Derailleur spring tension help
05-27-13, 06:24 PM
#1
Full Member
Thread Starter
Derailleur spring tension help
Was doing a ride yesterday when some kid in front thought going down hill would be a great time to practice skin whips, crashed, and took a bunch of us with it. I was fine as I chose to just grind a curb rather than pile up. Continuing the ride, my derailleur lost tension and I thought it was wrecked, but it turns out I just lost the circlip somehow and it came started to come apart. Not at the 'top' where it bolts to the frame, but at the bottom where the metal pieces that hold the wheels connects. Sorry, I don't really know the terminology.
It seemed simple enough to put back together, but I don't get it, it has no tension. I put the spring ends into the holes and put it together, but it has no tension. Spring is fine, derailleur is fine and not bent or broken anywhere, I just don't know how to get tension. I figure I have to wound the spring, but how? Is it as simple as turning the derailleur over itself (but what keeps it from bouncing back?). Any resources would be helpful. Thanks!
It seemed simple enough to put back together, but I don't get it, it has no tension. I put the spring ends into the holes and put it together, but it has no tension. Spring is fine, derailleur is fine and not bent or broken anywhere, I just don't know how to get tension. I figure I have to wound the spring, but how? Is it as simple as turning the derailleur over itself (but what keeps it from bouncing back?). Any resources would be helpful. Thanks!
05-27-13, 06:37 PM
#2
Senior Member
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,724
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Mentioned: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5791 Post(s)
Liked 2,581 Times
in
1,431 Posts
Sorry to hear your derailleur is suffering from limp spring syndrome. This sometimes happens with age, or after a trauma. Unfortunately they don't make little blue pills for this so you'll need to fix it yourself.
The pulley "cage" needs to be wound back (counter-clockwise)one turn to load the spring. However RD cages have a stop pin to keep them from unwinding, so you have to remove it if it comes off. Or on other models with a fixed stop pin, you need to remove the circlip, or loosen the lower pivot bolt enough yo ease the cage out from the body until the pin clears, then wind it back and trap it with the spring loaded.
Either way the principle is the same as any spring driven device, you wind back to load the spring.
BTW- some RDs have multiple holes to accept the spring, giving you some choice about tension, but whatever hole you use, you still have to load the spring.
The pulley "cage" needs to be wound back (counter-clockwise)one turn to load the spring. However RD cages have a stop pin to keep them from unwinding, so you have to remove it if it comes off. Or on other models with a fixed stop pin, you need to remove the circlip, or loosen the lower pivot bolt enough yo ease the cage out from the body until the pin clears, then wind it back and trap it with the spring loaded.
Either way the principle is the same as any spring driven device, you wind back to load the spring.
BTW- some RDs have multiple holes to accept the spring, giving you some choice about tension, but whatever hole you use, you still have to load the spring.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
05-27-13, 06:49 PM
#3
Senior Member
Join Date: May 2010
Location: Bastrop Texas
Posts: 4,480
Bikes: Univega, Peu P6, Peu PR-10, Ted Williams, Peu UO-8, Peu UO-18 Mixte, Peu Dolomites
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 967 Post(s)
Liked 1,629 Times
in
1,045 Posts
Same thing happened to me on a cheap derailuer - Never did get it back right - If your successful in your fix please post pics...
Thread
Thread Starter
Forum
Replies
Last Post
davester
Classic & Vintage
10
05-05-18 07:55 PM
