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My first quality mountainbike was a '97 GT Karakoram with a full LX 8sp drivetrain. After replacing the wet noodles Shimano was trying to pass off as cranks that year, I never had a bit of trouble with the drivetrain. Always shifted, never slipped over the chainrings or cogs, chains rarely broke...

Then I got the idea I needed a new bike with a new XT 9sp drivetrain. I remember the first few hundred feet down the trail thinking man this drivetrain rocks. After that I remember thinking - "damn those cables must be stretching" and "who makes a stronger chain than Shimano?". After readjustment in the garage for preparation of the next ride, I got the same results. Great for the first little ways down the trail, but **** after I put some real torque on the drivetrain.

After 3+ years of never really being able to use the very inner and/or very outer cog, misshifting, chain sliding over the rear cassette, chains breaking, I decided to get rid of the 9sp XT stuff on ebay while shimano prices were high. For replacement, I won a $7 set of 8sp Centera Gripshifters complete with cables, housing and grips on ebay. I mated them to alivio derailers I had in my attic and an 11/30 8sp SunRace cassette I won for $6 from the same seller. I now remember how shifting is supposed to work. I can use all the gears. Each click goes from one right to the other. The chain never slides over the teeth of the cogs. Havn't broken a chain. Havn't had to readjust any cables... Life is great.

Does anyone know how to setup a reliable/durable 9sp drivetrain? Is SRAM's 9sp stuff any better than Shimano's? Is there a 9sp chain that lasts more than a hundred miles and doesn't break under high torque? Am I overreacting to the 9sp vs. 8sp? My other theory is that the 11/34T rear cassette was a bit much for the XT derailer. Maybe a 9sp setup with 11/32 in the back and a good 9sp chain would work?
 

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npstaehling said:
I can use all the gears. Each click goes from one right to the other. The chain never slides over the teeth of the cogs. Havn't broken a chain. Havn't had to readjust any cables... Life is great.
My experience exactly with 9sp for the last 4 years, never a problem, Northwest Washington riding. Both SRAM Gripshift and Shimano Rapid Fire.

Monte
 

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Well I had SRAM on my last bike and I could get it to shift flawlessly. I recently purchased a new bike this year with XT. It worked OK. I could shift through all the gears. Occasionally, one of the gears would not go fully into gear and I would press the lever and to get it to shift into gear. If I pedaled backwards, I would find that the chain would catch a little on the cassette if it was not lubed enough. I figured that I could not get it to run quite perfectly because my old bike was a hard tail and my new one a FS.

Finally, I figured I would give the X.9 triggers a chance on my new bike. I always like to try new components. I had the X.0 twist shifts on my old bike. I took the X.0 derailleur off of my old bike and put it on my new one. I found that with this setup, I could get my new bike to shift flawlessly just like my old one. Since I have a mechanical engineering background, I decided to try and figure out the reasoning behind the better shifting. Here are some possible reasons:

1) No adjustment barrel on the back of the derailleur (therefore the barrel is not going to twist unexpectedly). Who knows if this is actually the case.
2) Higher tension spring in the derailleur.
3) The middle gear pulley on the SRAM sits a little more forward than the XTs, therefore allowing more chain to sit on the cassette.

Know keep in mind, there is a large amount of people that have no problem adjusting their XT components. I just found that I had an easier time with the SRAM
 

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I used to have a '97 karakoram as well, kick ass bike. It was stolen in '01 with 2240 miles on it. The cassette and chain had stretched almost to the point where it couldn't be ridden at that milage. A snake oil salesman at the LBS talked me into an i-drive 5.0. with full deore drivetrane. In the first month the chain and FD broke, while commuting on pavement. Within the first year, the cranks, cassette and second chain went. second year, LX replacement cranks, clipless pedals, another cassette, another chain. My experience is the cassettes and chains last 1000 miles even w/o regular chain replace, 1000 miles was the recommended chain replace point on the 8 speeds. My solution was that I found a '97 karakoram frame brand new on ebay and have outfitted it with 8 speed parts. Glad I did too, the i-drive pivot or something is going. It's eaten two sets of eccentric bearings in the last couple of months. Except shifters you can still get good 8 speed stuff, I really dislike the 9 speeds
 

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do your mechanical engineering textbooks....

skibud2 said:
Well I had SRAM on my last bike and I could get it to shift flawlessly. I recently purchased a new bike this year with XT. It worked OK. I could shift through all the gears. Occasionally, one of the gears would not go fully into gear and I would press the lever and to get it to shift into gear. If I pedaled backwards, I would find that the chain would catch a little on the cassette if it was not lubed enough. I figured that I could not get it to run quite perfectly because my old bike was a hard tail and my new one a FS.

