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-   -   Shimano XTR Revisit (http://www.bikeforums.net/tandem-cycling/517241-shimano-xtr-revisit.html)

ftsoft 03-05-09 09:16 AM

Shimano XTR Revisit
 
I know this has been discussed. I am referring to the rather vague shifting with the CoMotion Speedster et al and the 10 spd XTR rear derailleur. It's really not that bad, but I would like to tweak it a little to see if I can make it just a tiny bit more acceptable.

At the hand made bicycle show in Indy last week I talked to some of the tandem builders about this and came away with some suggestions.

1. Use the Jagwire tandem shift cable. Supposedly smoother and less likely to hang up.

2. Use the Nokon compressionless cable housing (looks like a series of beads). Pretty expensive.

One of the tandem had an arrangement where the nokon housing was used just on the section leading from the levers.

I plan to go through the shifting system and relube and tighten everything, but, how much of the problem is the XTR itself I wonder. Any thoughts?

Frank

joe@vwvortex 03-05-09 10:20 AM

Check the cable guide on the bottom bracket. I recently replaced the shift cables with Jagwires - which i've used from the start and put new housing for both the front and rear derailleurs at all points. The front was butter smooth but the rear was still a bit stiff. The guide is oddly shaped and gives some friction. It's too narrow to fit a piece of inner housing and that makes it worse. I cleaned it thoroughly and lubed it a bit with some dry lube and shifting improved a considerably. I also tightened the spring tension on the XTR derailleur itself (I have the older version).

tandem rider 03-05-09 10:45 AM

Check your derailleur hanger alignment, it can cause shifting problems. What type of cog set do you have? Some shift better than others.
Sheldon

PMK 03-05-09 10:48 AM

Good comment on the XTR spring tension.

When we had our Speedster, I was able to use some old Gore Tex cable liner and slide it through the guides. Seemed to help ours.

While not as big of an aid, I also get a better alignment of the cables by coming along the downtube with rear cable on left and front cable on right. After the cables pass through the BB guide I cross them. Just minimizes any reverse bends in the longest cable housing run.

Another thing you might try is an Avid Rollamajig. Some folks love them others don't. Fairly inexpensive.

Pretty much a common sense item, but sometimes overlooked, after cutting your housing to length, try and get them ground or sanded square and flat if you don't use cable cutters. After they are true, take a scribe and open the inner liner by inserting the scribe point to reshape the liner round.

I'm sure most of this is obvious. Best of luck with it.

PK

joe@vwvortex 03-05-09 01:48 PM

Quote:

Originally Posted by PMK (Post 8473103)
Good comment on the XTR spring tension.

When we had our Speedster, I was able to use some old Gore Tex cable liner and slide it through the guides. Seemed to help ours.

While not as big of an aid, I also get a better alignment of the cables by coming along the downtube with rear cable on left and front cable on right. After the cables pass through the BB guide I cross them. Just minimizes any reverse bends in the longest cable housing run.

Another thing you might try is an Avid Rollamajig. Some folks love them others don't. Fairly inexpensive.

Pretty much a common sense item, but sometimes overlooked, after cutting your housing to length, try and get them ground or sanded square and flat if you don't use cable cutters. After they are true, take a scribe and open the inner liner by inserting the scribe point to reshape the liner round.

I'm sure most of this is obvious. Best of luck with it.

PK

I'll bet the gore cable liner is probably a bit more flexible then the typical plastic liner which is why it worked. I tried several different "liners" and all created more friction. IMO - the cable guide for the rear derailleur is really poorly designed.

ftsoft 03-05-09 04:10 PM

Thanks for all of the great replies. Now that it's warming up and I can work in the garage I'll start implementing the suggestions.

