rear derailleur cable
03-12-22, 06:38 AM
#1
Senior Member
Thread Starter
Join Date: Aug 2011
Posts: 554
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 198 Post(s)
Liked 52 Times
in
41 Posts
rear derailleur cable
how long should this be? the covering section of housing between the cable stop on the chainstay and derailleur cage? am changing from bar end to downtube levers. while removing the old cable, i noticed the housing noodle had worked its way out of the housing about 2"/ 52mm. the ferrule had opened or worn enough (i may have used a brake cable piece with larger opening not realizing) to allow the the noodle to pass.
because of this, my derailleur cable rubbed against the spiral housing and was down to about 3 strands. so it was just bulls... luck i took things apart before riding anyway.
Q: did the loop of cable & housing add to the problem? should i shorten it? or was it just normal wear? the cable was only 2 seasons old, and i ride less than 2k miles a season.
thanks
because of this, my derailleur cable rubbed against the spiral housing and was down to about 3 strands. so it was just bulls... luck i took things apart before riding anyway.
Q: did the loop of cable & housing add to the problem? should i shorten it? or was it just normal wear? the cable was only 2 seasons old, and i ride less than 2k miles a season.
thanks
03-12-22, 06:53 AM
#2
Newbie
Plase take a photo. It will be easier to even draw how it should look.
Cable length depends also from type of rear mech. Shimano with Shadow has much shorter outer cable than "standard".
Cable length depends also from type of rear mech. Shimano with Shadow has much shorter outer cable than "standard".
Likes For skom25:
03-12-22, 08:55 AM
#3
Senior Member
Join Date: Jan 2009
Location: San Diego, CA
Posts: 3,668
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 836 Post(s)
Liked 1,060 Times
in
744 Posts
+1 for photos and brand/model of derailleur would really help. Manufacturers usually post setup manuals online and will give a recommendation for housing loop length for your specific model. No way of knowing what caused your cable to fray without more info and usually not caused by too long housing. Most errors in housing length are that it was too short.
Likes For Crankycrank:
03-12-22, 10:35 AM
#4
Senior Member
Join Date: Mar 2007
Location: SF Bay Area, East bay
Posts: 7,655
Bikes: Miyata 618 GT, Marinoni, Kestral 200 2002 Trek 5200, KHS Flite, Koga Miyata, Schwinn Spitfire 5, Mondia Special, Univega Alpina, Miyata team Ti, Santa Cruz Highball
Mentioned: 52 Post(s)
Tagged: 0 Thread(s)
Quoted: 1607 Post(s)
Liked 2,584 Times
in
1,221 Posts
Are you trying to reuse the old housing? I'd just replace it with derailleur housing and ferrels. You just want it long enough to make a smooth turn, but longer is better than too short.
03-12-22, 10:41 AM
#5
I'm good to go!
Join Date: Jul 2017
Location: Mississippi
Posts: 14,984
Bikes: Tarmac Disc Comp Di2 - 2020
Mentioned: 51 Post(s)
Tagged: 0 Thread(s)
Quoted: 6191 Post(s)
Liked 4,806 Times
in
3,315 Posts
It's something that you'll probably have to make compromises on from the ideal bend. But you want don't want either end of the housing to immediately be angled as it comes out of the cable stop of barrel adjuster. Nor do you want a tight radius on the cable housing in general. But you also don't want so much radius that your cable housing is flopping all over as you hit road bumps and such. That might give you some ghost shifting.
Likes For Iride01:
03-12-22, 05:30 PM
#6
señor miembro
Join Date: Dec 2018
Location: Pac NW
Posts: 6,623
Bikes: '70s - '80s Campagnolo
Mentioned: 92 Post(s)
Tagged: 0 Thread(s)
Quoted: 3881 Post(s)
Liked 6,468 Times
in
3,200 Posts
Likes For SurferRosa:
03-12-22, 06:17 PM
#7
Senior Member
Thread Starter
Join Date: Aug 2011
Posts: 554
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 198 Post(s)
Liked 52 Times
in
41 Posts
there are several things which should be mandated, but in this instance the parts have been removed, discarded, and replacements ordered. there have been some very helpful responses.
03-13-22, 05:59 AM
#8
Senior Member
Join Date: Nov 2013
Location: Near Pottstown, PA: 30 miles NW of Philadelphia
Posts: 2,186
Bikes: 2 Trek Mtn, Cannondale R600 road, 6 vintage road bikes
Mentioned: 83 Post(s)
Tagged: 0 Thread(s)
Quoted: 472 Post(s)
Liked 1,028 Times
in
404 Posts
Pro tip 2: do not blindly assume the old stuff was correct though. Even factory original can be wrong. Be open to questioning what you encounter. Trust but verify.
03-13-22, 08:37 PM
#9
Licensed Bike Geek
PRO TIP: never actually discard any parts until the new stuff has arrived, been installed and test ridden. The old stuff does not take up much room and can be very helpful.
Pro tip 2: do not blindly assume the old stuff was correct though. Even factory original can be wrong. Be open to questioning what you encounter. Trust but verify.
Pro tip 2: do not blindly assume the old stuff was correct though. Even factory original can be wrong. Be open to questioning what you encounter. Trust but verify.
03-14-22, 10:12 AM
#10
Senior Member
PRO TIP: never actually discard any parts until the new stuff has arrived, been installed and test ridden. The old stuff does not take up much room and can be very helpful.
Pro tip 2: do not blindly assume the old stuff was correct though. Even factory original can be wrong. Be open to questioning what you encounter. Trust but verify.
Pro tip 2: do not blindly assume the old stuff was correct though. Even factory original can be wrong. Be open to questioning what you encounter. Trust but verify.
. That said, if I was having issues with shifting or braking, I would consider the possibility that it was the assembly tech’s first week on the job 
.
03-14-22, 10:24 AM
#11
Senior Member
Join Date: Feb 2022
Location: GMT-5
Posts: 928
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 532 Post(s)
Liked 414 Times
in
273 Posts
PRO TIP: never actually discard any parts until the new stuff has arrived, been installed and test ridden. The old stuff does not take up much room and can be very helpful.
Pro tip 2: do not blindly assume the old stuff was correct though. Even factory original can be wrong. Be open to questioning what you encounter. Trust but verify.
Pro tip 2: do not blindly assume the old stuff was correct though. Even factory original can be wrong. Be open to questioning what you encounter. Trust but verify.
03-14-22, 10:55 AM
#12
Senior Member
Join Date: May 2010
Location: Bastrop Texas
Posts: 4,475
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: 961 Post(s)
Liked 1,627 Times
in
1,044 Posts
Ha... Sorry to laugh... Ya never discard. Ya just throw them in a parts bin so ya can dig um up latter. Eventually that parts bin gets so well supplied you can build another bike from it... Ha... Again... But of course, you know this...
__________________
No matter where you're at... There you are... Δf:=f(1/2)-f(-1/2)
No matter where you're at... There you are... Δf:=f(1/2)-f(-1/2)
Likes For zandoval:
Likes For southpier:
Likes For soyabean:
03-14-22, 11:37 AM
#15
Senior Member
Join Date: Mar 2007
Location: SF Bay Area, East bay
Posts: 7,655
Bikes: Miyata 618 GT, Marinoni, Kestral 200 2002 Trek 5200, KHS Flite, Koga Miyata, Schwinn Spitfire 5, Mondia Special, Univega Alpina, Miyata team Ti, Santa Cruz Highball
Mentioned: 52 Post(s)
Tagged: 0 Thread(s)
Quoted: 1607 Post(s)
Liked 2,584 Times
in
1,221 Posts
