Posterous dies on 4/30/2013 so I've moved all my content and switched to Blogger.

Friday, March 23, 2012

Noisy Creaky Creaking Bike - Rule These Out Before Blaming Your Bottom Bracket

Her Diary:

Tonight, I thought my husband was acting weird. We had made plans to meet at a nice restaurant for dinner. I was shopping with my friends all day long, so I thought he was upset at the fact that I was a bit late, but he made no comment on it. Conversation wasn’t flowing, so I suggested that we go somewhere quiet so we could talk. He agreed, but he didn’t say much. I asked him what was wrong; He said, “Nothing I asked him if it was my fault that he was upset. He said he wasn’t upset, that it had nothing to do with me, and not to worry about it.  On the way home, I told him that I loved him. He smailed slightly, and kept driving. I can’t explain his behaviour – I don’t know why he didn’t say, “I love you, too.” When we got home, I felt as I had lost him completely, as if he wanted nothing to do with me anymore. He just sat there quietly, and watched TV. He continued to seem distant and absent. Finally, with silence all around us, I decided to go to bed.About 15 minutes later, he came to bed. But I still felt that he was distracted, and his thoughts were somewhere else. He fell asleep – I cried.  I don’t know what to do. I’m almost sure that his thought are with someone else.  My life is a disaster.

His Diary:

There's this creaking on my bike that sounds like it's coming from the bottom bracket … can’t figure out why.


Well, that creaking could be many things.  Everybody wants to blame the bottom bracket first but there's many easier things to address that need to be ruled out before going thru the trouble of removing a crank and BB.  Here's my rank of list of common to uncommon.  I betcha a dollar it's the chainring bolts.
  • Chain ring bolts...the bolts are truly all
    tight, right?--like not just both halves of the chainring-bolt spinnng around
    together when you turned the wrench?
    • Seat post/frame needs grease 
    • Seat rails need grease
  • Loose spokes nipples check rear first then front...
    if it only creaks when out of the saddle that's a smoking gun for front spoke tension too lose.  You can pluck the spokes like your playing guitar and they should all "Plink"  if you hear any "Plunks" o "Donks" or if they are all Plunks/Donks then tighten that shit up...start at the valve stem and give 1/4 turn to each spoke all the way round (tell family and friends to F off if they try to interupt you while you are making your way around the wheel.  Repeat until tension feels right..."Plinks" not "plunks" and heaven forbid "Donks".
  • Cracked frame - Here's a test to see if it's the frame.  Stand on the left side of the
    bike.  Put the left pedal at 6:00.  Hold the seat and handlebar and
    lean the bike away from you.  Put a foot on the pedal's end and push the crank arm  toward the center line of the bike and the floor. This flexes the frame.
    Pump it a few times with your foot and  Listen for creaks.  Repeat on
    right side.
    • Right crank arm to the spindle may be the problem area that needs lubed but ifyou go that far you may as well pull the whole crank out and grease the shit out of the spindle and splines (check for cracks in the splined part of the spindle) 
    • While you're here you may want to pull the bottom bracket cups out too.  Lube and teflon tape onthe BB shell threads should also help. 
    • Crank arm to the BB may be the problem area that needs lubed but if you go that far you may as well pull both crank arms and BB.  And reinstall everything with a shitload of grease .  You'll need a crank puller and bb removal socket.  Lube and teflon tape on the BB shell threads should also help.
Other things to consider
-Under load only, huh?
Maybe BB maybe not.  Probably chain ring bolts.
-Once or twice per revolution (certain place(s) in pedal stroke where it happens)?  Maybe BB maybe not.  Probably chain ring bolts.
-Does it make racket when seated or standing or both?   
 If it always makes noise just take it all apart and rebuild for good measure.
-Does it make racket uphill or downhill or both?
 If it always makes noise just take it all apart and rebuild for good measure.
-Pull the chain off and coast it around.  
Still noisy if you pedal round and round?  Then BB and/or cranks suspect.
Fixed Gear??? My 1st bet-Cog sharkfinned or burred?  Literally, the teeth look like sharkfins or have visible burrs.  That was my culprit for noisiness last spring.  Replace it anyway...get a good one like surly, shimano, soma, eurasia...don't spend < $20 and get a POS stamped ring cause it'll strip your hub's threads.



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