Clicks in the bottom bracket?

[JHZR2]

On both of my what I’d call thin wall aluminum bikes - my Scott Scale MTB and my Trek Verve 3, I get some clicking when I pedal. I thought on my mtb that maybe I cracked the frame. I’m pretty tall and on the upper end of what the typical bike design weight is (per my understanding). I’ve never seen any signs looking it over carefully.

As I’ve put the miles on my verve, I’ve started to get a click or cracking type sound when pedaling on it. I’m sure with the tagalong I typically have on it that we’re putting a lot of power down (we do try to ride fast), and a lot of weight.

I think I’ve traced that one to the bottom bracket and pedal assembly. I can consistently get a click/crack sound with the left pedal at the 10 o’clock position.

Is this common? Typical? I never encountered this with my Easton tubed prior mtb, or my Raleigh before that.

It’s the same sound on two different bikes from different manufacturers. It seems like maybe it’s just nature of the beast with these types of bikes that seem to have thinner wall tubing designed to be lighter.

Any suggestions? Could it also be that I’m just too heavy for the OE BB? I’m not that heavy but I am 6’4 and 250#, fairly muscular/athletic.

Thanks!

 

[wwillson]

I find that trying to figure out where a noise or click is coming from while riding can be almost impossible. While it could be the bottom bracket bearing, I doubt it is on a fairly new bike. If you put the bike on a stand and turn the crank, is it rough or does it have a catch? If you have to tools to remove and replace the bottom bracket, take the bearings out and see if they are rough.

[edit] That type of bottom bracket is really easy to remove with the correct tool. The "Do Not Disassemble" just means don't take the bearing out of the assembly. It's nice that they even show which way is tighten/loosen. It's about a 15 minute job. I'll give you a pointer, don't over tighten the bottom bracket when you put it back in, it just needs to be snug and that's it. Some people think they need to do the torque olympics on them and all it does is makes it really difficult to get off the next time and ruins the threads in the bottom bracket shell (the part welded to the frame).

I once had a click that no matter what I did, I couldn't get rid of it by working on the front end of the bike. That's where it sounded like it was coming from while I was riding. It took me months of riding and listening to this annoying click sound, to realize it was coming from the rear disk brake. A simple adjustment of the caliper and it went away. Made me feel silly chasing a sound and I wasn't even looking in the correct area

 

[fsdork]

Do you wear the same cycling shoes on both bikes? If so, it could be something in the shoe/cleat interface.

 

[JHZR2]

Do you wear the same cycling shoes on both bikes? If so, it could be something in the shoe/cleat interface.

No. Speed play frogs on my mtb, flat pedals on the trek.

 

[JHZR2]

It took quite a bit of force to do this by hand upside down, but I was able to make the clicks by getting the pedals vertical (as opposed to what seems to cause
It when riding), and flexing the assembly.

Of course someplace else in the frame may be flexing too.

 

[wwillson]

A video is worth a million words.

I would at least take the crank arms off and see if you can feel if the bearings are rough. Undo the clamp on the left crank arm and the right crank arm should pull out along with the spindle.

 

[MRC01]

Likely causes I've seen over the years

• pedal-shoe interface
  • already discussed
• pedal bearings
  • they spin at the same rate as the bottom bracket
• crank arm - bottom bracket interface
  • remove crank arms, grease the mating surfaces, reinstall
• bottom bracket bearing
  • remove the spindle, check for spindle wear at the bearing surfaces, bearing smoothness & free play, service/grease as needed and reinstall
  • Note: check bearings individually, and then check the spindle installed but without crankarms. Sometimes the bottom bracket sides aren't perfectly aligned in the frame, so the spindle might not spin smoothly & freely when installed, even if the bearings are fine. When this happens you'll usually see excessive wear on the spindle where it meets the bearings.
• cranks
  • Shimano crank arms (Ultegra & Dura Ace) are glued together and sometimes the glue fails
  • Look at the seams along the inside of the crank arms
• seat-seatpost interface
  • stress in the bottom bracket can transfer through the seat tube
  • remove the seatpost, grease and reinstall

 

[Number_35]

The external bearing assemblies are threaded oppositely (L side = RH thread, R (drive) side = LH thread) such that they shouldn't loosen with use ... but sometimes they do.

A loose one can result in a creaking or clicking noise when pedalling. You'll need a special tool to tighten them without scratching them.

After tightening I add matchmarks with a paint pen to see if the bearing assembly moves in future.

A clicking noise can be caused by the L crank not being tight enough on the axle. They used to say it was important to retighten the L crank arm after the first few miles of riding (not unlike checking lug nuts 50 miles after a tire change.)

