Has this ever happened to you?



Fourth cog from the top. I was accelerating from an almost stop, turning left from a two lane onto a four lane, coming in from the down stroke of a T intersection. Had two full growlers (half gallon glass containers) of beer in the pannier, and I guess that I wasn't geared down far enough to accommodate the load and sudden acceleration (36t ring and 16t cog, unless I was in the big [40t] ring).

Made it past the first oncoming lane, then half way through the next lane when I felt the chain slip, hard. The pedals lost all resistance and dropped me flat-footed onto the ground, skidding on my shoes with the bike still rolling between my legs. I scurried back up into the saddle, shifted up, and pedaled away, unharmed beyond some slight skin loss on my left calf where the pedal impacted into the back of my Dickies.

I made it about a mile before I tried shifting back into the (as of yet unknown) damaged cog, only to find that the chain was slipping badly. I shrugged it off, thinking that I'd broken a few teeth, and rode home. It wasn't until I got the bike inside that I saw that 2/3rds of the 16t cog was gone.

Now I'm torn, as torn as a weak cog under load. Should I be proud that I tore my bike a new one? I'm definitely annoyed that I'll have to buy my bike a new one. Should I be angrier at myself for forgetting to shift down, or at SRAM for producing weak cogs (new at the end of April, it only has about 2000 miles on it). All that I do know is that I'm glad to have enough standover height on my bike to be able to drop both feet to the ground unexpectedly, and still be able to sing tenor.

But was the Beer safe? What kind of beer?

I have seen a whole cog break completely in half. Freaky isn't it?

You monster you!

no this does not happen to me!

Holy cow! No, nothing like this ever happened to me. How old was the cluster? Metal fatigue?

Isnt it a bit chilly up there?

is the gear hanger bent inwards?

Never experienced that YET !
I ride most of the time in the big wheel and in about 4 gears on the cassette....with about 80% of the time in one gear.....have found that I can only get about 6,000 miles (3 chains) on a cassette before the 80% gear is worn to the point that shifts start slipping.......just a bad habit on my part , I certainly know better than that....

DON'T LEAVE US HANGING!

Sheesh...who tells a story and leaves out the most important parts?

Your bike will not forget this insult. Repair the cog quickly. And get it a small upgrade of some kind.

+1

Has to be a manufacturing defect.

You're safe, and your bike isn't all that torn up. But c'mon... what about the beer? Glass containers? We'd hate to have to report you for abuse of alcohol by not drinking it.

It happened to me in 6th on a 7 speed cassette. It started during a left hand turn across 2 lanes of traffic by making some "something's breaking" sounds but got me through the turn. Next time I shifted to that gear there was more noise followed by less resistance pedaling, and when I stopped to see what was wrong half of the gear was left. It was on a Performance cassette, and they gave me a break on a Shimano cassette that's been fine for a few years.

Nothing anywhere near that bad. I've killed a few cogs by doing the same kind of thing, but it was a gradual death by comparison, and I didn't loose 2/3 of the teeth.

I'd get in touch with SRAM; maybe they'll replace it under warranty. Many bike parts are warranted for 1 year.


EDIT: BUT WHAT KIND OF BEER?

Wow I've broken all sorts of things on bikes but never a cog. Nicely done!

Yeah it does look like your derailleur hanger is bent as well. And wow ive never seen a cassette come apart like that, you beast

Hasn't happened to me. This had the potential to be a lot worse.

Glad you weren't hurt.

Ride safe,

Jeff

Tenors are squeaky wimps.

It happened because you have BB7's on there. I saw that red dial in the pic, oh I know it all too good. Since I installed my BB7's, I got multiple flats, chain skipping on a practically new cassette, and a lot of other funny things. But at least those BB7's work in rain and every other condition.

Yet, more manly than an alto

Y'all are hilarious! The beer was fine (thank Bacchus!). Better than fine, it was delicious: Prince William Porter from Moose's Tooth Brewery. They don't bottle, so if you want to try some, you'll just have to come on up here and get it. The other growler seems fine, but I'll be sure and test it tonight: Oatmeal Stout from Glacier Brewhouse, hands down the finest stout in town. Well, second only to their own Imperial Stout, which is aged in old oak Jim Beam barrels. Comes out smooth as silk, with a hint of chocolate, a little bit of smoke and whiskey, and finishing with a taste of licorice and a whole lot of sexy. It's such a beautiful beer that I get a beerection just thinking about it.

Agreed. I've done dumber stuff on the bike, full grocery loads from dead stops in too high of a gear, and all that usually happens is a bit of chainslip, followed by a bunch of mashing and cursing. I'll be contacting SRAM to see if I can get a replacement.

Or maybe it's this! I do have a new frameset, rear wheel, and various bicycle accoutrements ordered and in the mail, and I shall soon be retiring the Kona as the commuter/utility ride. Perhaps the Kona is upset?

Artifact of the camera. When it's in supermacro mode, it creates kind of a fisheye lens effect. Here's the derailleur hanger from straight on:

Is that what the mean by a cluster fruck?

Those brews sound tasty! Enjoy!

Wow! Can't say I've ever done anything remotely like this.... would need 3 of me to reef on a drivetrain that hard. I can't even break a spoke on my MTB.