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.)

Filter by
Sorted by
Tagged with
3 votes
1 answer
85 views

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 ...
AhseemHermanson's user avatar
7 votes
2 answers
1k views

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 ...
Mellow Monk's user avatar
4 votes
1 answer
71 views

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 ...
James Burton-Durham's user avatar
5 votes
3 answers
290 views

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 ...
Ender's user avatar
  • 1,514
1 vote
1 answer
79 views

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. ...
petrsyn's user avatar
  • 143
1 vote
2 answers
80 views

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 ...
Ender's user avatar
  • 1,514
3 votes
2 answers
141 views

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 ...
sancho.s ReinstateMonicaCellio's user avatar
4 votes
1 answer
109 views

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 ...
sancho.s ReinstateMonicaCellio's user avatar
2 votes
1 answer
54 views

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 ...
Laoshi's user avatar
  • 739
2 votes
1 answer
123 views

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. ...
yuvalon's user avatar
  • 491
0 votes
2 answers
130 views

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 ...
yuvalon's user avatar
  • 491
4 votes
2 answers
574 views

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 ...
Morten Nørgaard's user avatar
2 votes
1 answer
48 views

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 ...
yuvalon's user avatar
  • 491
3 votes
1 answer
142 views

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) ...
yuvalon's user avatar
  • 491
4 votes
1 answer
182 views

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 ...
DoNuT's user avatar
  • 4,186
3 votes
1 answer
182 views

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 ...
user2912328's user avatar
1 vote
1 answer
129 views

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'...
einstein dhayal's user avatar
4 votes
4 answers
660 views

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 ...
Robert's user avatar
  • 2,051
1 vote
1 answer
62 views

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 ...
James's user avatar
  • 13
0 votes
1 answer
177 views

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 ...
TommyYOyoyo's user avatar
0 votes
1 answer
178 views

2018 Diamondback bottom bracket size

Does anyone know what size a 2018 Diamondback Line bottom bracket is?
Sam44's user avatar
  • 1
1 vote
1 answer
72 views

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 ...
kazaker's user avatar
  • 13
4 votes
1 answer
382 views

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 ...
causative's user avatar
  • 143
3 votes
1 answer
426 views

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 ...
Bob's user avatar
  • 292
6 votes
1 answer
532 views

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....
Petr Gladkikh's user avatar
3 votes
1 answer
2k views

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 ...
Bob's user avatar
  • 292
8 votes
2 answers
192 views

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 ...
TooMuchCoffeeMan's user avatar
2 votes
2 answers
531 views

Which tool to remove this bottom bracket nut - photo provided

I have an Apollo Transfer 21 inch frame and need to remove the bottom bracket. It seems to be a screw in bottom bracket. I am new to bicycle maintenance by the way. I tried a 26mm spanner to remove ...
Angus Comber's user avatar
0 votes
1 answer
55 views

Trek crossrip ltd 2015 bottom bracket model

Hello I have a Trek Crossrip ltd 2015 gravel bike. The frame is alpha aluminium 100 series and the bottom bracket is Hollowtech II. What bottom bracket should I replace it with?
Harri Juus's user avatar
2 votes
1 answer
121 views

Shimano BB: add grease over threadlock?

The dealer manual for the Shimano BBR60 bottom bracket says to grease the threads of the cups before inserting. But I noticed that the threads have some kind of grey threadlock compound applied to ...
someguyinafloppyhat's user avatar
2 votes
1 answer
197 views

1 piece to 3 piece crank conversion

I wish to convert my 1 piece crank to a 3 piece crank. I have a conversion kit that presses into the bb shell and accepts a cartridge style bb. I went to order one and realized I have no idea what ...
Raymond Dunne's user avatar
0 votes
0 answers
56 views

Damaged carbon fibre [duplicate]

My chain dropped and got stuck in my bottom bracket while I was going uphill. I think the force from the pedal stroke damaged the carbon fibre. Wondering what is recommended when something like this ...
Jocelyn's user avatar
0 votes
0 answers
53 views

What is the correct BB spindle length for Kooka cranks?

Does anyone know the correct square taper bottom bracket spindle length for an early 90s Kooka triple mountain bike crankset?
Noah Sutherland's user avatar
3 votes
2 answers
106 views

BB snapped and stuck inside shell of euro threaded frame?

I was in the process of prepping to install a new BB on my bike when I noticed this remnant that I believe might be part of my old BB. To my novice eyes, it looks like something snapped and is now ...
Terry T's user avatar
  • 85
1 vote
1 answer
252 views

Which mid drive motors use the same frame interface?

