Bottom bracket issues

[marcdominic]

Folks,

My bottom bracket (I believe) maybe on the way out (again). Sometimes it clicks with every one crank revolution (hence suspect bottom bracket), however at other times it does not…. The BB is Shimano XT sealed. Any ideas on what may cause this – perhaps a flattened bearing? Sometimes it can be soundless for days… Other times it is loud and most annoying… When it is making noise (not right now presently), the noise is amplified when peddling harder.
The BB was replaced only two years ago (I think, might be three – can’t rightly remember) and I only (now) use the bike for regular commuting….

Bike is Kona Caldera 1999 (with bits and bobs replaced and still going strong!).

[DaveM]

Could just be a loose crank arm or pedal. Check those before you assume it's the BB

[Theo]

Just repaired my BB. Was making a noise on every down peddle for about the last two months. Was driving me nuts. Have a FCR3 Giant with a cartridge type BB. Removed and cleaned the carriage and bracket. Reassembled and torqued it to spec's. No more noise. Probably was the torque. When I pulled the crank's, I grabbed both sides of the spindle and with a lot of effort ,was able to get it to move just a bit. We'll see how long this will last. I torqued the BB to 30ft lbs and the crank's to 35ft lbs.

[marcdominic]

Dave,

I thought about the pedal, but since the ‘click’ happens at the same place on the crank I suspect BB. Crank on drive train side has recently been removed to fit new middle chain ring – by LBS (I didn’t have the time to do it myself). In retrospect, this (reported symptom) has occurred before that change….

I think, when I get the chance, I’ll simply change the pedals (to a **** set) and see if it still occurs…. If it does, I’ll check the crank arms as your suggestion – I mean at the moment the seem/feel fine…. Are Shimano BBs any good – I’m sure I don’t cycle hard on them but it has been three years (perhaps)…? Would you recommend another manufacturer for replacement…?

[marcdominic]

Theo,
Thanks for your info – this indeed could be an issue but the BB was fitted three years ago… Unfortunately, I do not have the tools to remove, replace and re-tighten it to the correct torque. I’ll have to have a think…
The ‘clicking’ is now permanent, after the above checks prove negative, I’ll go for a new BB…

[DaveM]

Shimano BB's are fine. The quality varies with price of course, but they typically last years.
You might try slipping the chain off the inner chain ring so you can rotate the cranks without anything touching them. If that feels very smooth with no side to side play, it would indicate (but not prove) that the BB is fine.
My first guess would be loose crank arm or pedal. Sometimes re-installing the pedals with a little grease on the threads will cure this. But as stated above, these noises can be tricky to track down. good luck

[wolfc]

I am also having problems with a click noise coming from the bottom bracket, cranks or petals. I had this same issue last fall and the LBS replaced the bottom bracket. the sound started coming back the last week or two. As before the sound is most frequent on the hot, humid days. I am looking for some method to determine if its the bottom bracket, cranks or the petals. everything seems to be tight.

[wolfc]

For anyone who is interested, I talked to my LBS and they said that another customer had the same problem. After replacing a lot of parts and many calls to Giant, they figured out that adding a little thread tape to the took care of the problem. It also took care of my problem! Supposedly it's related to the humidity and it'd make sense since its been humid all week.

[marcdominic]

Guys,

I haven’t had chance to thoroughly check the situation out yet – I’ve had barely the time to clean the chain but that’s been done…. It too has been humid around here lately, however the clicking has gone away (wolfc - maybe with the slightly colder weather that we’re having here now)! I have an opportunity to change the BB on Friday but as I said things seem to be OK right now….

This whole thing puzzles me slightly as before the clicking has gone away with no attention/alterations (knowingly – you’re always adjusting things). Drive chain is superb and bike is great (for an oldie) at the mo…

Marc Dominic.

[treky]

I thought I was having a BB issue too. Then my chain snapped so I replaced it with a new one and the BB feels nice and smooth again.

[marcdominic]

Been away for a while from this thread: I no longer have the clicking BB - yet I've done nothing to repair the existing yet tune and clean the drive chain. It's a little slower cycling on the snow here right now but I remember the issue disappeared back in Nov when the weather was fine... Hmm...

[Alex Ramon]

As DaveM mentioned, one of the most common causes of clicking is dry pedal threads. Try removing the pedals, greasing the threads, and then re-install them. For those who've never replaced pedals, here's a video

[MTBconverter]

what type of BB is this?

[Jordan300]

It looks like some type of square taper bottom bracket. Do you need help removing it?

[MTBconverter]

yes please! is it a sealed unit?

[cyclerUK]

(01-23-2010, 03:02 PM)MTBconverter Wrote:  yes please! is it a sealed unit?

We could do with a photo of the other side as well.

I don't think it's a "sealed unit"?

Undo and remove the crank arms (you will need a "crank puller").
Remove the "locknut", one with the 2 notches. ( "C Spanner or a hammer and drift).
Make sure which way the thread is?

