Average Lifetime of Bike Parts

Aside from tires what other parts are prone to wear out over time and
at what rate?
I am suspecting eventually the chain will go along and later the crank
and the cassette. But what's a typical mileage number assuming a
decently maintained bike?

Jorg Lueke wrote:
Aside from tires what other parts are prone to wear out over time and
at what rate?
I am suspecting eventually the chain will go along and later the crank
and the cassette. But what's a typical mileage number assuming a
decently maintained bike?

Of course every part is subject to wear, or fatigue. Chains would be
the next in line after tires. There is a way to check the chain, in
that as it wears, it lengthens. Any chain measuring more than 12+1/8
inches for 12 full links (inie and outie) needs to be replaced.
Replacing chains when needed will allow the cassette and chainrings to
last longer -- since they cost considerably more than a chain, this is
good. When you replace the chain, if it "skips" under load, slipping
off the sprocket under pressure, especially in your favorite gear, then
the cassette, or at least that sprocket, needs to be replaced. Replace
the chain when the teeth get sharpened like shark's teeth, or when they
are so thin that some of them bend or break.

Most parts need to be periodically checked for cracks. Bearings, like
bottom bracket and hubs, will need work when they make noise or run
rough. Hubs usually are serviceable, bottom brackets are usually not
these days, but are cheap to replace. Same goes for headsets, but they
last longer. Ditto pedals. maintenance (greasing) will make a big
difference with most pedals, and re-packing (replacing grease and
bearings, along with thorough cleaning) is needed for hubs and any other
servicaable bearings. Brake pads wear, and need replacing when they get
too thin. Similarly, rims wear for the same reason, and do need
occasional replacing, but that will take thousands of miles, depending
upon riding conditions.

If your bike creaks or clicks, check it out. That can be a crack
developing.

--

David L. Johnson

Accept risk. Accept responsibility. Put a lawyer out of business.

Aside from tires what other parts are prone to wear out over time and
at what rate?
I am suspecting eventually the chain will go along and later the crank
and the cassette. But what's a typical mileage number assuming a
decently maintained bike?

Chains on road bikes- 1000-4000 miles, depending upon rider weight, terrain
(hills wear chains out more quickly), and especially how clean/dirty it is.
Rain kills drivetrain components (and many others).

Cassettes- If you replace the chain before it gets too bad, you'll get 5
chains to 1 cassette. Chainring wear is dependent upon "sophistication" (how
much weird machining is involved to make it shift better, which also causes
them to wear out more quickly) as well as the same things that wear out
chains. In the old days, we rarely saw chainrings wear out so badly that
chains would slip on them. Now, it's very common to see middle chainrings on
triples that have worn such so much that they slip.

Rims- Who know? Older heavy aero-type rims would bust a curb before they'd
break or dent. 30,000+ miles was not uncommon. Modern lighter rims will
typically go from 7-15,000 miles on the rear. Front rims don't wear out from
miles per se, but riding in the rain will wear out the sidewalls such that
they'll liteally explode outward at some point. That point can be as few as
2000 miles in some cases, depending upon how mucky your ride is and how much
you have to use your brakes. You're basically talking about taking sandpaper
to the sides of your rims under such conditions.

Handlebars- Nobody replaces handlebars as often as they should (including
yours truly). In my opinion, 20,000 miles (assuming no crashes) is probably
a good time to be thinking they ought to be replaced. A failed handlebar can
wreck your day.

Gear cables- For STI road levers, 7-12k miles is common for failure. This is
one of the most-ignored maintenance items, because you don't see the problem
(caused by the very tight radius the cable follows inside the lever), and
the only symptom of a cable needing replacement happens just before it fails
(you'll be able to shift to a larger cog, but it won't want to come back
down to a smaller one).

Brake cables- Everyone worries about brake cables, but they rarely fail. No
tight bends. Use common sense; if you see a lot of corrosion, go ahead and
replace them. But generally, if things are running smoothly, you can go a
very long time before worrying about them.

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA


"Jorg Lueke" wrote in message
oups.com...
Aside from tires what other parts are prone to wear out over time and
at what rate?
I am suspecting eventually the chain will go along and later the crank
and the cassette. But what's a typical mileage number assuming a
decently maintained bike?

