Bicycle TutorBicycle Tutor

Show off your bike!

Related video tutorials:
How to Adjust Your Front Derailleur How to Adjust Your Front Derailleur
* Now with 3D interactive instructions
Weird shifting problem with RD 105 9-speed
#1
My bike is new (~300 Km) full Shimano 105 9 speed front 53-39 and back 12-25. But it has been stayed in bike shop 3 year before I buy it.
I am having a problem shifting at the end of cassette (to smallest cog) while I am on the big ring. When I'm on the road, shifting is sloppy and won't shift at all from 13 to 12 cogs. Sometimes I have the same problem in shifting from 15-13 cog. When it's in the stand or when I am on road very ease on pedal, shifting is perfect, works how it's supposed to, and I can't detect any problems. When I'm in the small ring, shifting is just fine. It's only the big ring where I am having trouble.
I have taken the bike to LBS to fix it after reading many posts here where I found to check the hanger alignment and I have insisted they check the hanger alignment. They correct the hanger aliment (and check other things) but the problem exists.
I visited techdocs.shimano.com before and download FD and RD docs. I tune FD and RD without problem (I have two another bikes and there is no problem in tuning FD and RD).
The problem is weird because is appear only under load on road but no in the stand or when I am on road very ease on pedal. I can shift from 13 to 12 cog but I need to tap two time shifter to make click and drop from 13 to 12 cog.
I have try to loosened H limiter screwes a little but without success.
Any ideas where to look next?

Reply
#2
Hmmm, that sounds very frustrating. I'd try lubing the cables as they could be a bit stiff. Let us know if that helps...

Reply
#3
I have lubed the cable but the problem remain.
I suspect that my rear mech may have a weak return spring. How can I check it and how to replace?

Reply
#4
I could be wrong, but in my experience the spring is near impossible to replace, as most derailleur bodies are assembled with rivots. If that's the case I would try a new derailleur. Then at least you'll know it was the derailleur causing the problem.

Reply
#5
Your last statement ("I can shift from 13 to 12 cog but I need to tap two time shifter to make click and drop from 13 to 12 cog.") is a little confusing, but might point to the problem. If you have to click the shifter "twice" to go from 13 to 12, then the cable tension is misadjusted and you should also have trouble getting to you largest rear cog. If you are in the 13, you souldn't be able to click twice, you should only have one click remaining on the shifter. But maybe I am misunderstanding your description and you'd think the shop would have caught that.

Reply
#6
I am going to explain again. And I am sorry for my not "good" English.
NORMAL OPERATION (WITOUT PROBLEM):

Shift from larger (13t) to smaller (12t) sprocket is done by pushing lever B (describe by Shimano tech doc) from right to left side. Near the end of the traveling there is a sound (click) and the shifting is done.

This normal operation is when my bike is on stand or when I pedaling very easy on road.

THE PROBLEMATIC SHIFTING
I made traveling the lever B from right to the end of left side BUT there is no sound (click) and hence there is no shifting. Then I release lever B and it goes to initial (right side) position. After that I again push the lever B AND at the very beginning of the traveling there is a sound (click). Shifting is now done.

This problematic operation is when I ride my bike on road. In the appendix I send four picture for commenting shift housing length.

[attachment=24]
[attachment=25]
[attachment=26]
[attachment=27]
Reply
#7
What you describe sounds like a problem in the ratchet in the shifter. But I would expect that to show up on the stand and not just on the road. You should get the 'click' of the shifter when you move the lever even if the derailleur doesn't shift the chain.
This is going to be tough to diagnose without having the bike there. Maybe it's time to try a new mechanic. If the shop where you bought the bike is telling you it's fine and won't help anymore, ask around if someone can recommend another good shop in town. Sometimes a fresh set of eyes will catch something. Be sure to tell them that the problem only shows up on the road under pedaling load.
Your cables look fine.
Sorry - good luck

Reply
#8
I have solved the problem and thank you all to participate in solving the problem. I hope this could help you if you face the similar problem.

The housing near RD was bended immediately upon leaving the barrel adjuster. This was actually bending the housing end cap. The first image show how was before.

When I put the housing below quick release axle the housing near RD is not bended immediately upon leaving the barrel adjuster. See the second image.
Yes this is temporary solution and I need a longer housing in this case allows the housing to enter straight.

[attachment=28]
[attachment=29]
Reply
#9
Thanks for the photos... I wouldn't worry too much about the bend at the housing cap. The cable has better flow that way, as opposed to being tucked under the quick release which looks like it's causing to sharp of a curve.

Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  Front derailleur shifting problem dventura 1 5,987 02-28-2017, 06:07 PM
Last Post: nfmisso
  Shifting Problem fulltimerart 2 3,905 08-11-2016, 10:17 PM
Last Post: fulltimerart
  7 speed bike / 5 speed shifter handle 6716 1 4,539 05-23-2016, 08:36 PM
Last Post: DaveM
  Single-speed to 8x geared conversion shifter problem Tomtebi 4 6,284 01-17-2016, 11:43 AM
Last Post: Tomtebi
  Front Derailleur problem/whole shifting system benonidoni1 9 5,527 09-08-2014, 02:19 AM
Last Post: cny-man
  8-speed shifter and derailleur with 7-speed sprocket? smmr89 8 8,872 11-03-2013, 08:18 AM
Last Post: 1FJEF
  How to install a shifting cable to a shimano nexus 7 speed? pippobaudo 5 27,503 01-11-2012, 05:43 PM
Last Post: FastFahl
  21 INCH 12 speed rear problem jacobojajati 3 6,594 07-06-2011, 07:54 AM
Last Post: Joe_W
  Shifting problem Sparetime 3 5,486 04-13-2011, 02:03 AM
Last Post: RBurrelli
  Weird (and annoying) problem! Rabsh 9 7,385 11-05-2010, 12:40 PM
Last Post: Rabsh

Forum Jump:



ISSN 1918-3445 © Copyright 2007-2010 Bicycle Tutor / Privacy Policy / Created by Alex Ramon

feed