Classic & Vintage - What does this screw do?

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Capecodder
06-30-11, 05:09 AM
This might be a dumb question, but what is this screw for? It is on the outside of the outter ring? If it were on the inside I would expect it to help the chan from the inner ring to the outter when shifting....

http://i131.photobucket.com/albums/p286/deerslayer1961/chainringscrew.jpg

rootboy
06-30-11, 05:24 AM
It might be reversed in its mounting hole. On the Campy ring, I always thought it was there to keep the chain from jamming down between the big and small rings. One of those safety things they forced Campy to add in, what, the mid 70's?
gearbasher
06-30-11, 06:14 AM
It goes behind the crank arm. It keeps the chain from jamming between the chainring and crankarm, in case of an overshift.

Bianchigirll
06-30-11, 06:53 AM
I agree it looks like a homemade replacement pin
BlueDevil63
06-30-11, 07:11 AM
It goes behind the crank arm. It keeps the chain from jamming between the chainring and crankarm, in case of an overshift.

+1
dbakl
06-30-11, 08:14 AM
Is there just one or do they go all the way around? If all around, I'd suggest a guard was bolted on.
ColonelJLloyd
06-30-11, 09:48 AM
It goes behind the crank arm. It keeps the chain from jamming between the chainring and crankarm, in case of an overshift.

+2
michael k
06-30-11, 11:23 AM
Adjustment screw...use it to realign the solar matrix of the chainring for maximum endothermic propulsion!
atmdad
06-30-11, 01:38 PM
Adjustment screw...use it to realign the solar matrix of the chainring for maximum endothermic propulsion!

Obsolete, remove it and go with an after market flux capacitor.
rootboy
06-30-11, 04:37 PM
It goes behind the crank arm. It keeps the chain from jamming between the chainring and crankarm, in case of an overshift.

yeah ...that's what I meant to say.:thumb:
jeepr
06-30-11, 04:50 PM
"What does this screw do?"


In it's current location, nothing except create interesting conversations.
rootboy
06-30-11, 06:17 PM
If that is the outboard side of the chainring, that is in the proper position.
Isn't it?
Capecodder
06-30-11, 06:19 PM
If that is the outboard side of the chainring, that is in the proper position.
Isn't it?

Yes.
rootboy
06-30-11, 06:25 PM
I'm trying to guess what brand that ring is. Stronglight?
bikingshearer
06-30-11, 06:31 PM
"What does this screw do?"


In it's current location, nothing except create interesting conversations.

It might also cause interesting nicks and abrasions to one's socks and/or ankles.
larwyn
06-30-11, 06:33 PM
Turning the screw will adjust the distance which it protudes from the chainring on both sides. Clockwise or anticlockwise, depending on where you are standing....................:D
rootboy
06-30-11, 06:38 PM
It might also cause interesting nicks and abrasions to one's socks and/or ankles.

only if they get between the crank arm and the ring :)
Capecodder
06-30-11, 06:40 PM
I'm trying to guess what brand that ring is. Stronglight?

Pretty darn good guess:thumb:
rootboy
06-30-11, 06:45 PM
I think I have one downstairs. I remembered the screw head. I have a Campy spare with that pin too, but it is fixed, not removable, as I remember.
Grand Bois
06-30-11, 07:36 PM
It's a ring for a Stronglight 93. It's mounted correctly and is an original part, not home made. The CPSC has nothing to do with it.

The Campy version is also removeable.
JohnDThompson
06-30-11, 08:37 PM
I'm trying to guess what brand that ring is. Stronglight?

That's what I'd guess as well.

That looks like an OEM Stronglight chain-drop pin.