Chain skipping

Arnaud said:

Hi all,

The chain on my touring bike is slightly skipping on a
couple of rear cogs (the 2 cogs above the smallest). It is
quite subtle for the moment but it's starting to get
annoying.

I measured the distance between 12 links of the chain and
it is slightly above 12" by 1/10th of an inch. I don't
know if 1/10th of an inch is enough to cause the skipping
but I think the chain has to be replaced. From what I read
I need to also replace the cassette. Is that all I should
replace or should I also change the front middle ring (the
one I use the most) ?

The chain has about 1500 miles of use, mostly during
winter. I lubed it quite often although I degreased it
only 3 times. Is this normal to have a worn chain after
only 1500 miles?? The chain on my MTB lasted 5000 miles
until I had to replace the whole drivetrain...

Cheers, Arnaud.

My suggestion would be to fit a new chain and see how it
feels. If it still doesn't feel quite right then buy a new
cassette. If it still doesn't feel right replace the jockey
wheels in the mech etc etc. I wouldn't rush out and buy a
whole new drivechain, expecially if the chain is only
slightly overworn.

Arnaud said:

Hi all,

The chain on my touring bike is slightly skipping on a
couple of rear cogs (the 2 cogs above the smallest). It is
quite subtle for the moment but it's starting to get
annoying.

I measured the distance between 12 links of the chain and
it is slightly above 12" by 1/10th of an inch. I don't
know if 1/10th of an inch is enough to cause the skipping
but I think the chain has to be replaced. From what I read
I need to also replace the cassette. Is that all I should
replace or should I also change the front middle ring (the
one I use the most) ?

The chain has about 1500 miles of use, mostly during
winter. I lubed it quite often although I degreased it
only 3 times. Is this normal to have a worn chain after
only 1500 miles?? The chain on my MTB lasted 5000 miles
until I had to replace the whole drivetrain...

Cheers, Arnaud.

My suggestion would be to fit a new chain and see how it
feels. If it still doesn't feel quite right then buy a new
cassette. If it still doesn't feel right replace the jockey
wheels in the mech etc etc. I wouldn't rush out and buy a
whole new drivechain, expecially if the chain is only
slightly overworn.

David Waters said:

My suggestion would be to fit a new chain and see how it
feels. If it still doesn't feel quite right then buy a new
cassette. If it still doesn't feel right replace the
jockey wheels in the mech etc etc. I wouldn't rush out and
buy a whole new drivechain, expecially if the chain is
only slightly overworn.

Yup maybe just changing the chain will be enough... Off to
the LBS in the morning then 🙂

Thanks Arnaud

Arnaud said:

The chain on my touring bike is slightly skipping on a
couple of rear cogs (the 2 cogs above the smallest). It is
quite subtle for the moment but it's starting to get
annoying.

I measured the distance between 12 links of the chain and
it is slightly above 12" by 1/10th of an inch. I don't
know if 1/10th of an inch is enough to cause the skipping

Only if the cogs have already been well worn from
previous chain(s).

Quoted message said:

but I think the chain has to be replaced.

Now will be a good time to change it anyway.

Quoted message said:

From what I read I need to also replace the cassette.

You wouldn't normally need to at this point with sprockets
in good condition but they won't be if the chain really is
skipping over the teeth. Check for stiff links in the chain,
eliminate any gear shifting problems and anything else you
can think of.

Quoted message said:

Is that all I should replace or should I also change the
front middle ring (the one I use the most) ?

Chainrings outlast rear sprockets. Only change the chainring
if a new chain skips on it.

Quoted message said:

The chain has about 1500 miles of use, mostly during
winter. I lubed it quite often although I degreased it
only 3 times. Is this normal to have a worn chain after
only 1500 miles??

Not exactly uncommon to elongate the chain by 1/10". But is
this the first chain with these sprockets? The chain
shouldn't be skipping yet if so.

Quoted message said:

The chain on my MTB lasted 5000 miles until I had to
replace the whole drivetrain...

You can normally do that or more mileage with road bike
transmission as well, it's just not a good idea to because
chainrings are expensive and they will eventually wear out
like that.

Note. Excessive wear can be caused by crossing the chain
over too much (small-small, big-big, etc).

~PB

Arnaud said:

Yup maybe just changing the chain will be enough...

Nope, changing the chain alone will make the problem WORSE
if the chain really is skipping due to sprocket wear.

~PB

Pete Biggs said:

Chainrings outlast rear sprockets. Only change the
chainring if a new chain skips on it.

