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
140 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 ...
4
votes
1answer
63 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 free-...
4
votes
1answer
94 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
votes
1answer
84 views
7
votes
1answer
126 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
276 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. ...
5
votes
1answer
2k 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 - ...
4
votes
1answer
303 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 ...
0
votes
2answers
376 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 ...
5
votes
1answer
305 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
2answers
354 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 ...
3
votes
1answer
284 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
250 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 ...
1
vote
2answers
251 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 ...
2
votes
1answer
244 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 ...
1
vote
1answer
89 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
75 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
104 views
1
vote
1answer
80 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
votes
3answers
4k 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 ...
0
votes
0answers
61 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
119 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
757 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 ...
5
votes
1answer
874 views

Do Miche bottom brackets require a special tool, or is this one damaged?

I just bought a Miche Primato bottom bracket and tried installing it using Park's BBT-5 (the same tool I used to remove the previous bottom bracket, also Miche, but from 2008). The BBT-5 fit into the ...
3
votes
2answers
147 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
84 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 ...
8
votes
4answers
2k views

Creaking bottom bracket

I have a Trek 3900 Mountain bike that had a serious creaking problem whenever I would pedal. I found that the ring that holds the Shimano sealed bearing was really loose. I tightened it up and it ...
0
votes
1answer
2k 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. ...
0
votes
1answer
200 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 ...
5
votes
1answer
247 views

Claud Butler Tandem - add a front derailleur?

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
1answer
104 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
784 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
116 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 ...
4
votes
3answers
2k views

Expected chainline from 103 mm bottom bracket to 107 mm bottom bracket?

Frame Windsor - The Hour Hub Width - 120mm Stock Bottom Bracket Sizing - 68 x 103 mm Miche Bottom Bracket Sizing - 68 x 107 mm Miche Crank Set Requirements - 68 x 107 mm bottom bracket I'...
3
votes
2answers
1k 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 ...
2
votes
1answer
134 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
4answers
623 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 ...
4
votes
1answer
428 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 ...
5
votes
1answer
1k views

Are Shimano Hollowtech II bottom bracket spacers unique?

I'm moving my Shimano Hollowtech II XT crankset and bottom bracket over from a bike with 73mm bottom bracket to a 68mm bike. The only problem is that I only have 1 spacer and now I need 3 bottom ...
2
votes
2answers
479 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 ...
0
votes
2answers
237 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 ...
0
votes
1answer
311 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
141 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 ...
0
votes
2answers
86 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 ...
1
vote
1answer
375 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
707 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
votes
1answer
179 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 ...
0
votes
2answers
91 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 ...
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 ...