Finally, I figured I would give the X.9 triggers a chance on my new bike. I always like to try new components. I had the X.0 twist shifts on my old bike. I took the X.0 derailleur off of my old bike and put it on my new one. I found that with this setup, I could get my new bike to shift flawlessly just like my old one. Since I have a mechanical engineering background, I decided to try and figure out the reasoning behind the better shifting. Here are some possible reasons:

1) No adjustment barrel on the back of the derailleur (therefore the barrel is not going to twist unexpectedly). Who knows if this is actually the case.
2) Higher tension spring in the derailleur.
3) The middle gear pulley on the SRAM sits a little more forward than the XTs, therefore allowing more chain to sit on the cassette.

Know keep in mind, there is a large amount of people that have no problem adjusting their XT components. I just found that I had an easier time with the SRAM
...say anthing about NOT lubing cassette cogs, lest sand and grit stick to them and grind them into crap? Or maybe you skipped class to go riding the day they discussed that.
 

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Save your words

bulC,

Maybe you skipped english class to go ride. In the sentence, "I would find that the chain would catch a little on the cassette if it was not lubed enough", 'chain' is the primary noun, therefore 'it' refers to the chain. I was never talking about the cassette being lubed. Do me a favor, don't write a response if you don't know how to read the thread in the first place.

Now, I figure since, you are most likely one of those people that are going to respond to this reply by attempting to tear apart my grammar. I noticed I typed 'know' instead of 'now' when I typed it fast -- just to save you your pathetic time.

Mike
 

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skibud2 said:
Since I have a mechanical engineering background, I decided to try and figure out the reasoning behind the better shifting. Here are some possible reasons:

1) No adjustment barrel on the back of the derailleur (therefore the barrel is not going to twist unexpectedly). Who knows if this is actually the case.
2) Higher tension spring in the derailleur.
3) The middle gear pulley on the SRAM sits a little more forward than the XTs, therefore allowing more chain to sit on the cassette.

Know keep in mind, there is a large amount of people that have no problem adjusting their XT components. I just found that I had an easier time with the SRAM
I think your point 2 may be valid but not really sure about 1 and 3.

I recall that before SRAM did their own rear mechs, you used to be able to buy stronger springs for Shimano derailleurs when used with the old Gripshift.

Anyway, as i understand it, (and sorry if this isn't new to you), the primary reason that SRAM seems to experience less shifting problems is because of the 1:1 cable-pull to derailleur movement ratio. That is, for every 1mm of derailleur (chain) movement, you need to move the cable 1mm. This makes it half as susceptible to cable stretch and misalignment than Shimano's 1:2 system which moves the derailluer 2mm for every 1mm of cable movement. Or to put it another way, lets say for arguments sake you need greater than 0.5 mm of derailleur misalignment before you will experience shifting skip. On Shimanos system this translates so that anything greater than 0.25mm of cable misalignment would cause shifting skip. SRAM on the other hand can be out of alignment by up to 0.5mm before any shifting skip would occur.

Having said that I think (no back up) that SRAMs twist shifter mechanism may not be quite as precise as the rapid-fire shifter mechanism. Possibly this was a big reason SRAM adopted the 1:1 ratio in the first place. I know that the worst shifting drive train I ever had was a 1:2 SRAM shifter, and that was on 8-speed.
 

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milroy,

Thank you for bringing up that point. The reason I do not think the shifting difference is due to the ratio differences is because when I adjusted the alignment of the derailleur, I noticed that with the XT derailleur, the chain was more likely to catch on the cassette in a smaller range of adjustment.
 

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Not quite...

milroy said:
I think your point 2 may be valid but not really sure about 1 and 3.

I recall that before SRAM did their own rear mechs, you used to be able to buy stronger springs for Shimano derailleurs when used with the old Gripshift.

