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Discussion Starter · #1 ·
Got my ID built up this weekend and i absoultely love it. However, noticed from the start that the rear mech was slipping. I felt there was not enough air in the shock anyway so added some which has 80% solved the problem but not quite. Anyone had a similar problem and what did you/can i do ? Please make any suggestions idiot proof, i'm a non techy female ;)

Cheers folks

Diz :)
 

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No, that's not phonetic
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Ghost shifting on full suspension bikes is generally due to cable housing flex. The loop of cable housing which runs between the back of the top tube and the top of the seat stays flexes as the suspension compresses. The effective length of the housing "grows" relative to the cable inside of it, so it tends to pull the rear der towards a larger cog. The best way to solve this is think about how to minimize the amount of housing which will flex. Make sure the rear der cable housing makes a short, direct run across the top tube/seat stay gap.

Also, Sram drivetrains are much less prone to ghost shifting from housing flex because they use a 1:1 actuation ratio whereas Sh!mano uses a 2:1. This means that the Sram is half as affected by housing flex as the Sh!imano is.
 

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Amphibious Technologies
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I echo all of tscheezy's comments. I have an ID and had bad ghost shifting problems with a Shimano XTR rear derailler. I am now runnig SRAM XO. The other cause of the problem was a very slightly bent derailleur hanger, so check yours. And don't over tighten the rear wheel skewer, it makes the portion of the hub that contacts the seatstay dig into the seatstay (material is kinda soft) which results in a slight misalignment of the hanger. Also make sure the hanger bolt is tight.
 

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Just another FOCer
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I had a ghost shifting problem on a 01 Truth and then on my ID. (Components moved from the Truth to the ID.) The problem for me happened on steep climbs only. The culprit turned out to be the XTR rear derailleur. I tested an LX derailleur with no problems. I ended up getting a SRAM X9 rear derailleur and X9 trigger shifters. No problems since.

Best of luck,

Winston

SCUBAPRO said:
I have an ID and had bad ghost shifting problems with a Shimano XTR rear derailler. I am not runnig SRAM XO.
 

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Discussion Starter · #5 ·
It is indeed an xtr rear mech. So, looks like i might have to swap it then. Don't think there is a problem with it being bent or anything, i had the bike built up by a guy who's spot on. Don't want to change to sram really, wonder if i went xt ? What's the reliability/shifting like on lx ?
 

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never encountered this with my xt with an xt shifter...when we built the bike, i was told to ensure that there be sufficient cable housing at the RD so that the cable does not pull when under stress...seems to work very well

however, i will be switching my xt FD to a sram x gen shortly to eliminate the cable noise in the lower gears shortly.
 

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No, that's not phonetic
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Dizzy, you would have to get Sram shifters AND rear der. Shimano's 2:1 does not work with Sram's 1:1 components (front ders are compatible). You can probably make your XTR work. Just minimize the housing run I mentioned and try to figure out which way the der is jumping when the housing compresses. Err on adjusting the der a bit in the other direction so that compression does not result in enough cable pull to move the der to the next cog. Also make sure the housing is not catching anywhere (like on the seatpost binder collar).
 

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dizzyone said:
Got my ID built up this weekend and i absoultely love it. However, noticed from the start that the rear mech was slipping. I felt there was not enough air in the shock anyway so added some which has 80% solved the problem but not quite. Anyone had a similar problem and what did you/can i do ? Please make any suggestions idiot proof, i'm a non techy female ;)

Cheers folks

Diz :)
I agree with Tscheezy. Also, the derailler cables on a new bike will seat into the end caps and will cause the derailler to go out of adjustment. You may only need to adjust the tension on the cable. THis is easily done by turning the adjustment knurled know on the shifter counter-clockwise....a quarter turn at a time. I've had good success getting rid of that problem just with adjustments.

If adjusting (usually tightening the cable) doesn't work, follow TS's recommendations.
 

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Discussion Starter · #10 ·
hi guys, just spoke to my mechanic who has asked me to ask those of you who had ghost problems with xtr rear mechs, if those were the reverse pull type or the older type ? Mine's reverse pull and he thinks there have been some problems with them. Anyhow im taking the back in for him to have a fiddle with

Thanks

Diz :)
 

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Just another FOCer
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Mine was a regular 2001 XTR. Not the rapid rise type.

dizzyone said:
hi guys, just spoke to my mechanic who has asked me to ask those of you who had ghost problems with xtr rear mechs, if those were the reverse pull type or the older type ? Mine's reverse pull and he thinks there have been some problems with them. Anyhow im taking the back in for him to have a fiddle with

Thanks

Diz :)
 

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tscheezy said:
I have never run rapidrise and never will.
Wow, TS. For a guy that seems to run every imaginable setup, that's a pretty bold statement. ;)

Personally, I also don't like rapid rise.....but that mostly because I don't want to have to change the deraillers on both of my bikes and I don't want to have to get used to shifting the other way. What's your beef with RR?
 

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The Ancient One
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I changed to rapid rise when it first came out because it made more sense. I thought that was how derailers should always have worked. I've used it ever since with no problems other than what you have with any derailer.

I didn't have to get used to shifting backwards because I changed to grip shifts at the same time (thumb pain problems) and had to get used to a new motion anyway.
 
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