cable problems

lurch · 08-26-09, 09:11 PM

I've got a 2005 Jamis Dakar XLT that has never shifted right...I built the bike from scratch and at this point I've had 3 different cable setups for the shifters. Right now I'm running "sram flak jacket" cables for the both the front and rear and I'm having problems with e cable sliding through the housing when shifting. On the front derialur I end up having to kick it in order to shift in to the lowest gear and the rear sometimes I will have to down shift 2 and up shift one just change one gear.

Any ideas on what the problem could be? I try to keep everything lubed...is there a lube I could put on the cables and in the housing? Or should I get a different cable setup?

2mbb · 08-26-09, 10:15 PM

A picture might help. If you've used three different types of cable/housing and they were matched (e.g. same vendor, part of a kit), then you might have something wrong with your installation technique--bends too tight, etc.

what deraillure and shifter components do you have?
Can you see where the cable is hanging up? Usually the cable doesn't go through housing all the way from shifter to deraillure, and if the cable is hanging up in one section it should be slack before that section of housing when you shift.

I sometimes put a little grease on the cable before I install it in the housing. Other than that, lube should not really be needed.

FirstToy · 08-26-09, 10:56 PM

are you cutting the housing ends without barbing into the cable?

like mmb said, look at routing

check your derailleurs that they have smooth action and not getting caught up.

make sure your rear derailleur stop screws are adjusted correctly so the derailleur is not hitting the frame or dropout or not allowed to travel far enough

try teflon coated cable for smoother action but you have new cable so that is not your issue.

cruiser7773 · 08-26-09, 11:04 PM

Could be routing, or it could just be derailleur adjustment. If your housing sections are too long or too short then the derailleur will not travel the same distance as the shifter. Are you running SRAM 1:1 shifters or Shimano 2:1 system? For the price of three cable sets you could of had your local shop make it run and gotten a free tune after the cables streched.

MANUCHAO · 08-27-09, 10:38 AM

what type of cables have your ran?
Where these kits or different cables and cable housings..

As MBB stated.. check for bends on the housings.. did yah used a good set of cable cutters?
I suggest using XTR shifter cable kits.. they are coated and can take on a lot of abuse..
I also think there is some Teflon and Gore coated cables out there that are pretty sweet..
Putting some lube (wax based or grease) in the housing does not hurt things... I always do it.

If you have had this issue from the beginning.. your problem might be the shifters or derailleurs

Let us know whats up .....

lurch · 08-27-09, 08:59 PM

Quote:

Originally Posted by 2mbb

If you've used three different types of cable/housing and they were matched

what deraillure and shifter components do you have?
Can you see where the cable is hanging up?

Each time I have changed the cables I have matched all of the housing...1st time i used cheap housing and cable I bought at the local bike store...2nd I used better housing and cable from the bike store...and what I'm running now is the Sram kit called "flak jacket"

For the rear derailure I'm using a Shimano Deore XT, the front is a Sram X Gen and the shifters are Sram Rockets. I set the derailleurs up according to the instructions and have check the clearence and L & H settings multiple times. So I'm sure they are right.

There is one spot on the cable just in front of the shifter where the outside plastic sleeve is bunched up but does not appear to interfere with the braided metal sleeve in the housing.

Quote:

Originally Posted by FirstToy

are you cutting the housing ends without barbing into the cable?

I used large wire cutters to cut the housing...which tends to flatten the housing. But after cutting them I would use an awl to open the housing and work them back into shape. Maybe some issues there?

Quote:

Originally Posted by MANUCHAO

Putting some lube (wax based or grease) in the housing does not hurt things... I always do it.

If you have had this issue from the beginning.. your problem might be the shifters or derailleurs

Let us know whats up .....

I thought about putting white gease in the housing but wondered if it would gum up after time. What about graphite? It worked in the pine wood durby

I got the shifter and the front derailleur new and the rear derailleur used. If I tweak the rear derailleur before a ride it will work for about 1 or 2 rides, then start messing up. The front has never really worked smooth.

lurch · 08-27-09, 09:12 PM

2mbb · 08-27-09, 09:25 PM

The front cable housing looks a little tweaked where it butts up to the shifter. Is it bent or is it just the angle of the picture?

If you're riding in the gearing shown, you really shouldn't be. You put a lot of side stress on the chain and you are essentially stretching the rear derailleur

Otherwise your cable routing looks OK. So I would start to look at shifters or derailleurs.

