or Italian treading. I understand the don't ...
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1answer
47 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 ...
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1answer
41 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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0answers
11 views

Canyon commuter bottom bracket noise [duplicate]

The bike is 3 months old and it had since the beginning a creacking noise that comes from the BB. As far as I know it is a SRAM gxp BB...should be good.... Now I can't ride the bike because of that ...
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1answer
68 views

Bottom bracket feels rough, should I replace it

My bottom bracket feels rough when I turn it with my fingers. I don't notice any problems when it's all assembled, but it's definitely not smooth like the other parts of much bike like my pedal axles. ...
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1answer
44 views

Crank Compatibility for my Orbea Hydro 2012

I have received as a gift a set of SRAM bb30 cranks. I would like to know if they fit my 1012 Orbea Hydro and if can I use SRAM Alloy GXP Bottom Bracket to fit it all together.
4
votes
2answers
113 views

Should I use anti seize for headsets and press fit bottom brackets in a titanium frame?

I have a shiny new titanium frame that I will be building up. I had the shop press in a headset and it looks like they used grease at the interface. Should they have used anti seize? I also need to ...
5
votes
4answers
178 views

Does (square-taper) BB spindle length affect Q factor?

I am having knee and ankle trouble on my commuting bike (1993 Specialized mtb) and this has a 73mm BB with a spindle length I haven't measured but there is space between crankarm and frame. I wanted ...
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1answer
47 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
votes
2answers
161 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
52 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
votes
1answer
79 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
64 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
votes
1answer
97 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
240 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
222 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
votes
1answer
233 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
169 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 ...
1
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1answer
82 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
votes
2answers
62 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
votes
1answer
96 views

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

I can't loosen it even with a long breaker bar.
1
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1answer
78 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 ...
0
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0answers
57 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
votes
2answers
1k 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
votes
3answers
102 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
409 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
140 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
74 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
103 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
vote
1answer
590 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
102 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
votes
1answer
235 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
98 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 ...
4
votes
1answer
355 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
298 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
420 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 ...