Replace whole chainset if replace front chainring?

Hi,

I need to replace my front chainring 'cause it's broke. Will I have to
replace my entire chainset? People have told me that the entire chainset
stretches with use and so if you replace one component, you have to replace
the whole lot. I've probably used my bike for at least 1000 rides.

Thanks,
Jack

PS - this thread is related to my one below asking "Fractured front cog?"

Daniel Kelly (AKA Jack) wrote:
Hi,

I need to replace my front chainring 'cause it's broke. Will I have
to replace my entire chainset? People have told me that the entire
chainset stretches with use and so if you replace one component, you
have to replace the whole lot. I've probably used my bike for at
least 1000 rides.

Thanks,
Jack

PS - this thread is related to my one below asking "Fractured front
cog?"

1000 rides on the same chain?!? Even if you only did a mile on each ride,
that's an awful lot of use out of it. Put it out to pasture.

Daniel Kelly (AKA Jack) wrote:
Hi,

I need to replace my front chainring 'cause it's broke. Will I have
to replace my entire chainset? People have told me that the entire
chainset stretches with use and so if you replace one component, you
have to replace the whole lot. I've probably used my bike for at
least 1000 rides.

Hey Jack,
Your crankset is the kind that is all riveted together. You can't replace
just the inner ring.

Your cogs are worn, as others have said. Replacing the whole drive-side arm
is a good thing to do. Check your local bike shop for a used parts bin and
see if they have any right-hand (drive side) crank bits... you don't need to
buy the left side if it's not in need of repair. And as I said before, make
sure you can replace individual chainrings on it.

--
Phil, Squid-in-Training

Hi Phil,
Sorry, I'm getting my terminology confused again. What I meant to ask is:
will I have to replace my entire drive chain (cassette, chain, crank set)? I
know I'll have to throw out my right crank arm and chain rings.

Thanks,

Jack





"ZeeExSixAre" wrote in message
...
Daniel Kelly (AKA Jack) wrote:
Hi,

I need to replace my front chainring 'cause it's broke. Will I have
to replace my entire chainset? People have told me that the entire
chainset stretches with use and so if you replace one component, you
have to replace the whole lot. I've probably used my bike for at
least 1000 rides.

Hey Jack,
Your crankset is the kind that is all riveted together. You can't replace
just the inner ring.

Your cogs are worn, as others have said. Replacing the whole drive-side
arm
is a good thing to do. Check your local bike shop for a used parts bin
and
see if they have any right-hand (drive side) crank bits... you don't need
to
buy the left side if it's not in need of repair. And as I said before,
make
sure you can replace individual chainrings on it.

--
Phil, Squid-in-Training

On Tue, 6 Jul 2004 15:44:37 +0100, "Daniel Kelly \(AKA Jack\)"
wrote:

Hi,

I need to replace my front chainring 'cause it's broke. Will I have to
replace my entire chainset? People have told me that the entire chainset
stretches with use and so if you replace one component, you have to replace
the whole lot. I've probably used my bike for at least 1000 rides.

Maybe.

I'd certainly take a look at the wear on the chain and cassette or
freewheel, but the type of failure you have is not related to wear.
If the chain does not measure as being in need of replacement, there's
no need to trash it. Evaluating the rear sprockets is a little more
subjective, but the guidelines on Sheldon Brown's site provide a place
to start.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Surrealism is a pectinated ranzel.

This applies to bicycles, motorcycles, chainsaws, and anything else where
power is delivered through a chain drive. A new chain, running on a new
sprocket, ideally, makes equal contact with all the teeth that are engaged.
As the chain wears, the pitch increases, so the load is carried more by the
teeth that are just coming into mesh. Of course, the sprocket wears also,
so the load tends to be properly carried by all the teeth. If you now
replace just the chain, the pitch will be shorter than the sprocket pitch,
and all the load will be carried by the teeth that are just going out of
mesh. The wear on the chain and teeth will be rapid. Since the sprocket is
already worn, any metal that it loses will make the problem worse, not
better, so the problem gets worse. The new chain won't last very long.

In practice, chains seem to wear out more rapidly than sprockets, so you can
get away with changing the chain more often than the sprocket. On
chainsaws, the ratio is about three to one. I don't know what it is on
bicycles. On chainsaws, the best practice is to rotate three chains in
service, so they all wear out together, and then replace all three AND the
sprocket. I have never heard of anyone doing this on a bicycle, but,
theoretically, it sounds like a plan.

Comments?

then replace all three AND the sprocket. I have never heard of
anyone doing this on a bicycle, but, theoretically, it sounds like a
plan.

A lot of people do this on their bikes.

--
Phil, Squid-in-Training

"Daniel Kelly \(AKA Jack\)" wrote in message ...
Hi,

I need to replace my front chainring 'cause it's broke. Will I have to
replace my entire chainset? People have told me that the entire chainset
stretches with use and so if you replace one component, you have to replace
the whole lot. I've probably used my bike for at least 1000 rides.

Assuming its a modern, not lowest end, crankset, then you can just
replace the chainrings individually. Chainrings wear a long, long
time. Much longer than chains or rear cassettes. On really low end
bikes, the crank and chainrings may all be one piece. Along with the
bottom bracket too. In that case you would have to replace everything
at once. But assuming you bought the bike in the last 10 years and
paid over $300 for it, you can replace the chainrings individually.

However, it may be cheaper to buy an entire new crankset. Individual
chainrings seem to cost about as much as an entire crankset, including
both chainrings.

On 6 Jul 2004 12:24:18 -0700, (Russell
Seaton) wrote:

Assuming its a modern, not lowest end, crankset, then you can just
replace the chainrings individually.

It's not.

Sunrace Apex; pressed/riveted rings, with the master broken at the
hub.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Surrealism is a pectinated ranzel.

"Daniel Kelly \(AKA Jack\)" wrote in message ...
Hi,

I need to replace my front chainring 'cause it's broke. Will I have to
replace my entire chainset? People have told me that the entire chainset
stretches with use and so if you replace one component, you have to replace
the whole lot. I've probably used my bike for at least 1000 rides.

Thanks,
Jack

PS - this thread is related to my one below asking "Fractured front cog?"

Note that the term "chainset" is usually used to denote left crank,
right crank/spider and chainrings. I think you mean should you change
the whole drive train.

The answer, given the amount of use you have had is probably yes, but
this is unrelated to replacing the chainring.

On the whole chainrings can be replaced without reference to the rest
of the drive train. However, your "1000 rides" will very probably
have worn out your chain, which should be replaced when stretched by
1/8" in a foot. If you have not replaced your chain, it is quite
likely worn beyond this point, and consequently your rear sprockets
will have worn with it to the point that a new chain will very likely
"skip".

My advice would be to measure the chain and replace if needed, if your
new chain skips on the rear sprockets then replace them also. Then
aim to change the chain as it wears out so as to avoid undue sprocket
wear in future.

Andrew Webster