Shortest time/lifespan of a new component on your bike
 

I recently had to replace my rear tyre after 1,700+km. For me, I was disappointed to be replacing a new tyre after such a short period of time. So this started me thinking on my ride today...

What is the shortest amount of time you've have a new component on your bike before you've had to replace it. The component could be a new tyre that you rode for 200k before getting a gash in the side wall. Or it would be a new water bottle that you put in your cage, then smoked a pothole after 15k only to see the water bottle go flying where you couldn't retrieve it.

Inner tubes don't count. Curious to hear your stories.

Replaced not by choice: I had a 700x35 Panaracer Gravelking SK blow a 6" long gash in it's sidewall with all of about 160 miles on it. Replaced as defective under warranty.
Replaced by choice: my R3 came OEM with Mavic Aksium Elites and 700x25 Mavic Aksions. Horrible. Awful. I knew after the first day they had to go. They came off of the bike at 130 miles, and were sold immediately. I only rode them for 130 miles because I was waiting for the replacement wheels to arrive.

I also benched a Fabric Line Elite saddle after just 154 miles. I tried. It still hangs on a hook.

I took the valve caps off 1 second after I looked at them

I always replace the saddle right away. Handlebars too and stem.

SAME HERE, and then I put a white cap on the front and a green cap on the rear.

I did one ride on a brand new set of GP4Ks and the rear tire had a sidewall failure at the 150 mile mark (ride was 207 miles total). I booted it with a clif bar wrapper and finished the ride but that was the second time I've had a premature failure with those tires so I'm gonna stop buying them.

I removed my bell after three rides. It was so much fun to ring, I couldn't resist giving a ding at the tops of climbs or when rolling out after a regroup. Figured I might be annoying my riding buddies so I took it off. :o

I pulled off the dork disc before the first ride on my 2013 Madone.

Aside from the frame, fork and wheelset, you can pretty much chuck everything else on a bikesdirect Windsor Clockwork right into the trash.
Had the headset fail maybe three days after I got it put together.

Bar end cap. I never even got it on the bike. I was putting on new bar tape and set the end cap on the floor. My pack rat of a cat grabbed it and ran to the other end of the house. I searched the room he came out of for a few weeks before buying another cap. I finally found it in a different room 8 months later. Black end cap was in the coils of a black extension cord. I miss that cat.

Dork disc, reflectors, warning labeling, valve stem caps and stock pedals. I would not even bring the bike home until its off the bike!

Video camera mounts. Handlebar mount nuts and bolts weren't captive like my other mount, lost 'em immediately in the dark. And the helmet mount broke on the second use. Most mounts included with low priced video cameras are crap so I wasn't surprised. I always use backup lanyards for video cameras because the mounts are so bad.

Wahoo Fitness ANT+ case for my iPhone -- USB port broke within a couple of days. Same with Mophie Juice Pair Air. So I have to remove the phone from both devices to recharge it through the original Apple cable. Makers of otherwise useful doodads for iPhones can't seem to put together decent USB ports, so the entire device is basically crippled by a single cheap component.

Rubber band mounts, whether OEM with the light or other device, or aftermarket rubber bands. About half fail on the first use. Most fail after a few uses. I switched to rubber block/velcro strap type mounts like the Two-Fish for my Light & Motion Urban light. And use backup lanyards for anything that's expensive to replace.

With tires, so far, so good. I avoid tires with too many user reports of sidewall failure. I can deal with puncture flats -- that's so variable according to riding conditions. But sidewall failures? Nah. Unless we're riding through an obstacle course with razor blades at curb level, that should never happen. I've had good luck with Conti's cheap Ultra Sport II tires. Can't see paying more for GP4ks and GP5k with the reports of premature failure. I'm not strong enough to take advantage of a couple of watts difference. I rode Schwalbe One V-Guards for a year and while they were nice tires they cut way too easily. Not many puncture flats, but they cut like Henry Cooper's face under Muhammad Ali's gloves. Had to retire those Schwalbe's long before the tread was worn out.

Hybrid: reflectors and warning stickers (day of purchase)

Road: stem (couple months after purchase when I did the fitting after putting some miles on it as-delivered from the factory to see what was working and what wasn't)

Whats called the "Dork disc" doesn't bother me but the wheel reflectors went once I got the bike home. As far as real parts, the stem went after about 50 miles along with the saddle. A lot since then but the real issue came when a driver cut me off on a traffic circle and I had to lock up the brakes, hand slipped off the front brake lever and flat spotted the rear tire and dumped the bike on the right side. Thankfully I had my right forearm out to protect my bike and it, the bike, did not get a mark on it. Can't say that for my arm but I will heal, advantually.
Frank.

I bought my bicycle in May and the only original parts that remain are the head set, brake calipers, and seat post bolt.
Seat and crankset were the first to go; I believe they were changed out on the first day.

Not quite "had to replace" but:

Twenty years or so ago I bought a new Trek 520 touring bike. On my second ride, the rear wheel turned into a taco, with many, many spokes loosening up. Brought it back to the bike shop, they said "Oh yeah, these machine built wheels always have that happen," trued the wheel and I went twenty years without problems and then finally broke a spoke. Never had that happen before or since.

The component I've had fail that I'm not impressed with are the Bontrager rubber cadence sensor magnet bands that go on your crank if you use the DuoTrap built in sensor on a Trek bike. I had two split very quickly, plus it doesn't stay in place very well - just zip tied it in finally.

About 2000 miles for each of the first two rear wheels on my Trek Domane 4.3. Second warranty replacement resulted in a (free) upgrade to a Paradigm wheel . . . but haven't hit 2k on it yet.

[CAN OF WORMS]

I had a Brooks B-17 for a little less than a month. It got wet at the start of a 100-mile gravel race and by the end had deformed into a mishapen ass-hatchet that was unrideable. And yes, I had used proofhide.

It's been a $130 waste of space in my parts bin ever since.

[/CAN OF WORMS]