Chainwheels

elyob said:

Hi, My chain is becoming dangerously stretched, so I've started
fitting my replacement cassette and chain. I've just stopped in the
middle as I'm wondering about the chainwheels ... they're about 4
years old, don't really give any trouble, but should they be replaced
periodically?

Chainrings tend to outlive cassettes, sometimes several cassettes,
especially the larger ones as they're so much larger than rear
sprockets--load is spread more evenly.

I would fit the new chain and see how it works on the existing chainrings.
No need for new rings if it works fine. But it might skip (or cause some
other nastiness) if the ring(s) have already been significantly worn from
the stretched chain. Judjing from appearance is not good enough, IMO.

~PB

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

Quoted message said:

elyob said:

Hi, My chain is becoming dangerously stretched, so I've started
fitting my replacement cassette and chain. I've just stopped in the
middle as I'm wondering about the chainwheels ... they're about 4
years old, don't really give any trouble, but should they be replaced
periodically?

Chainrings tend to outlive cassettes, sometimes several cassettes,
especially the larger ones as they're so much larger than rear
sprockets--load is spread more evenly.

I would fit the new chain and see how it works on the existing chainrings.
No need for new rings if it works fine. But it might skip (or cause some
other nastiness) if the ring(s) have already been significantly worn from
the stretched chain. Judjing from appearance is not good enough, IMO.

I was more thinking of the little wheels on the rear gears. The little
hanging derailleur. The front chain rings were replaced last chain, so I'm
hoping they're okay.
Thanks

elyob said:

I was more thinking of the little wheels on the rear gears. The little
hanging derailleur. The front chain rings were replaced last chain,
so I'm hoping they're okay.

Oh the jockey wheels. They don't take a lot of load so aren't important
to replace frequently. They can last for tens of thousands of miles.
Perhaps fair enough to go by appearance for them: the teeth become spikey
when worn out, but bear in mind that top and bottom wheels can be
different from new. Also most top jockey wheels have "float", making them
feel wobbly--this is normal.

~PB

elyob said:

Hi, My chain is becoming dangerously stretched, so I've started fitting my
replacement cassette and chain. I've just stopped in the middle as I'm
wondering about the chainwheels ... they're about 4 years old, don't really
give any trouble, but should they be replaced periodically?

Clean them up. Do they spin without resistance? Yes, they're fine. No,
change them.

I had some SRAM ones go after a few thousand miles, but the more
expensive ceramic bushed Sante ones are still going just fine after 30K
plus.

...d