Chain falling off smallest chainring when shifting to lowest gear

[Clueless in Seattle]

I'm an old guy with a failing heart, so I often have to shift to my lowest gear when trying to get up the steep hills in and around Seattle. And more often than not, when I shift the forward derailleur down, the chain overshoots the smallest chainring, and drops between the frame and the chainring, sometimes getting lodged there.

But if I adjust the little set screw to prevent this from happening, then the chain won't shift down to the smallest chainring at all.

Is there anything I can do to prevent this from happening?

Will in Seattle
a.k.a. "Clueless"

P.S. The autocorrect wants me to type "chain ring" instead of "chainring."

 

[Cycleops]

Put the chain on the biggest rear sprocket, then inspect the front derailleur to check the inner gap is as small as possible by adjusting the L screw. You may need to slacken off the cable with the barrell adjuster a bit.
Sounds like you may be confusing the L and H set screws.
Rather than go through the process take a look at the Park Tools video which explains it very well:

View: https://youtu.be/ZNG7g83lI-s

 

[Smokin Joe]

Fit a chain catcher in addition yo getting correct adjustment -

Deda Elementi Men's Dog Fang Chain Catcher, Black, 34.9mm 8051406523268 | eBay

 

[I like Skol]

Fit a chain catcher in addition yo getting correct adjustment -

Deda Elementi Men's Dog Fang Chain Catcher, Black, 34.9mm 8051406523268 | eBay

Chain catcher should not be necessary if the front mech is positioned correctly (i.e parallel to the chainrings).
Cyclops almost has the correct procedure so is a good starting point.

 

[Tigerbiten]

I agree that chain catchers shouldn't be necessary.
But some setups are more susceptible to dropping chains than others.
This one sounds like one.
So after tweaking to see if I can stop it happening, I'd probably fit one anyway for peace of mind.

Luck ............

 

[Smokin Joe]

Chain catcher should not be necessary if the front mech is positioned correctly (i.e parallel to the chainrings).
Cyclops almost has the correct procedure so is a good starting point.

Pro teams fit them, so they'll do for me. However well the front mech is adjusted, hit a bump mid shift and the chain can drop.

 

[Clueless in Seattle]

Sounds like you may be confusing the L and H set screws.

I think you may be right, Cycleops. Thanks for that video.

 

[fossyant]

I have the dog fang on both my road bikes as a 'just in case' to protect the paint, if nothing else.

 

[yello]

There's nothing wrong with a bit of 'just in case'. I'd like to think my derailleurs are correctly adjusted but even so I'll still get the odd chain drop, particularly if I shift too many in one hit.

 

[boydj]

Drop to the small chainring while you still have a few gears to go at the back. This will keep the chainline straighter and the chain less likely to come off. And fit a dog fang or similar.

 

[Clueless in Seattle]

Hi, Boydj, Thanks for the tip about leaving the rear derailleur a few gears above the lowest gear. I had been experimenting with that trick before posting here, and sometimes it seemed to work. But the trouble was that doing that required me to think ahead when approaching an uphill climb. And I'm such a daydreamer when I'm out riding my bike that by the time I remembered to check the rear derailleur I had already down shifted the front derailleur and heard that sickening "clunk" as the chain dropped off yet again.

I think the solution for me, since I'm such a space cadet, is to have a chain catcher installed when I take my bike into the shop for its annual tune-up.

So, that brings up the question of which brand to ask for. Are all chain catchers created equal? Or is there a clear consensus on which brand stands out from the rest?

Will in Seattle
a.k.a. "Clueless"

 

[Clueless in Seattle]

Hi, Boydj, Thanks for the tip about leaving the rear derailleur a few gears above the lowest gear. I had been experimenting with that trick before posting here, and sometimes it seemed to work. But the trouble was that doing that required me to think ahead when approaching an uphill climb. And I'm such a daydreamer when I'm out riding my bike that by the time I remembered to check the rear derailleur I had already down shifted the front derailleur and heard that sickening "clunk" as the chain dropped off yet again.

I think the solution for me, since I'm such a space cadet, is to have a chain catcher installed when I take my bike into the shop for its annual tune-up.

So, that brings up the question of which brand to ask for. Are all chain catchers created equal? Or is there a clear consensus on which brand stands out from the rest?

Will in Seattle
a.k.a. "Clueless"

P.S. I'm thinking of ordering the dog fang from amazon.com. How do I know which size to order? My bike is a 1990s Specialized Hardrock.

 

[boydj]

You need to check the spec of your bike for the diameter of the seat tube to determine which size you need. There's not much difference between different makes. Pop into a local bike shop and they should be able to sell you the right size, rather than going to Amazon.