Anyway, as i understand it, (and sorry if this isn't new to you), the primary reason that SRAM seems to experience less shifting problems is because of the 1:2 cable-pull to derailleur movement ratio. That is, for every 1mm of derailleur (chain) movement, you need to move the cable 2mm. This makes it half as susceptible to cable stretch and misalignment than Shimano's 1:1 system. Or to put it another way, let's say for arguments sake you need greater than 0.5 mm of derailleur misalignment before you will experience shifting skip. On Shimano's system this translates directly so that anything greater than 0.5mm of cable misalignment would cause shifting skip. SRAM on the other hand can be out of alignment by up to 1mm before any shifting skip would occur.

Having said that I think (no back up) that SRAM's twist shifter mechanism may not be quite as precise as the rapid-fire shifter mechanism. Possibly this was a big reason SRAM adopted the 1:2 ratio in the first place. I know that the worst shifting drive train I ever had was a 1:1 SRAM shifter, and that was on 8-speed.
Unfortunately, you're a little mistaken. Sram's new system is 1:1 whereas Shimano, uses 2:1. Therefore, theoretically, the new Sram system is much more susceptible to improper adjustment than their Shimano counterparts. Notice how I said 'theoretically' though as I've found the exact opposite to be true.

Dunno...
 

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Thanks for that Manitou

manitou said:
Unfortunately, you're a little mistaken. Sram's new system is 1:1 whereas Shimano, uses 2:1. Therefore, theoretically, the new Sram system is much more susceptible to improper adjustment than their Shimano counterparts. Notice how I said 'theoretically' though as I've found the exact opposite to be true.

Dunno...
Well we're both wrong. And both right.

From the SRAM website faq...

Q: What's the deal with different actuation ratios?
A: Well, SRAM's ESP design uses a 1:1 ratio. This means that for each millimeter of cable moved in the shifter, an equal millimeter will be moved in the derailleur. This allows a greater acceptance of off-road conditions (dirt, water, sand, etc.) and also gives SRAM a unique shifting technology. Conversely, Shimano uses a 1:2 ratio for it's shifting systems. This means that for every one millimeter of movement in the cable there will be two millimeters of corresponding movement in the rear derailleur. The ratios are not the same; therefore, you cannot use an ESP shifter and a Shimano derailleur, or vice versa.


My reasoning above is consistent in respct of why SRAM's is less prone to misalignment, but the ratios are wrong, I'll edit the post to correct...
 

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Hrmph!

milroy said:
Well we're both wrong. And both right.

From the SRAM website faq...

Q: What's the deal with different actuation ratios?
A: Well, SRAM's ESP design uses a 1:1 ratio. This means that for each millimeter of cable moved in the shifter, an equal millimeter will be moved in the derailleur. This allows a greater acceptance of off-road conditions (dirt, water, sand, etc.) and also gives SRAM a unique shifting technology. Conversely, Shimano uses a 1:2 ratio for it's shifting systems. This means that for every one millimeter of movement in the cable there will be two millimeters of corresponding movement in the rear derailleur. The ratios are not the same; therefore, you cannot use an ESP shifter and a Shimano derailleur, or vice versa.


My reasoning above is consistent in respct of why SRAM's is less prone to misalignment, but the ratios are wrong, I'll edit the post to correct...
I really hate being wrong! :p

*EDIT: I might not be afterall! :) According to a google search and sram's own web page http://www.sram.com/mtb/shifters/index.asp its 2:1
 

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Been running 9 spd Shimano on my bike and my wifes for 4 years each. No problems. I've switched out cassettes and chains(again shimano) and rings and adjusted them by the book. No problem. Still if you can't adjust it I suggest the Sram stuff. Only heard good things so far and maybe you'll be able to get those adjusted right.
 

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Cassette offset?

I wonder if the offset of the cassette on the axle has any effect on whether you can get the XT derailleurs to go into all the gears correctly? I would have given that a try, but I needed to insert washers for each bit of offset on the axle. I believe that with the shimano hubs, you can adjust the offset pretty easily.
 

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My gears are (were) spot on.

I'm on Sh!mano X T '03 cranks, cogs, deraileurs, with a [email protected] PC89r chain. Once I got it dialed in, it ran perfectly. Instant low effort shifts even under load, I can dump several cogs with a single RF thumb cranking, etc.

The Sh!mano stuff is solid, but 9 speed setup has to be spot on. It's pretty sensitive to being out of adjustment.