Frank

JayB 03-08-09 09:23 AM

Tightening rear derailleur
 
Joe,
Could you tell me how to tighten the rear derailleur and by how much? I also have XTR with ten speed IRC 11-34. Works reasonably well but could be a bit better.
Thanks, JayB

PMK 03-08-09 09:44 AM

Quote:

Originally Posted by JayB (Post 8489976)
Joe,
Could you tell me how to tighten the rear derailleur and by how much? I also have XTR with ten speed IRC 11-34. Works reasonably well but could be a bit better.
Thanks, JayB


Not Joe, but if it helps check for this.

I have in hand a 9 speed XTR long cage, RD952. If you look at the cable clamp bolt from the end, then shift your focus about 13mm aft of the cable clamp and between the links (if the bike is upright you may need lay on the floor and look up, or better yet, lay the bike on its left side). This der has a silved philips head to turn, this moves a small cam the adds or decreases spring tension.

Hope it helped, I don't believe the new "X" type have this feature, but its easy to check.

PK

Weaklink 03-08-09 08:19 PM

IRD Cassette?
 
If you have an IRD cassette, throw it in the trash ASAP. I had vague shifting on my Cannondale. Replaced the casstte to an Ultegra, granny gear to a 24, and a chain checker up front. Flawless shifting now and a wider range of gears. I have a thread somewhere on here, maybe you can search for it.

James

JayB 03-09-09 04:58 AM

Tightening derailleur
 
Oh, yes, I see. Never noticed that screw before. (I have the same sort of derailleur.) The way it operates, with a slotted feature, it will only give you two settings of tightness, though, right?
Thanks, JayB

EnterpriseZ 03-15-09 04:03 PM

We have a Santana with the 10 speed XTR rear and it was not as responsive as our old 9 speed XTR Santana. After going through all the obvious cables, alignments, chain, etc., it was better but still not as responsive as we wanted.

The way we made it acceptable was to reduce the lateral float of the upper derailleur pulley. With less float (we are at ~half the original), you have to adjust things carefully to minimize chain noise. However, we are much happier with the system now.

dvs cycles 03-16-09 08:14 AM

Quote:

Originally Posted by EnterpriseZ (Post 8534523)
We have a Santana with the 10 speed XTR rear and it was not as responsive as our old 9 speed XTR Santana. After going through all the obvious cables, alignments, chain, etc., it was better but still not as responsive as we wanted.

The way we made it acceptable was to reduce the lateral float of the upper derailleur pulley. With less float (we are at ~half the original), you have to adjust things carefully to minimize chain noise. However, we are much happier with the system now.

How did you reduce float?

EnterpriseZ 03-16-09 04:04 PM

I did ours in two stages. To verify the results, I first carefully made a couple shims with the right size hole to limit the float. I don't remember the exact numbers but I think it was a little over 0.030" float when we started and we cut ~ in half. After we verified that it worked, we purchased an aftermarket pulley and permanetly modified the bushings to give the right amount of float. We have been using the reduced float pulley system for several hundred miles and don't ever plan on going back...

JayB 02-27-10 10:09 AM

Modifying jockey wheels
 
Quote:

Originally Posted by EnterpriseZ (Post 8541188)
I did ours in two stages. To verify the results, I first carefully made a couple shims with the right size hole to limit the float. I don't remember the exact numbers but I think it was a little over 0.030" float when we started and we cut ~ in half. After we verified that it worked, we purchased an aftermarket pulley and permanetly modified the bushings to give the right amount of float. We have been using the reduced float pulley system for several hundred miles and don't ever plan on going back...

EnterpriseZ,

Are you still happy with this solution? I mean, is the modified jockey wheel still giving you improved shifting?

EnterpriseZ 03-01-10 06:21 AM

JayB,

We are still using it and still happy with it. At some point we may go for one of the expensive ceramic bearing pulleys but I'm not sure we would notice the difference over what we have today. Note from the earlier post that we first went through all the other obvious items with cables, etc. before we did the pulley. One without the other likely would not be as effective.

Enterprise Z
Michigan

JayB 03-02-10 05:00 AM

EnterpriseZ,
Thanks for the update.


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