Arrrrgggh...bottom brackets

[AustinBike]

My urban singlespeed is making a ton of noise, creaking, popping, etc. It's a steel frame so it should not be making this much noise. I have replaced:

• Front cog
• Rear cog
• Chain

So at this point there are only 2 places left, the bottom bracket and the rear hub.

Here is what I am hearing:

 

Here is the amount of play in the rear hub:

 

So the question is do you think this is a hub or bottom bracket noise? To me it feels like BB.

Now the BB problem.

I have an FSA Comet (~2014) crankset. I bought a Shimano BB which *should* fit, but I could not get the spindle through the BB, nor could I get it through a SRAM GXP BB. The spindle is supposed to be 24mm but is seems to be just slightly larger, I can get the spindle into the bottom bracket cup but I can't get the spindle to continue through.

The current bottom Bracket is a RaceFace X-type BB which claims "Interchangeable with select Shimano and FSA external mountain BB systems."

So what gives? I have 2 BBs that I can't seem to use and a crank that is just barely too big. From 24mm the next step up is like 28mm or so. This seems to be ~25mm or so, just barely larger.

All advice is appreciated.

 

 

[mack_turtle]

My CX bike came with a FSA crankset. The BB crapped out on me almost immediately so I replaced it with a Shimano BB. It was a tight fit but it went in with a little encouragement from a rubber mallet. I later replaced the crap FSA cranks with an older Shimano 105 set.

Might be a good idea to get your BB shell faced. If the frame/cup interface is a little off or slightly too wide due to paint or shoddy manufacturing, that could lead to premature bearing death.

GXP design uses a non-drive side bearing with a significantly smaller inner diameter. The spindle on a SRAM/Truvativ crank has a step-down shelf where that bearing rests. It basically eliminates the possibility of killing the bearings by over-preloading the bearing, but allows enough movement that the drive side bearing on those tends to die earlier. So yeah, a straight 24mm spindle should not fit in a GXP bottom bracket. 

Edited December 14, 2019 by mack_turtle

[mack_turtle]

I'd just tear down the drivetrain and start again. Check everything with a torque wrench:

Chainring bolts, pedals, BB cups, crank fixing bolts, etc. Have you ridden it in the rain lately? Moisture can get into the books and crannies and cause that stuff.

Sometimes a dry seat tube/ seatpost can creak, along with under-torqued seatpost guys.

[AustinBike]

The problem with the BB is not the facing, I never even tried to put it in the bike. I took the end cap and tried to put it on the spindle, no go. It fit in to about a half inch or so, to the end of the (?) flanges on the spindle, then stopped. 

Definitely not the seat tube because when I stand and pedal I can get the clacking sound.

[AntonioGG]

That rear hub has too much play.

When you hear that clicking sound, are you pushing hard on it?  I couldn't tell for sure from the video, but it seems like it doesn't happen with every crank revolution.  If you hadn't said you've changed cog, ring, and chain, I would have thought some kind of chain issue.

I'm recovering from a cold, otherwise I'd say bring it over to my house and we can take a look at the bike.

[AustinBike]

This was about as far as I could get it in. Then Jonathan’s comment about a rubber mallet put me in the position of installing the BB and giving it a few healthy whacks. Bingo. It eventually worked itself in. Quick round in the neighborhood was quiet but it usually takes a few miles before the clacking begins. Tomorrow’s jingle bell ride should tell me whether it was the BB or whether we are down to the final piece. At that point I will drop it on a shop because I could not get the rear hub disassembled with cone wrenches so I will let a pro do it. 

[mack_turtle]

I've dealt with hubs like that before. I could probably pop it open for ya. Might have a fried sealed bearing. Hard to find parts for those!

[AustinBike]

That is why a shop is appealing. If I take it to them it is their problem. And if the hub is toast and I need a new one, I don’t have to mess with it. Tomorrow I should know for sure. 

[Teamsloan]

According to what I’ve read, FSA cranks use their own BB which is “supposed” to work with Shimano BB’s but really it’s a hair different. Their tolerances are not as good as Shimano’s though, so some fit and some don’t. The fact that you got yours to fit is great but the BB may not last as long. Either get the FSA bb or ditch the crankset.



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[AustinBike]

Yeah, this is my urban commuter bike so, while I put significantly more miles on this than any of my other bikes, I don't want to sink a lot of money into it.

The $14 Shimano BB is working for now. The next BB will be an FSA. Long term I may ditch the cranks altogether, but the bike *might* have a couple of cranks in the frame that would necessitate a Kona warranty replacement, so I'd really wait until that time before I headed down the path of putting more money into the bike. For $450 (used) it has been a hell of a workhorse.