Check your setup, including your chainline. Your cogs should be dead-on-balls centered (or within a mm or two of DOBC) with your middle ring.

If your chainline is too far out of whack, you get exactly what you are talking about.
 

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Been running 9-speed LX/XT with SRAM chains and cassettes since '91....have no more problems (nor less...) than the old old school 7-speed LX I have on my ancient HT....As long as the drivetrain is properly cleaned and lubed regulary, and properly adjusted, there should be no problem (....well, as little problem as can be expected given the characteristics of the modern
externally multi-geared bike drivetrain - I suppose if keeping it working is a problem, you could consider the Speedhub internal gear hub....pretty cool, but kinda heavy, I presume...)
 

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Only when swapping cables....

otherwise I hadn't needed to adjust a 9sp drivetrain..... well, only once... a bud stuck my bike into a trunk and made a mess with my chain and strtched the clabe... half turn at the barrel and matter solved.

I suffer from some kind of ghost shiting on the second (28t) of a SRAM 7.0 cogset but I've heard that is kinda common and hadn't heard about a fix. Seriously not a problem with it being 9sp.

The full deore drivetrain on another bike I have is working flawlessly (although it ate a chain after 800 miles).
 

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Fuelish said:
Been running 9-speed LX/XT with SRAM chains and cassettes since '91....
OOOOOPS !!!!! ...make that, "since ''01" ....heh....can you not edit replies ???? (or does ability to edit only last for a certain length of time ???) I couldn't find an "edit" button...oh, well, no biggie...
 

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Warp2003 said:
I suffer from some kind of ghost shiting on the second (28t) of a SRAM 7.0 cogset but I've heard that is kinda common and hadn't heard about a fix. Seriously not a problem with it being 9sp.
Interesting, I am suffering from skipping under a load on my 3rd cog (24t). I have a 2003 XT crank, SC Blur, sram 9.0 cassette and HG93 chain. I've suffered from this on 2 different cassettes and chains.

Why would this only happen in 1 gear? It happens regardless of the from chainring also.
The cassette has less than 300 miles on it and was replaced with a new chain, too. I lube and clean every ride. I cannot seem to see anything wrong with the cassette and a friend just realigned my read hanger. It was out of whack, but is now fixed.

So - why does this happen??? :confused:
 

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It could be that a single cog is bent.This has been my problem with every single 9-speed cassette I have ever owned. usually the 8+9th largest cogs bend. I tried a SRAM cassette recently hoping they would fair better, but after 2 rides the 30t was way bent. The cogs are simply too thin and don't have enough support to withstand aggressive riding. I'm 175lbs, ride FR and XC in washington and BC, have 2 bikes with 6month old drivetrains, and was a mechanic in 2 shops for a total of 6 years- so I know it's the cassettes, not the rider or other equipment. this is not a new problem.

A few other observations:
-shimano cable housing has gone from 5mm to 3.5mm with plastic ferrules. They suck when new and only get worse fast in muddy conditions. WTF?
-Shimano has recognized their design flaws and now cassette spiders are 5-arm instead of 4-arm. Too bad they're almost 2x as expensive now.
-While mountain biking in general seems to be evolving towards more aggressive riding, with heavier and more durable parts, shimano continues to make their parts lighter, more high maintenance, and more integration which means more $$ when you break something. How many people are going to be stoked to bleed their brakes and spend $270 everytime they brake an integrated shifter?
-Finally, we saw many of the same type of problems after suntour folded, but before SRAM entered the picture. I think shimano basically needs strong competition to keep them in check, otherwise we'd be riding the silliest crap they could possibly design.

Shimano needs to wake up and realize that the sport has evolved away from their design philosophy. We want 8-speed with thick, durable cogs chains and chainrings, non-integrated shifters, 6-bolt IS disc mounting, and 5mm cable housing. Now that 6lbs+ is the norm for FS frames and trail riding, people aren't concerned about adding 1/4lb to their drivetrains in order to reduce maintenance and improve performance.

Jesterrider said:
Why would this only happen in 1 gear? It happens regardless of the from chainring also.
The cassette has less than 300 miles on it and was replaced with a new chain, too. I lube and clean every ride. I cannot seem to see anything wrong with the cassette and a friend just realigned my read hanger. It was out of whack, but is now fixed.

So - why does this happen??? :confused:
 
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