Busted Spider? Loose BB?

[Matt J]

On my Specialized Hardrock MTB (set up with slicks now for crusing), something seems to "click"
whenever I pedal with a moderate to hard effort. I more feel it than hear it. It's mostly on the
downstroke of both the left and right crank. At first, I thought it only happened in the middle
ring, but it appears to occur in the big ring, too. I don't feel any movement of the cranks, so it's
not like they're loose.

The parts are a few years old and have seen a 400-mile loaded tour and 3 years of short
commuting/getting around town (I can't yet drive). They're the stock Specialized cranks (triple, if
that matters). At first I thought it might be a loose spoke in the wheel that tightenend up under
torque and seated differntly. However, I've got on a new wheel now, and a new chain, and it's still
there. I've cleaned the chainrings, too. However, the chainring screws are rusty/stripped, and I
can't get them out, otherwise I'd swap in some different rings. I'd rather not pull off the crank if
I don't have to- isn't that bad for the taper? The cassete is likely rather worn, but this doesn't
seem like a logical cause. Could it be a cracked spider? (Though I don't see any cracks) Could the
BB be broken or cracked or something? Thanks for any ideas.

Matt

 

[Ian S]

"Matt J" <[email protected]> wrote in message
news:[email protected]...
> On my Specialized Hardrock MTB (set up with slicks now for crusing), something seems to "click"
> whenever I pedal with a moderate to hard effort. I

Could be the crank needs to be properly torqued to the bb.

 

[A Muzi]

"Matt J" <[email protected]> wrote in message
news:[email protected]...
> On my Specialized Hardrock MTB (set up with slicks now for crusing), something seems to "click"
> whenever I pedal with a moderate to hard effort. I more feel it than hear it. It's mostly on the
> downstroke of both the left and right crank. At first, I thought it only happened in the middle
> ring, but it appears to occur in the big ring, too. I don't feel any movement of the cranks, so
> it's not like they're loose.
>
> The parts are a few years old and have seen a 400-mile loaded tour and 3 years of short
> commuting/getting around town (I can't yet drive). They're the stock Specialized cranks (triple,
> if that matters). At first I thought it might be a loose spoke in the wheel that tightenend up
> under torque and seated differntly. However, I've got on a new wheel now, and a new chain, and
> it's still there. I've cleaned the chainrings, too. However, the chainring screws are
> rusty/stripped, and I can't get them out, otherwise I'd swap in some different rings. I'd rather
> not pull off the crank if I don't have to- isn't that bad for the taper? The cassete is likely
> rather worn, but this doesn't seem like a logical cause. Could it be a cracked spider? (Though I
> don't see any cracks) Could the BB be broken or cracked or something?

Noises in that area can be diagnosed by standing with your right hand on a support and holding the
front brake tight. Now press alternately on the right crank and then reverse so the left is forward
and press again. An assistant can touch frame/cup, pedal spindle/crank, ring./arm and other
interfaces until you find movement. To your list add pedal bearings, pedal cage loose on body,
toeclip screws, damaged BB bearing, loose cup in frame, loose crank on spindle, loose chainring
bolt. Even small items will resonate and give an annoying sound.

Frequent crank removal/retorque isn't recommended but occasional removal for BB service (even
anually) doesn't seem to affect anything.
--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971

 

[David]

"Matt J" <[email protected]> wrote in message
news:[email protected]...
> ... I don't feel any movement of the cranks, so it's not like they're loose.

It still could be the right crank arm.

>... I've cleaned the chainrings, too. However, the chainring screws are rusty/stripped, and I can't
>get them out, otherwise I'd swap in some different rings.

Could also be the chainring bolts.

> I'd rather not pull off the crank if I don't have to- isn't that bad for the taper? The cassete is
> likely rather worn, but this doesn't seem like a logical cause. Could it be a cracked spider?
> (Though I don't see any cracks) Could the BB be broken or cracked or something?

Some BBs like to creak. Especially in aluminum frames.

> Thanks for any ideas.

Since it happens with either pedal stroke, I would ignore things like pedals for now (unless they're
*both* loose), and look at stuff common to both sides:

Chainring bolts--you should fix them anyway, so why not start there?

Right side taper/crank interface (it's stressed on either pedal stroke too).

