mschwett 

today i had a (semi-self-induced) mechanical in an area without cell service, and didn't have the quick-link pliers needed to resolve it. was hammering a descent pretty hard (for me), approx 40mph and 750w, when i saw a car on a crossing road that honestly i've never seen a car on in 100+ rides. i had the right of way, no stop sign my way, no light, no yield, and the car wasn't moving, but it surprised me and i abruptly let off the pedals and may have even backpedaled a bit. next thing i know, chain is strangely jammed. rolled off to take a look at it and found the chain between the little ring and the chainstay, all the way up against the bottom bracket. clearance between the little ring and the chainstay is way less than the thickness of the chain, at least without serious force which nobody who saw the problem thought it wise to apply. i assume while riding hard, that area is flexing in ways that increased the clearance, plus the rotational force and perhaps very good timing of the chain plate geometry and it slipped in there.

figured, whatever, i'll walk a few miles to where there is service (it's just a smallish pocket of no service, not even far from the city) and get an uberXL for the short ride of shame to a shop or home, either within 5 miles or so.

this is a popular riding route, and perhaps 20 to 30 other riders passed in the next 5 to 10 minutes, and the vast majority, if not every single one offered to help. a group of 6 or 7 didn't have the chain pliers but thought they might be able to resolve otherwise, but couldn't. another couple inquiries later and a very nice, very thoughtful, mechanically skilled guy on a gravel bike had a plastic type of detachable chain plier that i haven't seen, which popped open the quick link no problem, chain out, back in correct routing, back together in a few minutes. he was super helpful, just like everyone else before him tried to be.

this was mile 11 of a planned 50-60 mile route, and i was very happy to continue. can't wait to pay it forward.

Polaris OBark

I now feel justified having that never-used Wolf-tooth chain pliers with spare quick-link in my saddle bag.

Most people around here are helpful (excluding a few in Boulder Creek who tried to kill us today).

wolfchild

That's why I always carry a small chain breaker and few inches of chain. If the quick link or any other link is damaged.... ( which is highly unlikely on a singlespeed) I could just remove the damaged chain link and install a new one with my chain tool and be on my way.

mschwett 

ironically, i also have such a tool… but after not needing it for the 10,000 miles since i got it, it was demoted to “rides >30 miles from home only” status. whoops

Koyote

Great story, I'm glad you shared it. This is why I carry more supplies than I think I'll need.

rsbob 

Get a chain keeper and it will never happen again.

rollagain

Back in the 90s when I was doing most of my own wrenching I learned that even a perfectly adjusted FD will still throw the chain sometimes. I equipped all my bikes with Third-Eye Chain-watchers. At the time, I didn't know of anyone else making a similar device; some other brands may be (likely are) easier to install.

But back to the topic, I've had a lot of positive experiences getting offers of help, and when I see someone else who looks like they're having mechanical trouble, I make sure to offer help.

ofajen

In a pinch, you can also use a shoelace to undo a quick link. Preferably a black one, I suppose.

Otto

RB1-luvr

It is so gratifying helping a stranger. I'm glad the OP had a nice experience.

KerryIrons

Even without a chain keeper it's not clear at all why this happened. Sounds like maybe an issue with the freehub that needs to be sorted out.

mschwett 

i spent quite a while staring at it trying to imagine the forces on the chain that would cause it to go where it did; all i can think of is backpedaling hard while in big little, the chain came off the bottom rear edge of the big ring (no derailleur to guide it there) and then was pulled inside and past the chainstay (which has about a half chains worth of clearance, no clue how) by the backpedaling since the rest of the big ring was still engaged with the chain.

it’s 12 speed di2 and has shifted flawlessly. the only chain drops ever have been backpedaling when stopped to get the pedal position where desired, but usually on the biggest rear cog, perhaps 2 or 3 times while stopped in 5,000+ miles.

KerryIrons

Is there maybe excess friction in the freehub such that when you backpedal it causes a lot of chain slack on the lower run of the chain? As a side note, most of the time when you reach speeds where you are spinning your biggest gear, you're likely going downhill and would be just as fast or faster to get into a tight tuck while you rest.

Inusuit

I was off the side of the road recently waiting for a break in traffic to take a leak. A car went by in the opposite direction, made a U-turn and stopped to ask if I needed help. It was an older woman. So some drivers are kind as well.

mschwett 

it spins very freely, or so it seems to me. doesn't produce any noticeable slack, but i'm no expert and will probably have the shop check it out.

the stretch in question is a very quick dip down and then back up (around 100' down at 8-10% and then a little uphill of about half as much after) which is quite straight so i do like to push it hard on both the downhill and uphill. i can't really remember if i actually backpedaled, or why i would have... but can't really think of another likely scenario.