View Single Post
  #8  
Old February 15th 19, 08:06 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 1,261
Default Tracking Down BB Noise

On Friday, February 15, 2019 at 9:38:00 AM UTC-8, jbeattie wrote:
On Sunday, February 10, 2019 at 7:57:28 AM UTC-8, AMuzi wrote:
On 2/9/2019 6:34 PM, jbeattie wrote:
Rule of thumb -- when you have a BB noise, start with the rear axle drop-out interface. I ignored the rule of thumb trying to track down what was clearly (in my mind) a BB problem -- a light thunk every time the left pedal arm hit the bottom of the stroke. This was on my Synapse with an OE Cannondale SI crank -- a pretty simple crank with a SRAM-like interface (bolt on arm and not pinch bolts like Shimano). So, I get out my jumbo 10mm hex socket to remove the bolt/cap, pull of the crank with a kludged Park remover (long story), check the bearings -- and they're fine. Grease everything up, re-assemble, go for a test ride in the snow, and it's still thunking. I get off the bike, rock the crank, and I can produce the same thunking -- but I don't really feel play in the crank, but I figure its moving laterally and needs another shim. Pull the crank again and put in a .5mm shim. Still thunking. Back onto the stand. The bike has a 12mm through axle rear hub (HED), which I had tighten

ed earlier to rule out any issue there, but what I didn't notice is that the hub axle end cap had come loose, which allowed the hub to move laterally. Pull out the cone wrenches, tightened it up and thunking went away. A five minute repair. I don't know how or why the end cap loosened, but I've had the same problem on other wheels with similar thread-on end caps.

-- Jay Beattie.


+1
Not just through-axle.
Dry QR cams make the same noise because you think the wheel
is secured but it's not.


My commuter was making a ton of racket yesterday -- BB noise like I was rocking in a bamboo rocking chair. I reset the QR on the rear wheel and oiled the chain, and it all went away. A dry chain can make a lot of noise, too.. With all the rain, the lubricant gets flushed off my chain pretty quickly.

-- Jay Beattie.


According to Zen you're too stupid to ride a bike if your chain starts making noise.

According to me the weather changes mean that you have to find the correct lube for the weather. I have an entire shelf full of different lubes and they all react differently to weather. Rock and Roll doesn't work in the cold and the Ice Wax does.
Ads
 

Home - Home - Home - Home - Home