Questions tagged [bottom-bracket]
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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Why are road-bike freewheel ratchets so loud?
(This is related to this question here, but while that one is focusing on quality of the gear (higher end vs lower end), my question focuses on the style of the bike.)
I have made the experience that ...
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Keeping the actual bottom bracket/crankset while increasing the chainring size
On my bike, I currently have a 50 x 34 crankset:
I would like to mount bigger chainrings: I was thinking about a 53 (or a 52 at least) as the bigger one.
I see that my BB has "36 x 24" ...
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How to fix a bottom bracket shell that has been cut from outside?
I have a 27.5" MTB which has a damaged bottom bracket shell. When I install the bottom bracket into the shell, it does not stay in the center of the shell. It leans towards the bottom of the ...
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Bottom bracket: What to do about rust in cup + blemish on spindle?
My partner and I are repacking a bottom bracket on a Dawes Londoner. It's our first time doing something like this, and we've noticed a couple of imperfections we're unsure about (see below). Are ...
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Bottom bracket sliding
I was playing basketball, airballed, the ball landed on my frame and the bottom bracket slid out like shown in picture, any way to fix this myself? Does not go in by force. Thank you in advance.
!(...
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Creaky sound while pedaling
After some rainy rides my bike developed this creaky sound.
https://youtube.com/shorts/w0bhjAHORoU
I took mine SRAM Red PF30 bottom bracket apart, cleaned up the bearings. I have ultrasonic machine so ...
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What properties to look for in a bottom bracket to survive winter use on a road bike
My road bike bottom bracket which has seen some roughly 6000km and one winter with lots of wet and salty roads and some freezing has developed some noticeable play now. It's still running smoothly and ...
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How to read chainline specs for crankset and bottom bracket compatibility?
General question:
I've been trying to find a replacement crankset, but have been having trouble understanding other posts about compatibility with respect to chainline. It seems that people add the ...
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Will Sram Dub Pressfit BB92 fit a Sram Apex Crankset?
I would love your help. Will this Sram Dub Pressfit BB92:
Fit the Sram Apex Crankset:
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1
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Bottom bracket sizing: Samox, SRAM, and Shimano confusion
I have a difficult time finding the right sizes. I bought a Canyon, with these original parts:
Bottom bracket: SAMOX Pressfit BB8601
Crank: SAMOX TAM37 46T
With a SRAM apex gearset, SRAM PG-1130 ...
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crank arm with 15mm diamond holes
I have a stationary bike that was given to me. The threads for the pedals are stripped, so I was trying to replace the crank arms.
Both arms are diamond hole types, I managed to get them off, but I ...
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How bad is an internal bottom bracket with a body that is 2mm longer than the orignal BB
My belt drive bicycle came with a Shimano internal bottom bracket. Shimano BB UN300, 127 mm length, 68 mm width, square taper. Below a picture. On the part is written
BB UN300
68 UJ
BC137x24D-EL
I ...
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Is the Shimano Bottom Bracket UN300 D-EL 127mm or 127.5mm?
I have this bottom bracket on my belt drive bicycle.
Shimano UN300 68 UJ BC137x24 D-EL
The person who sold me the bike said the BB's length is 127mm, width 68mm, and square type. (I cannot get hold ...
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"Vintage" internal cable routing to external
I have an "old" bicycle. The branding on the frame suggests it's a "Coppi", and I believe it to be from the 80s.
There's a lot that I don't know about the bike, but for the ...
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JIS or ISO standard on Merlin Road 92 Titanium bottom bracket spindle?
My early 90s Merlin road frame got that titanium spindle and I wonder whether it is JIS or ISO square tapered. According to the catalogue the name of the bottom bracket is "Beta-C"
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What is the difference between Shimano SM-BBR60 and Shimano BB-MT501
Are these 2 bottom brackets compatible? Is one 'better' than the other? Is one more durable than the other, more efficient than the other?
I would guess that the BB-MT501 is meant for dirtier ...
