Portis

OK, I'm fresh (not so fresh actually) from the garage and 3 hours of fighting with my bike. My rear derailler on my Trek 4300 has been acting sluggish when shifting. It is my winter bike and i figured it was bad housing at the derailler since i could take the housing out of the stop and spray lube in it and it would improve for awhile.

I decided to just go ahead and replace the inner wire and housing. That was no problem but now it is very hard to shift to a lower gear. (moving from smaller cogs to larger ones) It gets progressively harder the more inward the derailler moves.

I have the Park instructions printed off and have went back over everything many times. It still is acting up. I noticed that the derailler wasn't pivoting smoothly on the bolt so i removed the derailler and partially disassembled it. I pulled the spring (spring around the mounting bolt) out of the derailler and lubed it.

Currently, It seems like i might have two problems.

1. I have too much resistance in the innerwire when i try and shift to bigger cogs. It sort of sounds like it is dragging in the housing. I tried to make my housing (first time) the same as the pieces that came off, but think i might have one section that is a bit to long. See pics. Any other reasons why it would be so hard to shift to larger cogs?

2. Sometimes one click on the shifter shifts it to the next cog (inward) and sometimes it just rubs against it's neighbor and i have to hit it again. I have tightened cable via thumbscrew to the point where it starts to be sluggish in the other direction. (shifting to smaller cogs)

Bike_13

Those housing lengths are fine. Maybe they are full of grit. Pull cable out, clean with rag, lube and then refit cable. Try shifting.

Remember that the issue could also be in the shifter. Pull the dust cover off it and give it a blast with spray can penetrating lube (I like to use Weltite TF2 and then Motorex "Grease 2000").

phantomcow2

I had that problem, well my derailleur was not moving where it should on time so i thorough cleaning helped. lubricate all the pivots. I use tri flow. If you have something like pedros cog cleaner brush thing that helps greatly in removing the dirt. And finally take out your housing, really give it a good spray of WD40 and if you have an air compressor give it a long blast of air.

phantomcow2

also remember to lubricate your cables well, i like to get grease on them. I think the grease really gets into the threads of the cable. Plus the stuff i use is waterproof so its good for winter.

sydney

Yeah, and grease in the casing will stiffen up in winter and you may have no shifting. Light oil and little of it is better. Modern casing is plastic lined and doesn't need alot of extra @crap in it.

halfspeed

How did you cut your housing? Is it possible that you compressed it and it is, in fact, rubbing the cable?

phantomcow2

Yes its lined and that works nicely but lubrication is still good to have in my opinion. Grease does stiffen in the bitter cold, but i never had the problem and im in NH. Its not very warm up here

KrisPistofferson

You're not dead are you, Ranger?

phantomcow2

if your concerned about grease stiffening up you can always give tri flow a go. I used to lubricate all my housing with it, plus it comes in a spray so its easy.

pablo27

imprecise shift:
is there slack in the cable when you are on your smallest cog?

dragging:
is the cable in a straight line from where it exits the housing through the anchor?

Portis

Yes.




I think so. Look at the picture.


They are brand new. Full of grit?

Did that too.

Used Park Tool cutters. Then filed them down smooth. But yes i suppose it is possible.

Sort of. I was asleep.

Phatman

alright, try this.

put the shifter into the smallest cog on the back, and turn the pedals a afew times to get the chain there too. now, since there is slack in the cable, loosen the pinch-bolt in the derailleur, and take up the slack in the derailleur. before retightening the cable, move the barrel adjuster all the way in, then twist it out somthing like 2 rotations, this should give some adjustment room. now, retighten the pinch-bolt in the derailleur, making sure there is some tension on the cable when you do so.

now, turn the pedals forward, and while your doing that, slowly turn the barrel adjuster out until it starts to want to jump into the next highest gear. screw it back in just until it stops making noise. no further. voila. your rear derailleur is adjusted.

breakaway01

One thing that I would check--
it's hard to tell for sure in your picture but it looks like the wire does not pass correctly through the small L-shaped plate which holds the wire down on the rear derailleur. If you look at the L-shaped plate closely there is a groove through which the wire should run. I THINK the wire might not be running correctly through this groove. Check out the Shimano service manuals (PDFs available on their web site) if you're not sure.

sydney

I could also guess the retainer(L- plate) isn't positioned right either. I'd disconnect the cable,see if the derailer will move freely by hand, if so, then start checking for casing/caable issues all the way through the shifter.Check that shifter works with hand tension on cable.then double check that the cable mount and caable retainer at the rear D are correct.

