Bicycle Mechanics - bottom bracket upgrade

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View Full Version : bottom bracket upgrade


azgordo
07-18-07, 03:36 PM
i am a clyde riding about 160 mi a week on a trek sport 7.3. at about 1000 mi i had to take it into the shop for noise from the bottom bracket. now at about 2000 mi the noise is back. i rode a giant tcr ll elete about 12000 miles without any bottom bracket problems and since that was a much more expensive bike, i assume the quality of componets was better i have planed on a chain replacement at 2500 miles and wonder if there is a bottom bracket upgrade that i might get at the same time to solve this problem.

thanks
azgordo


neil0502
07-18-07, 04:45 PM
What about the bottom bracket upgrade of removing your existing bracket, cleaning the threads, greasing the threads, and re-installing the bb to the appropriate torque spec.

You sure that's been tried??

What was the noise, and under what circumstances did you hear it?

Ya' prolly' oughta' know for sure that your bb is bad before you toss it.

My $0.02, anyway.

tellyho
07-18-07, 05:23 PM
Or pull the BB and teflon tape the threads of the cartridge and NDS cup. Lots of tape. Reinstall.


neil0502
07-18-07, 05:34 PM
What about my mom?

Not startin' $hit. Just curious.

tellyho
07-18-07, 05:37 PM
Tried to come up with a clever tag. Failed.

KeyLime
07-18-07, 07:13 PM
just went out for ride and noticed a noise from my BB as well. Bike is a Schwinn Fastback LTD with 1050 miles. Had same problem about 6 weeks ago and took to LBS and they disassembled and said something was not seated property. Bike at that time only had about 150 miles on it.
Now, its doing it again. This time I notice when I take my weight off the seat the noise goes away.
I weigh 283 lbs (down from 300 when I first started riding).
Looks like I am back to bike shop tomorrow.

azgordo
07-18-07, 07:25 PM
its a rapid clicking noise when i put a lot of presure on the crank like when climbing. same noise as before. i dont want to be down every 1000 miles and as much as i wish i were, i am not a mechanic

azgordo

neil0502
07-18-07, 08:16 PM
I still wouldn't be sure that you have a faulty bb.

You ought to take it to the Local Bike Shop and ask the mechanic to look at it. More than likely, the procedure I (or the person after me) listed will end your problem. Either way, they can LOOK AT the bb when they pull it, check for bearing play, etc., etc.

If it NEEDS replacement, you won't have wasted any money on the labor ... since the old one had to come out anyway.

If you bought it NEW from the shop, take it back to where you bought it. They should look into it for free, under warranty, and--if it IS just a lube-fix sort of creak--they should FIX it for free, too.

ang1sgt
07-19-07, 05:35 AM
On a bike at the Price Point of the TREK 7.3, your bottom bracket is not going to be nearly the strength that it should be for a Clyde to be pounding on as much as you have so far. This is not a slight on you to be sure. As a Clyde myself, I believe that Shimano LX is the minimum that I would put into a bike for guys and gals our size. All the manufacturers try and spec out parts they feel will serve the purpose at a given price point. They can shave a lot of the price of manufacture if they can stuff a Tourney or Alivio quality BB over a Deore or LX. A UN-53 or UN-73 should hold up for you and that would be my suggestion.

Chris

HillRider
07-19-07, 06:24 AM
What is the make and model of the crank and bb? If it's an FSA or Truvative ISIS type that could be the problem as a lot of ISIS bottom brackets are known to be trouble and have poor durability.

KeyLime
07-19-07, 08:02 AM
mine is a FSA. *leaving soon for the LBS... *

KeyLime
07-19-07, 06:02 PM
mine is a FSA. *leaving soon for the LBS... *

I feel so stupid.... it turned out to be a loose chain ring and pedal.. duh.