New Granny chainring
#27
Senior Member



Joined: Aug 2010
Posts: 12,760
Likes: 2,117
From: Madison, WI
Bikes: 1961 Ideor, 1966 Perfekt 3 Speed AB Hub, 1994 Bridgestone MB-6, 2006 Airnimal Joey, 2009 Thorn Sherpa, 2013 Thorn Nomad MkII, 2015 VO Pass Hunter, 2017 Lynskey Backroad, 2017 Raleigh Gran Prix, 1980s Bianchi Mixte on a trainer. Others are now gone.
For those bikes that have a front derailleur mount on the seat tube that the derailleur directly bolts to instead of using a circular clamp to hold the derailleur to the seat tube, they make some rather expensive chain catchers that bolt directly to that frame mounted fitting.
The graphic below is a copy I saved to my hard drive in 2011, I saw this in an article about bikes at a race and it said that some mechanic apparently dreamed up a chain catcher that was made from a stiff piece of wire or maybe a small diameter rod. A friend of mine had a bike with that type of front derailleur mount, so I saved that graphic at that time to show him.

It was very soon after that when a wide variety of expensive ones appeared on the market that served the same exact purpose as that piece of stiff wire. (Perhaps that mechanic should have patented his invention?)
If your seat tube is not circular or an unusual larger size, that could be another option if you have that frame mounted fitting to mount the derailleur to.
The graphic below is a copy I saved to my hard drive in 2011, I saw this in an article about bikes at a race and it said that some mechanic apparently dreamed up a chain catcher that was made from a stiff piece of wire or maybe a small diameter rod. A friend of mine had a bike with that type of front derailleur mount, so I saved that graphic at that time to show him.

It was very soon after that when a wide variety of expensive ones appeared on the market that served the same exact purpose as that piece of stiff wire. (Perhaps that mechanic should have patented his invention?)
If your seat tube is not circular or an unusual larger size, that could be another option if you have that frame mounted fitting to mount the derailleur to.
#29
Bikes are okay, I guess.



Joined: Jan 2015
Posts: 8,058
Likes: 3,822
From: Richmond, Virginia
Bikes: Waterford Paramount Touring, Raleigh Sports 3-speeds in M23 & L23, Schwinn Cimarron oddball build, Marin Palisades Trail dropbar conversion, Nishiki Cresta GT, Jeunet mixte
I call this my K-Mart triple, a Sugino Maxy 34/45 with a 22T cog from a SunTour Perfect freewheel, combined with a 34T large cog gives a 19" low. I chose this as the smallest ring with holes in a multiple of 5 to fit this crank. You might apply the same thinking to a four-arm crank.
#30
Thread Starter
aka Timi

Joined: Feb 2009
Posts: 3,611
Likes: 327
From: Gothenburg, Sweden
Bikes: Bianchi Lupo & Bianchi Volpe Disc: touring. Bianchi Volpe: commuting
#31
Senior Member

Joined: Jul 2010
Posts: 13,928
Likes: 1,243
From: Montreal Canada
Make sure the FD inner limit screw is set so it's just, just past rubbing the chain on the biggest cog and then see how quick downshifts go (in case you need to get a chain catcher gizmo)




