Singlespeed & Fixed Gear - dang chain fell off!

so i'm gliding down a hill on my SS, hop off a curb, give it about three hard pedals... and suddenly, i feel all the resistance disappear. i look down, and lo & behold, i'm transported back to my old schwinn mtb days: the chain just sort of fell off. luckily it didn't bind up the chainring or anything; i coasted to a stop and slid the chain back on, rode home like nothing happened.

so the question is, wha' happened? i know my chainline isn't perfect, but it's close (the cog needs to be spaced about 5mm more away from the hub). i didn't check the tension before i left, but i'm fairly confident my rear wheel didn't slip forward while the thing was locked up. i'm assuming this could be a result of the little curb hop... what am i doing wrong? anybody had this same experience?

Get those red chain tensioners that go around the chain ring. They are made for people with bad crazies like yourself.

you mean like on a downhill mtb? that'd be kind of cool... not sure i'm that hardcore on my road bike tho................ ;)

5mm off is a lot for chainline, it's enough to pop off easily.

hmmm................ maybe i should address that issue

I don't know what you did wrong, but you should clearly make an fashion accessory out of your old chain. A necklace? A bracelet?... I don't know. The choice is yours. But you must do it. And do it now!

the old chain's gonna be a necklacke... i'll hang a big fake gold plated pot leaf from it. big, like 8" across... yeah, then i'll be pimpin' it...

the old chain's gonna be a necklacke... i'll hang a big fake gold plated pot leaf from it. big, like 8" across... yeah, then i'll be pimpin' it...


Whoa, dude, I was only kidding!

what sort of chainring is it?

shimano 42t... don't know the exact model, no ramps tho.... sounds like chainline may be the problem. what's the best way to check that it's correct?

I don't know what you did wrong, but you should clearly make an fashion accessory out of your old chain. A necklace? A bracelet?... I don't know. The choice is yours. But you must do it. And do it now!

I've got the track chain bracelets goin on. But they're from leftover chain, not used chain. Looks better.

Gotta few little scars on the inside of my wrist from the last wreck, too.

How's that for being a posenger?

Add to your 5mm of your chainline offness the flex of your chainstays during heavy loads and you've got yourself a derailled chain. Get your chainline straight and all should be well. Also make sure you've got good chain tension and all will be well.