Bottom Bracket Problem

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Londoner_85

New Member
Hi all.

Images can be found here:
View: https://imgur.com/a/ZlqexTa

I'm hoping to get some help working out what went wrong here and how to avoid it happening again...
I made the (very bad) decision to upgrade my crankset and cranks a few months back and have had a bunch of issues since.
I think what has happened in the pictures is that I didn't tighten the bottom bracket enough so it started to 'undo' when riding which pushed it out into my chainring.. Which then chewed up the bottom bracket, but I'm not 100% sure. I was climbing hills on zwift at the time and it took me a while to realise pedalling was much more difficult then it should have been.
I'm intending on replacing it with Amazon product ASIN B0BPBHVSR9View: https://www.amazon.co.uk/RiToEasysports-Bracket-1-37x24T-Brackets-Aluminum/dp/B0BPBHVSR9
But wanted to check to see if my guess as to what went wrong is correct, or did I screw something up with the rebuild? And also check that is compatible?

Bonus issue: I've now tried 2 separate chainrings and both have had the same wobble - enough to always rub on one side of the derailleur. I now assume this is the attachment of the chainring to the crank? If so I might just disconnected the front derailleur.. I'd prefer to have these 155mm cranks over both chainrings.
 

Cycleops

Legendary Member
Location
Accra, Ghana
What make/model is the two piece crankset and BB?
 
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Ajax Bay

Guru
Location
East Devon
:welcome: Just get a proper Shimano H2 BB, like this:
https://www.chainreactioncycles.com/p/shimano-deore-bb52-hollowtech-ii-bottom-bracket

Specification of the super cheap and nasty BB linked in the OP:
Item Type: Bike BC Bottom Bracket
Material: Aluminum Alloy + Nylon
Product Size:
Length: Approx. 90mm / 3.5in
Outer Diameter: Approx. 44mm / 1.7in
Inner Diameter: Approx. 24mm / 0.9in
Thread Pitch: Approx. 35mm / 1.4in
Wheelbase: Used for 68-73mm / 2.7-2.9in Threaded Bottom Bracket
Features: Suitable for Use with Bottom Bracket Width of 68-73mm / 2.7-2.9in, Bearing Hollow Shaft, Sealed Bearing, CNC Turning, Anodized.
Suitable Models: Mountain Bike / Road Bike / Fixed GearBike / Folding Bike
 
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Punkawallah

Über Member
So to be clear, you had no problem with the chain ring catching the old front mech before you swapped the bottom bracket, but did have with the new bottom bracket?
 
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Londoner_85

New Member
No issue - I'll give more context.

The cranks are 'Goldix' from Aliexpress - the only place I managed to find 155mm cranks (I've since found some from Miche but they always appear to be out of stock). The bottom bracket was included - so unsurprising it isn't too good, although I did run it for a few months without issue before switching the 'Goldix' chain ring I bought with it to a DJC chain ring and DJC GXP adapter spider in an attempt to stop the chain ring wobble.

The BB is reverse threaded (tightens anti-clockwise), so I guess I might have loosened it when switching the chain ring and so it started undoing with the cranks turning? Which would have 'pushed' outwards into the chain ring adapter spider.
Is there anything else it could be?

If all I need to do is get a shimano BB then that's an easy fix. I'm just hoping I didn't do something else wrong!
 

Cycleops

Legendary Member
Location
Accra, Ghana
Could we also have a pic of the LH crank and pinch bolt. Might not be relevant anyway as I'll go on to explain.
I'd say your Ali Express crank was not working well with the included BB for whatever reason, maybe just because it's Ali E.
You can try a Shimano BB but it may not be made to same standards as your crank (compatibility). Only solution may be to get the crankset and BB from the same manufacturer.
 
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Peter Salt

Bittersweet
Location
Yorkshire, UK
If you're looking for good 155mm cranks - can't go wrong with Rotor Aldhu. It's hard to say what exactly went wrong with your £5 BB, I wouldn't overanalyze it. Get a slightly better one - like the Deore that got linked above.
 
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Londoner_85

New Member
Could we also have a pic of the LH crank and pinch bolt. Might not be relevant anyway as I'll go on to explain.
I'd say your Ali Express crank was not working well with the included BB for whatever reason, maybe just because it's Ali E.
You can try a Shimano BB but it may not be made to same standards as your crank (compatibility). Only solution may be to get the crankset and BB from the same manufacturer.
sure.
View: https://imgur.com/a/M1tGr7P


Get a slightly better one - like the Deore that got linked above.
Will do, thanks.
 

Cycleops

Legendary Member
Location
Accra, Ghana
Thanks. Looks just like a Shimano one but you don't know if it's made to the exact same specs.
You would be better off with a Deore as Peter says but then might be difficult to get your 155 length.
 

Ajax Bay

Guru
Location
East Devon
The spec I shared had a 24mm inner diameter which is what Shimano H2 cranks need. But as you imply "we don't know the specs". I assume these knock-off merchants have tried to make it so the cranks will fit an H2 BB when the useless one supplied fails.
155mm cranksets are scarce and expensive (unless cheap iyswim).
 
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