Severian

So here's the issue that's been jogging around my mind for a bit:

WHEN should parts be replaced? I've heard of people replacing chains anywhere between 1000 and 2000 miles. Wheelsets and suchlike every 5000 miles. Brake pads when they get worn. Cables when they get stretched past the ability of a mechanic to tune them. So and and so forth..


what is YOUR preferred replacement schedule?

operator

People need to stop treating their bike like a car. If a chain hasn't stretched (measure with a ruler or a chain checker) past 1/8" (or less) then you don't need to replace it.

Anyone advocating replacing a chain at x miles needs to have the rest of their advice ignored.

I have heard of no such metric.

Duh.

I've never seen a cable stretch beyond adjustment. Anyone providing a set number to any of your questions is suspect and their advice needs to be thrown out.

Do periodic maintenance check on your components, if something needs to be replaced, replace it. You can't say after x miles component y automatically fails and must be replaced.

moxfyre

Very true. I think that chains *might* be an exception, since they are cheap enough and affect enough other parts that it might be worth replacing them early just to be safe.

For example, my chain has about 3000 miles on it and is still at 12-1/32" (only 0.25% elongation), but I figure I might as well replace it since this chain probably wears out the cogs slightly faster than a brand new one, even if it isn't much. And plus I have about 5 Nashbar chains I've ordered to bump myself over the $75 mark or whatever, and haven't yet used

Portis

Parts should be replaced when they NEED to be replaced. When, varies a great deal from bike to bike, rider to rider, and because of lots of other variables like road conditions, maintenance schedule, etc.
Just assigning X number of miles is impossible.

HillRider

Get your popcorn and cold drinks ready, this is going to be a looooong thread.

bkaapcke

Often I replace parts when I want to upgrade them. Cassettes, chains, chainrings, derailleurs, tires etc. Yeah, they are usually not worn out, but who cares? bk

Portis

Nobody has mentioned chain lube yet...

erader

after a while you'll know about when a chain needs to be replaced. it was about every 2k miles when i was riding hard and climbing alot. so i changed my chain every 2k miles and sometimes a cog or two if needed.

ed rader

erader

if YOU cared you could probably save a buck or two

ed rader

erader

dry lube is for guys with very low standards

ed rader

Bobby Lex

How often do you empty your bowels?

Bob

Severian

Good question... when I feel the need.

Which dovetales nicely into an alteration of my post...

Using the example of a wheelset... under what conditions of wear would YOU replace a wheel? We've seen cracked rims, bent spokes, broken flanges, bent and gougued braking surfaces (on the rims)... what is the absolute minimum and maximum amounts of allowable wear on a wheel?

well?

Pete Hamer

Let's not forget about stems, handlebars, forks, seatposts, frames, etc. Non-moving parts have finite fatigue lifes and will break if used for too long, especially very light weight aluminum, scandium, and magnesium parts. The stress acrued from crashes can shorten the normal fatigue life of these parts. I'd rather replace a handlebar at a scheduled interval rather than wait for it to break. For lightweight aluminum or magnesium parts that are part of the steering system I'll replace about every two years if they have high miles (2,000-4,000 a year primarily off road). Once a year if crashed. I don't ride on steering system parts if I see signs of damage.

I replace ball bearings around 3,000 miles even if there are no symptoms of wear or damage. I'd replace a wheel after the second or third JRA broken spoke.

Rims are now coming with wear indicators. Disc brake rotors are coming with minimum thickness specifications. I whole hartedly support these ideas.

My conclusion; Replace steering system parts every couple years if riding frequently or racing. Replace ball bearings in cup and cone systems every 3,000 miles or less . Replace other parts as symptoms dictate or when specified wear limit is reached.

roccobike

Anyone changing their wheels at 4000-5000 miles should mail them to me for proper disposal.

capwater

To quote our late, great Sydney Boudreaux .... "How long is a rope?"

I do have a great friend who changes his tubes on a set mileage basis. Hey Joe, sorry piasan, but you can always give them to me!!!!!

Bobby Lex

There's your answer. Not according to a set "replacement schedule".

Bob

Pete Hamer

The people riding these parts probably wish they had replaced them them according to a set "replacement schedule".

https://pardo.net/bike/pic/fail-009/000.html


"Yet another fatigue failure in a bicycle crank spider arm. This was a high quality component that had very high load cycles but was in excellent apparent condition until the final fracture that unseated the rider in heavy city traffic. Fortunately no long term injury occurred."

John E

Having snapped a Sugino crank at the pedal eye during an out-of-saddle climb, and having cracked a cottered steel crank at the cotter eye whilst accelerating across a busy intersection, I do believe in replacing safety-critical parts periodically. I have also snapped two rear axles, one hollow/QR, the other solid, and I have broken one (Nishiki Competition) frame at the BB shell and another (Peugeot UO-8) at the right chainstay between the clearance dimples, but none of these failures were dangerous.

For chains, I use Sheldon Brown's 1/2 percent elongation rule.

Severian

well haven't I just cracked open a can of worms...

like the man said.. need might be on a commute (as it would be for me) in the middle of traffic at speed.

capwater

You should replace all your parts every 6 months to ensure nothing ever breaks unexpectedly. Oh yeah, send the old stuff to me.....

Chains are about the only thing you can quantifiably measure for wear. Headsets you can tell by feel. Most everything else is too tough to determine until it actually goes teats up..

humble_biker

All of the above except for the bent spokes are life threatening or serious injury producing. Ever seen a side wall on a rim exploded from brake pads wearing through the rim? I have and lucky for the owners they were just changing a tube and not riding when it has happened.

wroomwroomoops

I agree completely.

However, I am usually unable to determine whether my cassette needs to be replaced or not, unless it's really worn out bad.


Thechnically, if one is healthy, they have a regular daily schedule, and perform the duty roughly at the same time. For me this is in the morning, so I usually just sit on the "throne" even before any urge, and "just do it".