Shimano 105 rear derrailleur problem

[kjp35d]

Hi All!

I'm new to this bike repair/tunning thing and I have one question. After tuning my L tension (small sprocket) and setting the tension on my derrailleur shifter cable when I go to the biggest cog (H tension) I'm not getting the full range of motion and it stops at the third from the biggest cog. It seems as though the shifter should be able to provide a wider tension but it does not. Is this normal/acceptable with these sorts of derrailleurs? Or am I doing something wrong?

Thanks!

[nfmisso]

You should read the Shimano tech documents.

H/L are NOT tension; they are limits.

Sounds like you have everything messed up, so start over. Put the chain on the largest cog in front, disconnect the cable to the rear derailluer, which will float the rear derailluer to the high limit. Adjust the high (H) limit screw so that the chain runs smoothly in top (littlest cog) gear. Now with your hand move the rear derailleur towards the middle of the range, and shift the front to the smallest chainring (while pedalling). Now manually push and hold the rear derailleur as far as it will go towards the wheel so that it is in the lowest (largest cog) gear; adjust the low (L) limit screw so that the chain runs smoothly. Shift the front to largest chainring again, and let the rear derailleur float out to top gear. Reconnect the cable; pull it tight, but not tight enough to cause the rear derailleur to move. Now shift through the range of gears, making sure that you can get to the biggest and smallest cogs.

If you have indexed shifters, now shift into the middle gear at the back, and using the cable adjustment screw line up things so that the chain is silent.

If you messed with the B-screw also; read the tech docs on how to adjust.

read, re-read, and read a third time before messing with things.

[kjp35d]

Strange, I'm doing all of that. I also read the technical documents. I am now able to get it from the SECOND largest cog to the little one on top. But it seems as though the range of motion I get with my shifter is not large enough. I did crash the bike a while back and am thinking if maybe that has something to do with it. From what I gather this should be fairly straight forward. Should I have it inspected?

[nfmisso]

yes, get it inspected, if you are not able to determine if anything is wrong.

[Joe_W]

Also inspect the dérailleur cables and housing. If they are frayed or gunked up they won't work.

[kjp35d]

Thanks guys. Took it to the bike repair shop. The moment I told them about the shifting problem they asked me if I installed spacers. So I asked, what's that? Evidently the problem lies in the fact that the Mavic Kysirium wheels have a specific spacer arrangement for it to work. The mechanic also gave me a snide remark about the cables "[being] routed wrong" but didn't explain why. That's all the info I have for now. Will update when I get my bike back Tuesday.

[Joe_W]

Well, you have to install spacers when using a 10 speed Shimano cassette. They are narrower than a 9 speed. Cable routing is nothing magic, look at http://www.sheldonbrown.com/cables.html for hints of what to do and what to watch out for. General rule: keep the cable as short as possible and as long as necessary and avoid sharp bends.
Additionally the cables should be routed along the designated routes.

[kjp35d]

EUREKA! It turns out I had installed my shifters wrong. I had a hunch that I wasn't getting the full range of motion on them. The bike mechanic said there was a piece I had setup wrong and that's why it wasn't giving me the bigger cogs.

So, there you have it folks, I hope this really saves somebody $20.

[Joe_W]

Now, if you could tell us what you installed wrong...

[kjp35d]

NP, I have the 9 Speed Shimano Dura Ace Bar End Shift Levers. The mechanic wasn't very specific but I take it it was the large Lever Boss Cover I messed up. Installation is detailed in their tech docs.

http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/SL/EV-SL-BS77-1664_v1_m56577569830628723.pdf