Portis

Here it is. Also it looks like the thumb screw has been mashed a bit. Problem?

sydney

That 'looks' reasonable.The cable should be attached below the bolt as shown in the picture. There is a whole variety of retainers and how they are oriented. Often there is a groove in them that matches up with a groove or cable wear mark on the derailer body. The adsjuster looks ugly,and something I would ditch. You sure it's not buggered enough to be affecting the cable? If it's not affecting cable pull, I'd just screw it all the way in and make tension adjustment at the shifter if there is an adjuster. A LBS can probably give you an ajuster for nothing off a junk derailer.

Portis

I'm not sure of anything. I am pretty certain that it is a cable/housing issue, however. I am going to take all the housing off again and re-inspect. I know that when i cut the housing there were "burrs" where a piece of the spiral housing would be sticking into the opening. I tried to file the face of the housing to make it go away but that may not have worked.

Sheldon Brown's site says to file it, so i assume that just means file the face. I don't have a file small enough to stick into the hole. Thanks for the help gentlemen. I will give it another go after work.

Portis

This is my first time replacing housing so I aplogize in advance. I think i may know what the problem is although i am not at home to find out for sure. At the LBS I was given a cable/housing combo in a bag that said "universal gear cables." I assumed this would mean that it would have compressionless housing but thinking back, i don't remember seeing little wires sticking out towards me like i should have if it was compressionless.

Maybe i used the wrong housing. Surely my LBS would not have steered me wrong. Then again, i don't think i have ever left there with the right thing before so why would this be different? I ordered some new housing and cables from Jenson a couple days ago. Where is it??? Could this be the problem with my shifting???

sydney

Derailer housing is no spiral. The strands in it are parallel to the length of the housing. I duno what you used to cut it with ,but good casing cutters or a dremel tool usually work best.An ice pick works well to stick in the end of the casing to help clear things out and open the hole in the liner after the face of the casing is cleaned up. It's easy to crush or bugger the casing with the wrong cutter.. I guess you could worry the burr away with a file, but a dermel tool works alot better. It would not be hard to suspect buggered casing is this senario,considering things worked better 'before'. Also make sure the cable end is correctly installed in the shifter retainer.I'm also assuming you got the derailer back together correctly?

amahana1

you might also try using an Avid rollamajig

mtbikerinpa

The strands are parralell only if he is using the propper housing, which it is not clear yet. He stated that he used the Park cutters, which I also use, which should be good. Speaking from experience, though, any form of shears has the potential to leave a crush or burr at the edge if not done propperly.
To check if you have a cable drag, just pull the housing out of the stop and slide the housing up and down the cable. If it has resistance then you have a cable drag.

sydney

D'oh? He did say the housing was spiral.

Portis

Houston, we have a problem. I installed brake housing and cable. Holy crap!!! It said gear cable on the front and a small sticker on back said brake cable. My LBS is killing me. I told him derailler cable and he gave me brake. He even broke the package open and put the ferrules and crimps inside and restapled it so i wouldn't lose them.

On top of that I just checked with Jenson USA on my order. The cables i ordered are backordered. Where else can a person buy cable/housing/ferrules/crimps at an affordable price? I have checked loosescrews, pricepoint, performance, and nashbar and they are all quite a bit more expensive.

sydney

Go back to the LBS now that you know what you need.Accept no substitutes! If they are worth being in business they should have generic or bulk casing of the right kind that will work well. I can understand brake cable causing the incerased resistance,since it is larger in diameter,but how did you attach it to the shifter?

Portis

I just stuck it through the hole. It had a small piece on one end that fit right into the hole. IOW, it kept the cable from pulling through. Hell if i know...

Part of the trouble is that the guy working there is in a wheel chair. He can't reach the cables so i got it off the shelf myself. He did look at it and knew what i wanted however. It's just another reason i shouldn't go in there. I need to get stocked up at home.

UPDATE: Went to LBS. Turns out that i did have a shifter cable. It just was a cable housing for friction shifters. So now i think i have what i need.