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Slippage on XTR components?

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PostPosted: Wed Apr 28, 2004 7:55 am GMT +0000    Post subject: Slippage on XTR components? Reply with quote

*** REPOST from Technical forum - Sorry! ***


I just go into MB'ing and have been going off of what all my MB'ing friends have told me. Yesterday, I bought a pre-owned Kona Explosif with all XTR components (for a song). Last night I took it out and rode on some pretty extreme off road conditions and the gears seemed to slip when going up really tough hills. I thought that by buying the best components available, I wouldn't have any problems with shifters/gears/whatever.

Do all bikes do this or do I just need to have it adjusted/fixed?


- Wil
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The Bike Doc

Joined: 08 May 2003
Posts: 1371
Location: Corpus Christi and Warda, Texas

PostPosted: Thu Apr 29, 2004 8:02 pm GMT +0000    Post subject: Reply with quote


You may have problems with a worn chain or a brand now chain on worn cog teeth and chainring teeth.

Lay a 12 inch ruler with the "0" mark centered over a link pin while holding the chain strait. Look at the "12" inch mark. If the center pin is more than 1/8 inch past the "12" mark the chain is excessively worn. Now check the cogs on the rear cassette and the teeth of the chain ring. If they are showing scalloping (concavity torwards the top of the teeth) the cogs/chainring are excessively worn. Look at the chain rings. With the chain on the ring lift up the chain half way aroung it's wrap of the chain ring. You should not see day light. If you see a gap then you have a worn chain and/or chain ring.

Okay, now for the ugly secrets of XTR. The cogs are lighter for a reason and they wear way faster than XT or LX components. The cogs use alloys that are nickle palated on the larger cogs and titanium on the small cogs. The large cogs wear out much more quickly than the steel cogs on XT and lower groups. I have seen the teeth of the large cogs shere off on the 9 speed XTR. (Older 8 speed XTR were made of steel and this was not a problem, this is infact what I use on my personal bikes.) The XTR front derailleur also is made out of nickled plated alloy. One grungy ride and your XTR front derailleur is history. I have replaced a few XTR front derailleurs after wet races. The XT front derailleur uses a steel cage that is substantially more durrable and adds only about 30 grams of weight.

Now another ugly secret about mountain bike 9 speeds groups in gerneral both Shimano and SRAM. They are very intolerant of cable/housing stretch and require freqent readjustments and immaculately clean housing to keep shifting decently. The 8 speed groups have much more tolerance to the demands of off road riding. I got fed up with constantly having to adjust my personal 9 speed groups as well as my rental bike 9 speed groups. I switched them all over to 8 speed groups and have never looked back.

I hope this info helps.

Paul K. Nolan, MD
AKA: The Bike Doc
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PostPosted: Fri Apr 30, 2004 6:44 am GMT +0000    Post subject: Reply with quote

Thank you very much for that very detailed explaination of XTR, chains, and cogs! I like to ride in grungy conditions as much as possible so it looks like I should have gone in a different direction... and saved some money all around. I'll know better next time.

Thanks again,

- Wil
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Joined: 18 Oct 2003
Posts: 94
Location: Downtown Houston

PostPosted: Fri May 07, 2004 8:56 am GMT +0000    Post subject: Reply with quote

In the meantime, wipe down your chain every ride and clean and lube the drive-train every 2-3 rides. This will probably double or triple the life of the stuff. The chain is the most vulnerable and critical part of any bike, so make sure you take care of it first!

Some things to keep in mind whilst one is XTR-bashing:

-Texas has a lot of sand in the soil and sand is really hard on drivetrains.
-XTR is no-compromise, money-is no object performance stuff (ie durablility got bumped down the engineers' goal sheet behind weight and performance)
-XTR is for pro-level performance and therefore requires pro-level cleanliness and maintenence.

My opinion? XT works as well and lasts longer, but it weighs more. I use XTR Cranks/chainrings and front derailleur, an XT cassette and chain, and SRAM X.O shifters and rear derailleur. I thought this to be the best compromize and so far, after a year, I've had zero drive-train problems.

Good luck and keep it CLEAN!
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