 

[NYEngineer]

Yep. ^^ Exactly like 35 said. If mine start making noise, I disassemble, check everything for cleanliness and tightness and reassemble with fresh grease. Grease the BB threads where they go into the frame. Usually quiet after that.

 

[JHZR2]

So, I didn’t address this for a while. Between seasons, mainly short trips to baseball or the pool, etc, I’ve just lived with it. But it has gotten really bad.



I got the Park Tool to remove the crank bolt and the bottom bracket.

Everything feels fine bearing wise. Maybe one side is marginally tighter than the other, but both feel good and smooth.

I did notice this wear point:

It all looked ok:

The one side was much tighter than the other. When I pulled it, I saw a lot of aluminum.

I cleaned it up, but I wanted the park tool grease for this. Maybe John Deere polyurea is ok too??

Hoping when I get this greased up and together it will be quiet…

Thoughts on what to do next?

 

[ragtoplvr]

it looks like a crack on the left side between the 2 big holes.

Rod

 

[MRC01]

If this is the first time the BB has been removed, the Al shards could be from frame manufacture inside the tubing, eventually settling in the BB. Or they could also be threads that broke off, so inspect those threads. If you have compressed air, blast some through the frame tubes and see if more debris comes out into the bottom bracket.

The asymmetric wear marks on the crank spindle suggest the bottom bracket threaded cups on each side are not perfectly aligned in the frame. This puts the bearings at an angle, increasing friction and wearing them out faster. That's a manufacturing defect (poor tolerances), though many bikes do have this. It looks bad but not terrible, serviceable for an all around city bike.

If the bearings don't feel perfectly smooth, now is the time to replace them. Most likely, they need replacing.

Then clean everything up, grease the threads and the crank spindle where it goes through the bearings, assemble and torque it to spec. Then ensure the crank arms have no free play and check how freely (and quietly) they spin.

After that you should be good to go with no creaking.

 

[MRC01]

it looks like a crack on the left side between the 2 big holes.

It looks like a scratch to me (most likely harmless), but it's hard to tell from a photo.

 

[JHZR2]

It looks like a scratch to me (most likely harmless), but it's hard to tell from a photo.

I don’t think it’s a crack but I’ll have to look closer tomorrow.

If this is the first time the BB has been removed, the Al shards could be from frame manufacture inside the tubing, eventually settling in the BB. Or they could also be threads that broke off, so inspect those threads. If you have compressed air, blast some through the frame tubes and see if more debris comes out into the bottom bracket.

The asymmetric wear marks on the crank spindle suggest the bottom bracket threaded cups on each side are not perfectly aligned in the frame. This puts the bearings at an angle, increasing friction and wearing them out faster. That's a manufacturing defect (poor tolerances), though many bikes do have this. It looks bad but not terrible, serviceable for an all around city bike.

If the bearings don't feel perfectly smooth, now is the time to replace them. Most likely, they need replacing.

Then clean everything up, grease the threads and the crank spindle where it goes through the bearings, assemble and torque it to spec. Then ensure the crank arms have no free play and check how freely (and quietly) they spin.

After that you should be good to go with no creaking.

The bearings are perfectly smooth. One was slightly tighter than the other to turn, but it was tightened down in the threaded bracket much harder. I don’t think they will need to be replaced, unless an upgraded version will help with the misalignment and noise somehow.

 

[MRC01]

... The bearings are perfectly smooth. One was slightly tighter than the other to turn, but it was tightened down in the threaded bracket much harder. I don’t think they will need to be replaced, unless an upgraded version will help with the misalignment and noise somehow.

Upgraded bearings won't fix a frame misalignment. Sometimes bearings feel smooth but get rougher or tighter under load, and with all that loose debris floating around, there is a chance some of it got into bearings, so see how the cranks spin after you've put it all together. If they are tight and smooth, then you are good to go. And the creak will most likely be gone.
Good luck!

 

[Bottom_Feeder]

Interesting thread. I've noticed the cranks on my brand new, unridden aluminum-framed 26" GT Pro Series make a creaking click with every crank revolution which concerns me, but not anywhere near what you're experiencing.

 

[JHZR2]

Interesting thread. I've noticed the cranks on my brand new, unridden aluminum-framed 26" GT Pro Series make a creaking click with every crank revolution which concerns me, but not anywhere near what you're experiencing.

Well I’ll be lubing it up and checking it out tonight. I’ll post back when it’s done.

Knocking on wood!!

 

[Bottom_Feeder]

Hope that gets it sorted out for you. Good luck.

You're lucky you have a threaded bottom bracket which should make this easier.

 

[Nessism1]

It's common for creaking to develop after some period of hard riding, and sweating all over the bike. A good clean out, grease up, and reassembly typically solves the issues that I've experienced.

 

[Taildragger]

Shimano BBs are in-expensive. No big deal to just replace them. (usually under $30)