Why do chainrings outlast sprockets? For most of my cycling,
the load is shared between two chainrings but a whole stack
of sprockets.

Are sprockets softer?

in message <[email hidden]>, David Waters

(') said:

Quoted message said:

I measured the distance between 12 links of the chain and
it is slightly above 12" by 1/10th of an inch. I don't
know if 1/10th of an inch is enough to cause the skipping
but I think the chain has to be replaced.

From what I read I need to also replace the cassette. Is
that all I should replace or should I also change the
front middle ring (the one I use the most) ?

My suggestion would be to fit a new chain and see how it
feels. If it still doesn't feel quite right then buy a new
cassette.

The problem with that solution is that by the time you've
desided you

new cassette...

If any part of the drive train is significantly more worn
than any other it will hugely accelerate wear in the other
components.

Replace them all at once. It's a [censored], it's expensive, but
it's a _lot_ cheaper in the long run. And in future, monitor
chain wear and replace early with good quality chain.

--
[email hidden] (Simon Brooke)
jasmine.org.uk~simonOpen ↗

;; I'd rather live in sybar-space

in message <[email hidden]>, Al C-F

(') said:

Pete Biggs said:

Chainrings outlast rear sprockets. Only change the
chainring if a new chain skips on it.

Why do chainrings outlast sprockets? For most of my
cycling, the load is shared between two chainrings but a
whole stack of sprockets.

More teeth. The wear is shared out equally among the teeth
of the sprocket, so each of the teeth on an eleven tooth
sprocket will get four times the wear of each of the teeth
on a 44 tooth sprocket.

--
[email hidden] (Simon Brooke)
jasmine.org.uk~simonOpen ↗

...but have you *seen* the size of the world
wide spider?

Simon Brooke:

Quoted message said:

More teeth. The wear is shared out equally among the teeth
of the sprocket, so each of the teeth on an eleven tooth
sprocket will get four times the wear of each of the teeth
on a 44 tooth sprocket.

Except on a road bike you'd be more likely to be running the
chain on a 48 or 50 or 52 tooth chainring when it's on the
11 tooth rear sprocket, so the difference is even greater.

However, the big chainring would get considerably more than
four times the use of an 11 tooth sprocket on any bike
ridden by me (not that I have such a thing - 52*14 is quite
a big enough gear for my knees, thanks), so that would even
out the wear a bit, which is what the previous poster was
getting at, I think.

And yet the smaller sprockets *do* wear faster, even with
less use - I think I know why, but I couldn't begin to
explain it. Something to do with torque. I expect Sheldon
Brown probably has something about it on his site.

d.

Al C-F said:

Quoted message said:

Chainrings outlast rear sprockets. Only change the
chainring if a new chain skips on it.

Why do chainrings outlast sprockets? For most of my
cycling, the load is shared between two chainrings but a
whole stack of sprockets.

It's mainly because they're larger (on a road bike at
least). I think being at the *front* might make a difference
as well, though I don't understand why.

Quoted message said:

Are sprockets softer?

Nope, usually harder!

~PB

Al C-F <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

Pete Biggs said:

Chainrings outlast rear sprockets. Only change the
chainring if a new chain skips on it.

Why do chainrings outlast sprockets? For most of my
cycling, the load is shared between two chainrings but a
whole stack of sprockets.

1. The sprockets go round more times than the chainrings so
get more wear.

2. Chainrings generally do not give problems until they are
quite badly worn. Rather than skipping, when they do
finally wear out the chain will tend to jam or "suck"
(i.e. fail to disengage at the bottom) especially when
changing gear from a larger ring to a smaller one. This
can actually be quite dangerous.

--
Dave...

Dave Kahn said:

2. Chainrings generally do not give problems until they
are quite badly worn. Rather than skipping, when they
do finally wear out the chain will tend to jam or
"suck" (i.e. fail to disengage at the bottom)
especially when changing gear from a larger ring to a
smaller one. This can actually be quite dangerous.

Chain can skip on chainrings as well. I think chain suck is
more common on MTB chainsets, with the smaller rings.

~PB

Dave Kahn said:

2. Chainrings generally do not give problems until they
are quite badly worn. Rather than skipping, when they
do finally wear out the chain will tend to jam or
"suck" (i.e. fail to disengage at the bottom)
especially when changing gear from a larger ring to a
smaller one. This can actually be quite dangerous.

Chain can skip on chainrings as well. I think chain suck is
more common on MTB chainsets, with the smaller rings.

