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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3answers
100 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
315 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
766 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
136 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
70 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
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. ...
12
votes
3answers
15k views

What are the benefits of external bottom brackets?

Pretty soon, I plan to replace the bottom bracket on my early 90's Sakae Litage road bike. It takes a standard, English-threaded bottom bracket. Right now I think it contains loose bearings--I was ...
0
votes
1answer
165 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 ...
4
votes
1answer
241 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
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 ...
5
votes
2answers
32k 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 ...
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vote
1answer
503 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
92 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 ...
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
76 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
546 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 ...
3
votes
1answer
328 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
385 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
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2answers
193 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
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1answer
259 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
140 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
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2answers
71 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
326 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
641 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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1answer
151 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
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 ...
1
vote
1answer
196 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
votes
1answer
49 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
votes
3answers
359 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
votes
1answer
771 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, ...
-1
votes
1answer
155 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
votes
1answer
241 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. ...
1
vote
1answer
73 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
votes
2answers
999 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 ...
1
vote
2answers
239 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 ...
0
votes
1answer
944 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, ...
3
votes
2answers
167 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 ...
3
votes
2answers
2k views

how many spacers do I need for a 83mm bottom bracket and a 142x10 hub?

I have a Zee crankset on a 83mm bottom bracket (downhill bike). The Shimano manual says to use two 2.5mm spacers on the drive side, and one 2.5mm spacer on the non-drive side. However, this presumes ...
1
vote
1answer
208 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?
1
vote
2answers
431 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. ...
1
vote
2answers
195 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 ...
2
votes
1answer
196 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 ...
3
votes
1answer
3k 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
228 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 ...
2
votes
2answers
3k 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 ...
0
votes
2answers
95 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
2
votes
2answers
186 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 ...