Apply rear brake, and push hard down on a pedal (do separately for both sides), observing what
happens to cranks/rings/chainstays, etc. Look for interference, frame cracks, etc. I've had a
click caused by chainring pins hitting the chain-suck plate (which was really a chain-destroy
plate), and another by the crank hitting the chainstay (which was flexing due to a crack).

If everything else is OK, I might reinstall the BB with well lubed threads.

David

 

[Maurie Abbott]

My guess is the the chain is riding up the chain ring teeth and crunching up. You can check this by
applying force to the pedal and observing what the chain does around the chain ring.

Try another chain ring.

Most shimano MTB chainrings have a note advising that a IG chain, not a HG chain, must be used. I
don't know if this has anything to do with your problem.

Regards, Maurie Abbott
===========================
Matt J wrote:
>
> On my Specialized Hardrock MTB (set up with slicks now for crusing), something seems to "click"
> whenever I pedal with a moderate to hard effort. I more feel it than hear it. It's mostly on the
> downstroke of both the left and right crank. At first, I thought it only happened in the middle
> ring, but it appears to occur in the big ring, too. I don't feel any movement of the cranks, so
> it's not like they're loose.
>
> The parts are a few years old and have seen a 400-mile loaded tour and 3 years of short
> commuting/getting around town (I can't yet drive). They're the stock Specialized cranks (triple,
> if that matters). At first I thought it might be a loose spoke in the wheel that tightenend up
> under torque and seated differntly. However, I've got on a new wheel now, and a new chain, and
> it's still there. I've cleaned the chainrings, too. However, the chainring screws are
> rusty/stripped, and I can't get them out, otherwise I'd swap in some different rings. I'd rather
> not pull off the crank if I don't have to- isn't that bad for the taper? The cassete is likely
> rather worn, but this doesn't seem like a logical cause. Could it be a cracked spider? (Though I
> don't see any cracks) Could the BB be broken or cracked or something? Thanks for any ideas.
>
> Matt

 

[Jeff Wills]

"A Muzi" <[email protected]> wrote in message news:<[email protected]>...
> Noises in that area can be diagnosed by standing with your right hand on a support and holding the
> front brake tight. Now press alternately on the right crank and then reverse so the left is
> forward and press again. An assistant can touch frame/cup, pedal spindle/crank, ring./arm and
> other interfaces until you find movement. To your list add pedal bearings, pedal cage loose on
> body, toeclip screws, damaged BB bearing, loose cup in frame, loose crank on spindle, loose
> chainring bolt. Even small items will resonate and give an annoying sound.
>
> Frequent crank removal/retorque isn't recommended but occasional removal for BB service (even
> anually) doesn't seem to affect anything.

Once upon a time I had a click/squeak that I couldn't get rid of, even with several iterations of
removing, cleaning, and replacing various crank parts. I finally got around to removing the
pedals, cleaning the threads, and reinstalling them with fresh grease on the threads. After that,
no more click.

Jeff

 

[Matt J]

"David" <[email protected]> wrote in message
news:<[email protected]>...
> > ... I don't feel any movement of the cranks, so it's not like they're loose.
>
> It still could be the right crank arm.

I'll take it off and try the bolts, then reinstall it with proper torque.

> >... I've cleaned the chainrings, too. However, the chainring screws are rusty/stripped, and I
> >can't get them out, otherwise I'd swap in some different rings.
>
> Could also be the chainring bolts.

I'll get some different ones from the LBS... how do I get out the old ones, though, if they're
stripped? Drill them out?

> > I'd rather not pull off the crank if I don't have to- isn't that bad for the taper? The cassete
> > is likely rather worn, but this doesn't seem like a logical cause. Could it be a cracked spider?
> > (Though I don't see any cracks) Could the BB be broken or cracked or something?
>
>
> Some BBs like to creak. Especially in aluminum frames.

Doesn't really sound like a creak. Nothing really audible at all, it's just a "click" you hear
when pedaling.

> > Thanks for any ideas.
>
>
> Since it happens with either pedal stroke, I would ignore things like pedals for now (unless
> they're *both* loose), and look at stuff common to both sides:

You're right - I've had two differnt pairs of pedals on it - to no avail.

