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Discussion Starter · #1 ·
I realize there are quite a few of these threads and it's not the easiest problem to diagnose and solve, but I want to see if anyone has any ideas for a possible fix.

For the past couple years my bike has made a sort of creak/click noise from what sounds to me like the left crank arm area. I am trying to deal with it now because I'm starting to ride more seriously and more often. By the way, I ride a 2005 Trek 6500. I use platform pedals.

The noise occurs when pedaling hard, but only when the left crank arm is leading, or forward. I can also produce the noise without pedaling, by having the pedals horizontal and bouncing on them with more weight on the left one.

It is not a constant thing. What I mean is if I bounce on the horizontal pedals once with the left pedal forward, the noise will occur, but won't occur again until I rotate the pedals so the right one is in front and bounce again.

It's sort of the same when pedaling. The first few hard pedals will produce the noise but it won't happen again until I take the weight off of the pedal and re-apply weight again. I have taken the seat post out so it is not that. I have swapped in 3 different pedals as well and still the same noise. I have tightened every bolt I could.

I tried the bouncing thing without pedals installed by just putting weight on the crank arms and noticed that the noise is a lot harder to produce, but it still happens. Possibly because I have less leverage to put my weight on?

My LBS installed a new fork for me today and I told them about the problem but the mechanic said he couldn't reproduce the noise on the stand so he didn't fix anything.

What should I do? I don't have the tools or experience to take the bottom bracket apart. Should I just bring it back to the bike shop and ask them to dissassemble everything down there to clean and grease it?
Sorry for the long post. I appreciate any help or advice you can give me!
 

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i have almost the exact same problem as you. mine seems to have gotten a little worse over time. I'm going to be watching this thread closely. Now bestow upon us your superior knowledge, oh great MTBR forum kings!
 

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Probably the bottom bracket. The one that comes with the bike may only last a year if you ride a lot and/or get it wet.
 

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Discussion Starter · #4 ·
Haha it's good to know I'm not the only one with the problem!

Hmm. Would I be better off buying one online and asking my LBS to install it? I have no idea what type or size to buy. Also, should I just jump right in to buying a new BB? I mean I don't know what else it could be, and there isn't really anything else I can think to do since I don't really know anything about taking it apart or greasing it.
 

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I had the same issue, creak on both sides, but needed to alternate pressure to get creak to repeat.
Removed cranks, and found BB was bad, (turned and felt like sand was in there, very rough). Went to Jensonusa for a BB and purchase whole crank BB set-up. Installed myself and took it for a test ride.
Creak, creak, creek, same... hmmm
I knew the BB was bad, so I have new cranks and same creak.
I ride a Giant Anthem, FS. I thought maybe the linkage,
Played with it a little more, now Im thinking may the front end creaks,
headset/ forks ?
 

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My guess is that the creak is coming from either the left BB cup or the interface between the left crank arm and the BB spindle.

In either case, the fix is simple, provided you have the necessary tools. I would suggest investing in these tools. You will need to figure out what kind of bottom bracket and crankset you have. The Trek web site indicates that the 6500 has Shimano Octalink BB w/ compatible crankset. If that's the case for your 2005 version of the bike, and it could well be, you'll need a crank puller, such as the Park Tool CWP-7, and a bottom bracket tool, such as the Park Tool BBT-22 or Park Tool BBT-32.

Follow the crank removal and installation instructions for removing one or both cranks. You can probably get away with doing just the left crank, but if it were me, I'd go ahead and do both of them.

Then, use the cartridge BB service instructions to remove the left cup (or the entire BB cartridge if you're so inclined).

Once you have the cup(s) off, clean any old grease or anti-seize from the threads and smear on some fresh grease (or anti-seize). Reinstall the cups, again following the instructions linked to earlier. If you don't own a torque wrench, just tighten the cups as much as possible. It's unlikely that you'll be able to over-torque the BB cups.

When you put the cranks back on, make sure that you have plenty of grease on the crank interface area of the splined spindle. Lack of grease, or dried up grease, is often responsible for the creak that you're hearing.

It's possible too that the BB cartridge is shot. If so, by doing the above, you'll know how to replace it. I wouldn't replace it at the outset though as I think it's likely that the problem may be cured by simply greasing the BB cup threads and crank/spindle interface.
 

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I had a similar issue with square taper bb and shimano STX-RC cranks. I went through two left crank arms becasue they would continulally loosen, I would ride without checking and the crank arm would deform slightly.

Ended up having the LBS replace the cranks and bb with SLX, and I have been very happy, no noise, and much stiffer.
 

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Discussion Starter · #8 ·
The problem has been resolved! KevinB thank you very much for your advice. You were right and it worked perfectly! I went down to my LBS and bought a crank puller and a bottom bracket remover, as well as some grease. I removed the cranks and bottom bracket completely. Every inch inside was covered with sand and dirt so I used a rag with a little degreaser, wiped the threads inside the bike frame clean, the threads on the BB cups clean and everything else in between. After I cleaned everything up I put a thick coat of grease on all threads and inside the BB race, put it all back together and the noise is 100 percent gone! Can you tell I'm excited? haha. Thanks for everyone's input. I appreciate it!
 

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Congrats on fixing it yourself!

(I don't know about you, but I always find it a lot more satisfying to fix problems myself vs letting someone else do it.)
 

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rsalgado said:
I had the same issue, creak on both sides, but needed to alternate pressure to get creak to repeat.
Removed cranks, and found BB was bad, (turned and felt like sand was in there, very rough). Went to Jensonusa for a BB and purchase whole crank BB set-up. Installed myself and took it for a test ride.
Creak, creak, creek, same... hmmm
I knew the BB was bad, so I have new cranks and same creak.
I ride a Giant Anthem, FS. I thought maybe the linkage,
Played with it a little more, now Im thinking may the front end creaks,
headset/ forks ?
I once had a problem like this with my son's bike. The creak in question sounded like a BB related creak. I replaced the BB, but the creak persisted. Further investigation revealed that the cause of the creak was a loose suspension pivot.

The thing is, it's often really hard to figure out where creaks are coming from. And, often, there are multiple creaks! It's useful to see if the noises can be heard by riding out of the saddle. If they can, that immediately eliminates the seat post and seat rails as a source of the noise. If the noise is only heard when riding in the saddle, putting new grease on the seat rails / post will usually cure it.

Otherwise, for me anyway, you make a guess about where the problem lies, and then disassemble that portion of the bike for cleaning, (re)greasing, and reassembly. Repeat on different areas of the bike until the problem goes away.

Sometimes that doesn't work though. I've had creaks that've been due to a crack in the frame. But that highlights the value in trying to keep your bike as quiet as possible. Those creaks that your bike makes are usually due to something not quite working right. Sometimes it's innocuous and won't hurt anything to let it go. But in the case of something like a crack in the frame, knowing about it before your frame catastrophically fails is a very good thing indeed.
 

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Discussion Starter · #11 ·
Oh totally. I spent 39 bucks on the two tools and a tube of grease, but it was 100 percent worth it. The noise is gone, I'll be able to fix it myself if it happens again, and I learned something new! I'm satisfied.
 
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