peugeot mongrel

I'm afraid I've never seen this on a frame. Can anyone tell me what it is for.

cb400bill

It is a place to hang the chain when you have to remove the rear wheel.

norskagent

That is just for hanging your chain, when you do a wheel change or repair. LATE!

k_as_in_knife

What they said; I'll just add you want to be sure you remember to take the chain off the hanger before you ride away

sauze

Ha weirdly enough I was cleaning my winter bike and noticed this little piece as well. Great to know!

spock

Great invention. I don't know why they uninvented it.

That's actually pretty useful when on the go.

One time I came into the LBS without the rear wheel to change the chain with my old chain on bike and on the hanger. Mechanic put the bike on the stand and started doing his thing. Then he went, "I see why you wanna change it. It's very stiff". I couldn't believe it. I just thought that bike mechanics are supposed to know these things.

anastrophe

My LHT has one and it is just amazing. Funny how a little thing can make a real difference.

Chombi

Unfortunately, it pretty much dissapeared with CF bikes. Maybe CF frame disigners wanted to minimize any interruption to the CF material on seat stays. It's really a hassle everytime I take off the rear wheel on my Vitus Carbone and the chain just wants to just fall down on the ground and possibly scratch up my drive side chainstay. You also end up trying to spin the jockey wheel cage back into position after it turns counterclockwise when the chain tesion is released and wrap itself with the chain. Doing all this plus holding up the chain to catch the cogs correctly with the chain when reinstalling a rear wheel is a royal PITA!

Chombi

eddubal

Just don't do what I did and forget to pull the chain off it when you ride. It's a great way to lose it...

Spookeay Bird

Really? and I thought is was just a totally cool way to ride with the chain up high. Yea Man!

greyghost_6

I thought that's where you were supposed to hang your car keys so you can be all like "8itch, I don't need no car keys!"

unterhausen

it hasn't been uninvented, but you aren't going to see it on many production bikes. I prefer the Columbine chain hangar because it's passive, just shift into high gear

spock

Yes it was. I can show you the uninvention patent.

But you correct. Not used much any more.

Wogster

They can't put those on Carbon bikes, it increases the weight by a whole .1g and we all know that such a massive amount of weight should never be voluntarily added to a CF frame bicycle
Of course with a 10kg bicycle, like was common in the old steel days, that was considered nothing, so they brazed them on.. I'm wondering though, if you had something like a plastic light bracket from an old light that fell off after hitting a pothole last week, you dremel the bracket off short so there is only about 6mm left, and wrap that around the stay, if it wouldn't be fine for the same function.

Zaphod Beeblebrox 

as long as the chain tension doesn't break your plastic nubbin I'd say yes.

OP: What kind of bike is that?

sauze

Coppi? I glean this only from the img name.

JohnDThompson 

Trek put them on thousands of frames in the early 80s. The Trek investment cast dropouts used in the mid-80s had the hanger cast into the dropout socket.

SJX426 

My 97 RockHopper has one and I forget to use it 'cause it is the only bike with one!

michaeldaruwala

Just to add to your information, plastic chain holders were available. They had a tensioned plastic clip that pressed onto the rear stay. A touch of glue, was additional protection to keep them in place.