Unscrew the "cup" and then do the same to the other side.
The other side should have an opposite thread so be careful !!

See:- http://www.sheldonbrown.com/tooltips/bbcups.html
And:- http://www.parktool.com/repair/readhowto.asp?id=93

[MTBconverter]

Well so far I have skinned my elbow, ruined a crank remover, de-threaded both sides of my crank, destroyed my my way to get to work on monday and have totally given up on trying to save the planet. That's it - I am buying a car.

When I watched these tutorials after trying the jobs and following the instructions one thing strikes me, but then I a newcomer to the world of DIY bike repairs. Almost no effort is used in getting fly-wheels, cranks off, etc.... For some weird reason, i.e. my bikes are used and not preprepared and pregreased, it takes a monumental effort to undo any major fixing on my bike.

Maybe there should be a tutorial part II to each of the other tutorials that deal with an unmovable bolt with the presenter covered in blood and helpful hints on how to stop blood running all over the place and then how to get to work when the crank removal tool is stuck in the crank and you bearings are f**ked...

Its my fault, I know that. It just looked so easy and effortless that I thought that even a fool like me could do it. My missus tells me I am easily led and she appears to be right

[cyclerUK]

(01-23-2010, 09:10 PM)MTBconverter Wrote:  Well so far I have skinned my elbow, ruined a crank remover, de-threaded both sides of my crank, destroyed my my way to get to work on monday and have totally given up on trying to save the planet. That's it - I am buying a car.

When I watched these tutorials after trying the jobs and following the instructions one thing strikes me, but then I a newcomer to the world of DIY bike repairs. Almost no effort is used in getting fly-wheels, cranks off, etc.... For some weird reason, i.e. my bikes are used and not preprepared and pregreased, it takes a monumental effort to undo any major fixing on my bike.

Maybe there should be a tutorial part II to each of the other tutorials that deal with an unmovable bolt with the presenter covered in blood and helpful hints on how to stop blood running all over the place and then how to get to work when the crank removal tool is stuck in the crank and you bearings are f**ked...

Its my fault, I know that. It just looked so easy and effortless that I thought that even a fool like me could do it. My missus tells me I am easily led and she appears to be right

Do I detect a hint of frustration ??

[Bill]

(01-23-2010, 09:10 PM)MTBconverter Wrote:  Well so far I have skinned my elbow, ruined a crank remover, de-threaded both sides of my crank, destroyed my my way to get to work on monday and have totally given up on trying to save the planet. That's it - I am buying a car.

When I watched these tutorials after trying the jobs and following the instructions one thing strikes me, but then I a newcomer to the world of DIY bike repairs. Almost no effort is used in getting fly-wheels, cranks off, etc.... For some weird reason, i.e. my bikes are used and not preprepared and pregreased, it takes a monumental effort to undo any major fixing on my bike.

Maybe there should be a tutorial part II to each of the other tutorials that deal with an unmovable bolt with the presenter covered in blood and helpful hints on how to stop blood running all over the place and then how to get to work when the crank removal tool is stuck in the crank and you bearings are f**ked...

Its my fault, I know that. It just looked so easy and effortless that I thought that even a fool like me could do it. My missus tells me I am easily led and she appears to be right

Quick question and not trying to tick you off, no one here is, did you remove the retainer bolt/nut before trying to use the crank remover? Reason I asked is because I did not remove the retainer bolt/nut inside the the crank. After going over everything I found what it was.

Next the Bottom Bracket type is something I have never seen but I am willing to bet that it is similar to the newer low end MTB's (i.e. Next, Mongoose, etc). It has the lockring on it which you have to loosen FIRST (the ring with three holes around it). Take note on the threading of these bearing cups/races, I believe they are right hand threads on the non drive side of the bike and left hand threaded on the drive side. Sorry you went through heck and all the frustration.

Not all is lost just go to the LBS, as far as DIY and newcomer most of us were and still are newcomers. Take a breathe and go back at it.

Good day to you and hope things work out,
Bill

[jr14]

(01-23-2010, 09:10 PM)MTBconverter Wrote:  Maybe there should be a tutorial part II to each of the other tutorials that deal with an unmovable bolt with the presenter covered in blood and helpful hints on how to stop blood running all over the place and then how to get to work when the crank removal tool is stuck in the crank and you bearings are f**ked...

Well, apart from the bloody presenter and coarse language, a video about removing stuck parts, ie. stem, seatpost, frozen threads, etc., isn't a bad idea.

What do you think Alex?

I like spraying whatever is stuck with WD-40 and letting it sit for a couple minutes. Repeating as necessary until whatever is stuck is unstuck.

Another trick I learned for seat posts especially, is heating the seat post with a torch (from the INSIDE unless you want to repaint the bike) and then discharging a CO2 cartridge immediately afterwards into the post. The heat expands the metal, which in turn expands the frame, then the super cold CO2 shrinks the seat post FAST, and it frees the post. Popping and crackling sounds are normal.

This probably wouldn't work for cranks, but the WD-40 might.