~PB

"Pete Biggs" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Al C-F said:

Quoted message said:

Chainrings outlast rear sprockets. Only change the
chainring if a new chain skips on it.

Why do chainrings outlast sprockets? For most of my
cycling, the load is shared between two chainrings but a
whole stack of sprockets.

It's mainly because they're larger (on a road bike at
least). I think being at the *front* might make a
difference as well, though I don't understand why.

The pressure load at the front is shared over many more
teeth. The wear is a nonlinear function of the pressure on
the teeth.

Quoted message said:

Quoted message said:

Are sprockets softer?

Nope, usually harder!

Depends. If they are hard, they are generally case hardened.
Once the hardened layer wears through, the softer metal
beneath wears very rapidly.
--
"To live in San Francisco and just not care that there are
naked triathletes running across your lawn, that's just a
waste of exhibitionism."
- Kibo

"Pete Biggs" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Al C-F said:

Quoted message said:

Chainrings outlast rear sprockets. Only change the
chainring if a new chain skips on it.

Why do chainrings outlast sprockets? For most of my
cycling, the load is shared between two chainrings but a
whole stack of sprockets.

It's mainly because they're larger (on a road bike at
least). I think being at the *front* might make a
difference as well, though I don't understand why.

The pressure load at the front is shared over many more
teeth. The wear is a nonlinear function of the pressure on
the teeth.

Quoted message said:

Quoted message said:

Are sprockets softer?

Nope, usually harder!

Depends. If they are hard, they are generally case hardened.
Once the hardened layer wears through, the softer metal
beneath wears very rapidly.
--
"To live in San Francisco and just not care that there are
naked triathletes running across your lawn, that's just a
waste of exhibitionism."
- Kibo

Mark South said:

Quoted message said:

It's mainly because they're larger (on a road bike at
least). I think being at the *front* might make a
difference as well, though I don't understand why.

The pressure load at the front is shared over many more
teeth. The wear is a nonlinear function of the pressure on
the teeth.

Yes but what about when the chainring happens to be
*smaller* than the largest rear sprockets (as in the case
with some triple inner chainrings)? I think they still wear
slower in that case as well.

Quoted message said:

Quoted message said:

Quoted message said:

Are sprockets softer?

Nope, usually harder!

Depends. If they are hard, they are generally case
hardened. Once the hardened layer wears through, the
softer metal beneath wears very rapidly.

Chainrings are often aluminium. Rear sprockets are usually
steel. Just have a go at filing them if you doubt which
are harder.

~PB

Mark South said:

Quoted message said:

It's mainly because they're larger (on a road bike at
least). I think being at the *front* might make a
difference as well, though I don't understand why.

The pressure load at the front is shared over many more
teeth. The wear is a nonlinear function of the pressure on
the teeth.

Yes but what about when the chainring happens to be
*smaller* than the largest rear sprockets (as in the case
with some triple inner chainrings)? I think they still wear
slower in that case as well.

Quoted message said:

Quoted message said:

Quoted message said:

Are sprockets softer?

Nope, usually harder!

Depends. If they are hard, they are generally case
hardened. Once the hardened layer wears through, the
softer metal beneath wears very rapidly.

Chainrings are often aluminium. Rear sprockets are usually
steel. Just have a go at filing them if you doubt which
are harder.

~PB

On Tue, 18 May 2004 19:03:37 +0100, "Pete Biggs"
<[email hidden]> wrote in message
<[email hidden]>:

Quoted message said:

Chainrings are often aluminium. Rear sprockets are usually
steel. Just have a go at filing them if you doubt which
are harder.

Maybe wear particles become embedded in the soft
material, causing it to wear the chain rather than the
chain to wear it?

Guy
--
May contain traces of irony. Contents liable to settle after posting.
chapmancentral.co.ukchapmancentral.co.ukOpen ↗

88% of helmet statistics are made up, 65% of them at Washington University

On Tue, 18 May 2004 19:03:37 +0100, "Pete Biggs"
<[email hidden]> wrote in message
<[email hidden]>:

Quoted message said:

Chainrings are often aluminium. Rear sprockets are usually
steel. Just have a go at filing them if you doubt which
are harder.

Maybe wear particles become embedded in the soft
material, causing it to wear the chain rather than the
chain to wear it?

Guy
--
May contain traces of irony. Contents liable to settle after posting.
chapmancentral.co.ukchapmancentral.co.ukOpen ↗

88% of helmet statistics are made up, 65% of them at Washington University