Thanks for the replies that's very helpful to know.

On Fri, 21 Sep 2007 23:46:44 -0400, "David L. Johnson"
wrote:

Of course every part is subject to wear, or fatigue. Chains would be
the next in line after tires.

On my (road) bikes, tyres last longer than chains. I change the
chains on two Campagnolo 10 speed transmissions every 2,000km. There
is still some margin, but I prefer to replace the chains rather than
the rear cassette. Tyres last at least 4-5 thousand km.

Nice summary, Mike -- I'm going to print it out and keep it in my
maintenance stack in the garage.


-JR

Mike Jacoubowsky wrote:

Brake cables- Everyone worries about brake cables, but they rarely fail. No
tight bends. Use common sense; if you see a lot of corrosion, go ahead and
replace them. But generally, if things are running smoothly, you can go a
very long time before worrying about them.

I've never had a brake cable fail, but I have had my cantilever brakes
straddle cable fail a couple times. Both after about 20,000 miles. So,
it's probably better to change them more often than that.

--
Dane Buson -
WARNING TO ALL PERSONNEL:

Firings will continue until morale improves.

In article ,
Dane Buson writes:
Mike Jacoubowsky wrote:

Brake cables- Everyone worries about brake cables, but they rarely fail. No
tight bends. Use common sense; if you see a lot of corrosion, go ahead and
replace them. But generally, if things are running smoothly, you can go a
very long time before worrying about them.

I've never had a brake cable fail,

I /have/.

I had the lead nub that goes inside the brake lever, pull
off of my front brake cable while coming home from
Spanish Banks. As I recall it was on the Off-Broadway
bike route, just before Cypress or Maple St. An elderly
bald gent pedestrian thought it was weird that I'd pull-off
the street to apparently yield to the cross-street traffic who
had the stop sign. Then I had to explain my conundrum to him.
He was a nice guy. To this day I recall how the sunlight
glistened off his well-tanned scalp.

but I have had my cantilever brakes
straddle cable fail a couple times. Both after about 20,000 miles. So,
it's probably better to change them more often than that.

I've heard horror stories of front inner cables failing,
causing old-school MTB canti straddle cables to fall onto
and get caught in the front tire's knobbies. I guess that's
why V-brakes are so popular. Remember when MTBs came equipped
with that hook thing on the front brake-bolt to catch the
straddle cable in case that happened? Fenders work just as well.


cheers,
Tom

--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca

On Sep 23, 10:00 am, Dane Buson wrote:
Mike Jacoubowsky wrote:

Brake cables- Everyone worries about brake cables, but they rarely fail. No
tight bends. Use common sense; if you see a lot of corrosion, go ahead and
replace them. But generally, if things are running smoothly, you can go a
very long time before worrying about them.

I've never had a brake cable fail...

I've had two of them fail in the past 35 years, one being on our
tandem. Neither was a major problem, actually. Both were towards the
end of the day's ride, and I simply braked earlier using the other
brake.

I've thought about this a bit. ISTM that almost all my braking is
really very gentle. And of course, I try not to waste energy by
unnecessary braking. That includes downhills, where I usually
outcoast my riding partners. But in any case, "emergency" braking, or
hard braking of any kind, is really rare for me.

Back when I rode my mountain bikes a fair amount, it was different. It
would also be different if I did any racing, I suppose. But my
utility, day riding and touring don't seem to demand much from my
brakes.

- Frank Krygowski

Mike Jacoubowsky wrote:

Brake cables- Everyone worries about brake cables, but they rarely fail. No
tight bends. Use common sense; if you see a lot of corrosion, go ahead and
replace them. But generally, if things are running smoothly, you can go a
very long time before worrying about them.

In college, I was riding down a fairly steep hill on campus, in the
winter, and a brake cable snapped. No problem, so I thought... until the
other one snapped as well. I think it must have been related to the cold
snap, this was in northern Florida and sub-freezing weather was pretty
rare. The cables were probably about two years old. There was no visible
corrosion at all.

I was able to do a foot stop at the bottom of the hill.