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Left side crank arm stuck to spindle due to stripped threads, how to remove bottom bracket
The bicycle in question is a "Schwinn Women's Ranger 26" Mountain Bike". It has a slight play in the crank arms, stemming from the bottom bracket.
I tried taking the crank arms off, and ...
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Are 68mm and 73mm bottom bracket left side cups identical?
My MTB has a 73mm bottom bracket shell but it had 68mm BB installed. I found and purchased a Shimano BB-ES300 73mm BB but unfortunately I had to break apart its plastic cup (left side) since I ...
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FSA B3155 bottom bracket compatible replacement
I have Orbea orca m35i with Shimano cranks (24mm).
During bottom bracket bearings replacement, the cup got damaged.
It says "FSA B3155" on the cup, FSA support said this would be a ...
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bottom bracket axle length, chainline and crank compatibility
TLDR: How much leeway there is, if any, in selecting the bottom bracket axle length for octalink or square taper cranks in order to reduce chainline?
Background: I'm doing some minor modifications to ...
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FSA Mega Exo 24 threaded shell BB turns free when off the bike, but turns rough and gritty once installed
My FSA Mega Exo BB is about 2 years old and came on the bike when I bought it new. The right-side bearing is fine. However, the left-side bearing is gritty and resistant when installed in the frame, ...
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New Bottom Bracket grinding/crunching?
I recently bought a new Shimano BB-MT501 bottom bracket and installed it. However, once I put the Hollowtech crankset back in place, when turning the pedals there is a very obvious grinding or ...
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Is it correct that the bottom bracket shell thread does not go all the way around?
On the inside of the bottom bracket shell, the thread does not go all the way around. At the places where the tubes are welded (or attached) into the bottom bracket shell, there are holes in the ...
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How to replace internal BB with external BB on belt drive bike?
My Rohloff touring bike has an internal bottom bracket (BB). I would like to replace this with an external BB.
Current components
Front Sprocket: Gates Carbon Drive, CDX, 4 bolt 104mm BCD, 50 teeth
...
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What is this bottom bracket tool called?
I came across this tool on Amazon India, to remove the bottom bracket.
I don't know what this tool is called.
I've seen similar tools at motor workshops, so I'm assuming it is a common tool and not ...
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Silverback Bottom Bracket Replacement
I have removed the bottom bracket from my bike as it was very wobbly. I am trying to teach myself about these things and I am making progress however the bottom bracket looks weird. Granted I have not ...
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Bottom bracket not centered in BB shell
I removed my bottom bracket because there was creaking sound while I was pedaling. Cleaned it and wanted to reinstall but the crank in the middle was hardly turning when I fully tightened the cups on ...
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Bike pedaling makes cracking noise under middle or high load
Can this be related to bottom bracket bearings of Race Face BB92, PressFit? The chain is freshly lubricated and quite a new one. No noice is produced when pedalling with low load or not pedalling.
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Bottom bracket confusion
I have a 2016 Merida Big Seven 100 27,5" XC MTB which I bought from second hand market. It came with a 68mm cartridge style BB. However I found out that this bike has originally 73mm BB. What ...
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Bottom bracket BSA, 68mm vs. 73mm
I have the bottom bracket shown below, that needs replacement.
The bike is from 2014.
I live in Argentina, and here I see plenty of 113mm x 68mm in the market. But I cannot get a 113mm x 73mm as the ...
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Bottom bracket BSA, brand question
EDIT: I have removed the part of the question about the size and moved it elsewhere, as it is the most important part as of now.
I have a bottom bracket that needs replacement (or repair?).
The bike ...
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Square-taper crank wobble/movement in only one spot
For square-taper aluminum cranks:
When my drive-side crank is in the 12:00/highest position and the non-drive side in the 6:00/lowest position, there is slight play between both cranks (it rotates ...
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internal routing and bottom bracket sleeve
I was wondering regarding the sleeve that comes with the bottom bracket I got from chris king.
My frame has internal routing, that I believe entails that cables should go through the bottom bracket. ...