I'll try the rest - thanks for the ideas! Matt

 

[Matt J]

I just put on a new Sram PC-58 chain - dunno how that relates to IG vs HG shimano. What is the
difference, anyway? After looking at the bike again, I rememebered it's got this funky front
derailleur, attached to the drive side BB it looks like, with the cable routed around the bottom of
the BB so it pulls the der. down to shift into a higher ring. It looks as if the only attachment is
onto the BB, with a thing sticking up onto the seat tube to sorta stablize it. Anyone had problems
with this kinda doohickey before? Am I stuck using it because there's no cable stop for a clamp-on
fder? I played with it for a little bit, looked at all the stays and BB welds - no frame cracks, and
I re-tightened the crankarms. It feels almost as if something is rattling slightly... Thanks for the
input! Matt

Maurie Abbott <[email protected]> wrote in message news:<[email protected]>...
> My guess is the the chain is riding up the chain ring teeth and crunching up. You can check this
> by applying force to the pedal and observing what the chain does around the chain ring.
>
> Try another chain ring.
>
> Most shimano MTB chainrings have a note advising that a IG chain, not a HG chain, must be used. I
> don't know if this has anything to do with your problem.
>
> Regards, Maurie Abbott
> ===========================

 

[Ant]

> I'll get some different ones from the LBS... how do I get out the old ones, though, if they're
> stripped? Drill them out?
> > I'll try the rest - thanks for the ideas!
> Matt

I'm no shop mechanic, and you might be, so forgive me if this is silly advice, but are you sure your
chainring bolts are stripped? I've known folks who thoguht they were stripped, but actually just
didnt know that what looks like a bolt that screws into the spider is actually a two piece assembly:
a chainring bolt plus a chainring nut.

if all you are doing to remove them is using an allen wrench and they are spinning, then more likely
than not they are not stripped but just turning within their hole in the crank (both nut and bolt
turning together). for this, either buy the two dollar chainring bolt tool (park has one, you could
also probably make one that would do the trick from a scrap of thin steel and a file. it holds the
notches in the chainring nut from the back) or maybe just slather the bolt assembly in penetrating
oil and hope it comes undone better next time. maybe grab it with pliers from the back?

cheers,

anthony

 

[A Muzi]

"Matt J" <[email protected]> wrote in message
news:[email protected]... -snip click in bottom of bike-

> I'll get some different ones from the LBS... how do I get out the old ones, though, if they're
> stripped? Drill them out?

Yes. If you're sure there's no other way, skin off the top with a 3/8" bit. It will drop right out.

When you install new chainring bolts, lube the bolt with grease but leave the nut dry. The nut will
stick in the inner ring so torquing the bolt is straightforward with only an allen wrench.
--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971

 

[Matt J]

[email protected] (ant) wrote in message
news:<[email protected]>...
> > I'll get some different ones from the LBS... how do I get out the old ones, though, if they're
> > stripped? Drill them out?
> > > I'll try the rest - thanks for the ideas!
> > Matt
>
> I'm no shop mechanic, and you might be, so forgive me if this is silly advice, but are you sure
> your chainring bolts are stripped? I've known folks who thoguht they were stripped, but actually
> just didnt know that what looks like a bolt that screws into the spider is actually a two piece
> assembly: a chainring bolt plus a chainring nut.

I am no shop mechanic either (if you were referring to me) but the problem is that the allen wrench
does not grab the bolt - nothing is turning but the wrench. I tried some penetrating lube, but to no
avail. Is it possible that the bolt is customary sized? I'm using a metric wrench (4mm) to try to
unscrew it. Maybe I'll run out and get a nut-holder like you suggested, see if I can do anything
with that. They're weird, though - the same nut for all three rings. Isn't that unusual? Matt

 

[Matt J]

[email protected] (ant) wrote in message
news:<[email protected]>...
> ah! im willing to bet that you actually need a 5mm allen wrench. theyre more standard for bike
> work, and if my mem serves me correctly, are the correct one for standard stack bolts. try a 5mm.
> if that makes the bolt come out, great. if it makes the entire bolt and nut turn, then you need to
> make or buy that special little hold-it-from-behind tool
>
> cheers anthony

Nope, tried that first. Definitely too big. I think they're just stripped. I'm just living with it
for now. Unless something breaks, they're working well enough. Thanks though Matt