One concern with mid drive e-bikes is that if the motor breaks in ten years, probably there is no exact replacement available. But do the manufacturers keep the same interface for their different ...
Nobody's user avatar
  • 1,780
4 votes
1 answer
168 views

Bottom bracket has play. Can I still tighten this, or do I have to replace it/fix it properly? Tools? (incl. videos and photos)

I'm staying with a relative and borrowed her bike for a ride. It now has play on the bottom bracket - as shown in videos below. TL;DR Is it possible to judge if I can still just tighten this, or do I ...
pateksan's user avatar
  • 2,304
3 votes
1 answer
79 views

Frame and bottom bracket compatibility

I have problems with adjusting front shifting on my MTB so I suspect something is wrong elsewhere. This is a 27.5" Merida Big Nine 100 XC MTB. Its chainset has been replaced with a Shimano FC-...
Ender's user avatar
  • 1,514
3 votes
0 answers
74 views

Request for clarification of bottom bracket threading

I know that bottom brackets have a left-hand thread on the right side, and a right-hand thread on the left side. But I fail to understand why. I would have thought it should be the other way round, to ...
Burki's user avatar
  • 1,248
2 votes
1 answer
86 views

BB/Cranset creaking on/off

I'm having an issue with a creaking sound on a brand new bike (see video below). It seems to happen after 30+ min rides, you can faintly hear it when the pedals are spun backwards but this usually ...
Jordan's user avatar
  • 21
6 votes
1 answer
182 views

Small metal pellets in a new frame

I am working on assembling a new boxed bike (aluminum Kona Libre), starting by tearing it completely down and making sure all components are properly installed, greased and adjusted. The headset felt ...
djwicket's user avatar
2 votes
0 answers
180 views

Headset and BB compatibility Kona Rove LTD 2019

I've got a Kona Rove LTD 2019 and it's about time to change bearings. This is the exact model : https://99spokes.com/en-EU/bikes/kona/2019/rove-ltd I'd like to change headset and BB because they're ...
Florian F.'s user avatar
5 votes
4 answers
1k views

BB drop vs BB height from stability perspective

While I have heard that a lower bottom bracket tends to give more stability, I'm confused as from which point of reference yields such an effect, from the wheel axle (BB drop) or from the tire contact ...
Gregory Leo's user avatar
  • 1,295
4 votes
1 answer
247 views

BB386 bottom bracket - clicking noise once per rotation

I've been posting quite some videos about defects on my bike her recently, so I seem to be a winning streak. On my last ride, a strange noise started to occur on my bike. Might be that it was ...
DoNuT's user avatar
  • 4,186
5 votes
2 answers
296 views

Threadlock for Bottom bracket on Titanium Frame?

I'm looking into installing a bottom bracket for my titanium bike frame. The bottom bracket that I purchased (SHIMANO ULTEGRA Threaded Bottom Bracket 68/70 mm shell width) seems to have some kind of ...
user1301593's user avatar
1 vote
2 answers
61 views

Front chain rings don't shift properly after installing a bottom bracket and shorter spindles

My problem is I fitted shorter spindles and a new bottom bracket now front gears are not working as they should, the chain on the third click should be on the outer sprocket but only goes to the ...
jim cooper's user avatar
1 vote
0 answers
43 views

Replacement BB chainline check?

I want to replace a bottom bracket (to add a torque sensor for a recent ebike conversion). Current BB spindle length is about* 114mm, replacement is 127mm. So, all else equal, we're talking about ...
bike_tourist's user avatar
6 votes
3 answers
702 views

Broken plastic HollowTech II BB spacers, why?

Yesterday I was installing a BB-MT501 HollowTech II bottom bracket into my ~2006 Trek 520 frame. This frame has a 68mm BB shell. I was following the directions on Shimano's website: https://si.shimano....
Dan's user avatar
  • 193
1 vote
1 answer
216 views

Crankset compatibility, old 105 SC to new Claris FC-RS200

My bike currently has an old 105 crankset. It's a 105 SC, from 1989. The rest of the components are Claris R2000. I'd like to replace the crankset with a new one with smaller rings. I thought of the ...
elcye's user avatar
  • 11
-2 votes
4 answers
218 views

Confidence in carbon bike frame after sealed bearing replacement

You buy a new bike. The bottom bracket makes a funny noise and needs replacing. For many other product categories (computer with a noisy fan, ...), you'd worry you had a lemon on your hand. It would ...
Sam7919's user avatar
  • 9,092
5 votes
1 answer
124 views

What is this type of bottom bracket and is it serviceable?

I encountered an old and beat up bike today with the bottom bracket pictured below. I could feel play in the bearings but did not see any lock ring or adjustable cup. The 14 mm bolt of each crank arm ...
olliebulle's user avatar
  • 4,141

1
2 3 4 5
14