MANUCHAO · 08-28-09, 09:42 AM

Looking at that last pic there.. I would say the chain is waaaaaay to short...
Other things that you might want to cosider is getting a new rear derailleur and also look at the rear derailleur hanger, it may be bent.. try to reposition your front derailleur it would rub some when you have it ont he stand but once under load it should not make any noise....

I have used the Park Tool Website for reference...
Check it out..
Park Tool Website

MANUCHAO · 08-28-09, 09:43 AM

Also.. I cant tell if you have a short cage or long cage.. derailleur..but you might want to use the long cage if you are not running it already..

MANUCHAO · 08-28-09, 09:50 AM

One last thing.. how old is your chain/cassette? If you replace them both at the same time then you should be golden. Rule of thumb is replace both at the same time.. or you will have shifting problems...

lurch · 08-31-09, 07:56 PM

My chain/cassette as well as crank are new and I have a long cage.

But i did make some progress and fixed the front derailleur problem.... the cable housing separated. AND when I saw the problem it jingled a few bells...this is why I replaced the cable house the other two times. (It's been a couple of years since I MTBed)

SOOOOOOOOO..I got out the angle grinder and cut off steel "rods" of the housing, put it all back together with a new cable, and now it shifts correctly.

I imagine the rear derailleur system has similar problems....

Is there anyway around this problem? It seems that all housing tend to separate (at least ones that I've used)?

Even with the housing end caps in place they still come apart!!!

cruiser7773 · 08-31-09, 08:16 PM

Glad to hear that you got the front end working correctly. As was said, I hope the gearing in the photo is a product of your adjustment attempts and not how you normally ride. I also see that you have a Shimano deraillure and SRAM shifters. Are you sure the shifters are compatible with Shimano? SRAM deraillures run on a 1:1 ratio and Shimano runs 2:1. SRAM does make a 2:1 shifter, but if that's not what you have, you will never shift correctly with that XT.

2mbb · 08-31-09, 08:46 PM

So you replaced the cable but not the housing? I'm not sure what the picture above shows. Is that just housing with the stiffening wires but no cable? If that's the case, then that's a problem. You should be using a good set of cable housing cutters to cut the housing. Then you also need to use the ferrules. If the plastic ferrules don't hold up, then you should use metal ferrules. I experience the stiffening wires creeping out the ends of the housing, but never more than 1/4" or so.

lurch · 08-31-09, 09:20 PM

Quote:

Originally Posted by cruiser7773

Glad to hear that you got the front end working correctly. As was said, I hope the gearing in the photo is a product of your adjustment attempts and not how you normally ride. I also see that you have a Shimano deraillure and SRAM shifters. Are you sure the shifters are compatible with Shimano? SRAM deraillures run on a 1:1 ratio and Shimano runs 2:1. SRAM does make a 2:1 shifter, but if that's not what you have, you will never shift correctly with that XT.

That's a good question...I think they are compatibly because I can adjust the setup to work on the stand but after a few rides it acts up. I'm still thinking it's in the cables (based on the findings of the front cables) and partially in the XT derailleur. I did get it used and it has some good battle scares...probably a good idea to replace it with a Sram.

The gears selected are not the gears I run on the trail...just testing purposes. I set the chain up as long as possible, any longer and the chain sags in the lowest gears.

Quote:

Originally Posted by 2mbb

So you replaced the cable but not the housing? I'm not sure what the picture above shows. Is that just housing with the stiffening wires but no cable? If that's the case, then that's a problem. You should be using a good set of cable housing cutters to cut the housing. Then you also need to use the ferrules. If the plastic ferrules don't hold up, then you should use metal ferrules. I experience the stiffening wires creeping out the ends of the housing, but never more than 1/4" or so.

Yeah those are just the stiffen wires sticking out of the housings...and I'm using metal ferrules.

Not sure why it's happening so bad...but I did cut the stiffen wires down to flush. Maybe they won't move any more?

cruiser7773 · 08-31-09, 09:24 PM

The ratio is only a rear deraillure thing.

tcb · 09-01-09, 10:27 AM

make it a single speed and leave those problems behind...

2mbb · 09-01-09, 08:20 PM

Quote:

Originally Posted by lurch

Yeah those are just the stiffen wires sticking out of the housings...and I'm using metal ferrules.

Not sure why it's happening so bad...but I did cut the stiffen wires down to flush. Maybe they won't move any more?

The problem is that some of the wires are now too short. Those wires are supposed to run the entire length of the housing. The wires are what keeps the housing from compressing. If the housing does compress, then the cable won't pull a far and your shifting won't be accurate. I'm back to recommending you get a quality cable housing cutter, and replace the housings with new.