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front chainline adjustments for 42.5 rear chainline
I have a 42.5 rear chainline (12 speed sram eagle).
In the front, I purchased a eewings-mountain crank.
According to the docs, the offset is (55-chainringoffset).
If I get a 6mm offset chain ring, it ...
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Guess the erased text on this bottom bracket
I'm trying to keep my old mountain-bike alive, it's been so good to me. I acquired the proper tools to remove the crank and, well I guess I have two questions:
There was a lot of rust and water in ...
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Installing crank on threadfit30
I wanted to get advice regarding installation of new bottom bracket and crank.
My frame BB shell is BSA68.
Bottom bracket is threadfit 30
crank is eewings mountain (which expects a BSA73).
I looked ...
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Will this combination of crankset work?
My frame specification for bottom bracket is BSA 68mm.
Would the following bottom bracket and crankset fit together?
cane creek eeWings Mountain (link)
Chris king threadfit 30 bottom bracket (link)
...
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BB386 bottom bracket - Is this kind of bearing wear normal?
I had my carbon road bike at service and the BB bearings (again) needed replacing, according to the mechanic, the drive-side one was hardly spinning and the other one also pretty much done with. Can't ...
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Bottom bracket differences
what is the benefit of a more expensive bottom bracket? I just purchased a used Cube Agree C:62 (previous version of https://www.cube.eu/.../d3c24ded01f0b52c27caca216a293153...) without a bottom ...
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I have a Triban RC100 (Women's bike, small) what size bottom bracket does it have?
I recently crashed my bike and bent the stock crankset so I am thinking of buying a new one and replacing it but for that I need to know what size bottom bracket comes with a stock Triban RC 100 women'...
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How can I measure whether pedals and bottom bracket are properly aligned to each other and parallel?
I get a weird sensation on the left pedal when I'm riding one of my bikes, as if the pedal was not perpendicular to the crank arm. It feels like the pedal is moving under my foot, although there is no ...
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Replacement for VP-BC73E Bottom Bracket
I cannot find my bottom bracket online anywhere. It's called "VP-BC73E ". However, I can find loads of "VP-BC73" (E is missing). Would it still fit/work?
I found this information ...
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Tiny dent near the bottom bracket of a new hardtail - should I be concerned?
I’ve just purchased a new Trek Roscoe 7 (aluminum hardtail mountain bike) recently and I’ve noticed this tiny little dent today. It is on the drive-side chainstay near the bottom bracket.
Should I ...
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2018 Diamondback bottom bracket size
Does anyone know what size a 2018 Diamondback Line bottom bracket is?
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Can someone please give some advice to help find a new crankset?
I apologize in advance if I mix-up some lingo, I have almost no experience in fixing bicycle drivetrain.
Previously I had Comet CKM-7159 as crankset (I managed to find this datasheet that seem to ...
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How to remove and replace wire pins from axle?
I have a Kent adult tricycle. It has a band brake attached to the rear axle. The brake pad is old and no longer grips, so I need to replace it. Apparently I can't just replace the pad because it is ...
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Should I use fiber grip or grease when installing a bottom bracket into a carbon frame?
I am assembling my first carbon road bike and came across a question regarding on how to install the bottom bracket. I decided to go for this Ninja BBRight for my Cervelo Caledonia.
The Token's ...
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Noisy bottom bracket SHIMANO BB-RS500
About a year ago I've got this Stevens Supreme fitted with Shimano Tiagra BB-RS500 bottom bracket.
In less than 2 months it started clicking and screeching loudly which only had gotten worse over time....
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How can I know if I need spacers for my bottom bracket / crank?
I am assembling a bike on my own and came a cross the topic spacers for bottom bracket/crank.
I am installing a Shimano FC-R7100 crank with the bottom bracket model SM-BBR60.
By taking a look at the ...
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Another very stuck bottom-bracket – non-standard size (37 mm flats)
my name is Alex and I’m new here. I’m a bit of an amateur but I’ve decided to attempt the modernization of an old French Liberia racer from 1978. The aim is to create a bike I can use as a daily ...
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