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Crawlin' like a Crawfish!
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990

I replaced a 99 chain with 990, wouldn't shift worth a crap. I replaced the cassette too (a 990), still skips around. I never had a problem with the pc-99 chain. I think the new design sucks and I wish someone from SRAM would come on this board and explain why they changed from something that worked perfectly to something that doesn't. :mad:
And by the way, I have no shimano crap on my bike at all, but it doesn't mean I won't go back if these designs continue to be inferior.
 

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zoo00oom said:
I replaced a 99 chain with 990, wouldn't shift worth a crap. I replaced the cassette too (a 990), still skips around. I never had a problem with the pc-99 chain. I think the new design sucks and I wish someone from SRAM would come on this board and explain why they changed from something that worked perfectly to something that doesn't. :mad:
And by the way, I have no shimano crap on my bike at all, but it doesn't mean I won't go back if these designs continue to be inferior.
Same here and the bike now shifts better than ever. 990 is a great chain
 

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zoo00oom said:
I replaced a 99 chain with 990, wouldn't shift worth a crap. I replaced the cassette too (a 990), still skips around. I never had a problem with the pc-99 chain. I think the new design sucks and I wish someone from SRAM would come on this board and explain why they changed from something that worked perfectly to something that doesn't. :mad:
And by the way, I have no shimano crap on my bike at all, but it doesn't mean I won't go back if these designs continue to be inferior.
Whatever is causing your gear skipping certainly isn't your 990 chain, unless it's got a bent link or something in it.
 

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I just replaced my XT cassette and chain with 990's, no problem so far, shifting is excellent.
They were on sale at Jenson a month back.
 

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Crawlin' like a Crawfish!
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certainly was!

uktrailmonster said:
Whatever is causing your gear skipping certainly isn't your 990 chain, unless it's got a bent link or something in it.
The problem was definitely the fault of the new chain design. It should not be thought of as a direct replacement for the 99. I did resolve the problem by completely starting over from scratch. The system shifted flawlessly before.
Removed the der., checked the hanger alignment, checked chain length over the two big rings, and the kicker and what I feel like was the biggest thing was the 'b' adjustment on the derailleur itself. I had to run the screw in alot farther then before(more tension).
The chain must have tighter tolerances than the 99, because there was no room for error. In other words, I wasn't able to just slap a new chain on and go, as was the case before they went to bulging plates design.
It does shift fine now, but I would warn others, if you switch, make sure and do a complete drivetrain tune up at the same time. :rolleyes:
 

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zoo00oom said:
The problem was definitely the fault of the new chain design. It should not be thought of as a direct replacement for the 99. I did resolve the problem by completely starting over from scratch. The system shifted flawlessly before.
Removed the der., checked the hanger alignment, checked chain length over the two big rings, and the kicker and what I feel like was the biggest thing was the 'b' adjustment on the derailleur itself. I had to run the screw in alot farther then before(more tension).
The chain must have tighter tolerances than the 99, because there was no room for error. In other words, I wasn't able to just slap a new chain on and go, as was the case before they went to bulging plates design.
It does shift fine now, but I would warn others, if you switch, make sure and do a complete drivetrain tune up at the same time. :rolleyes:
There you go then, it wasn't the chain, it just needed some adjustment. I'd say that's pretty normal after changing the chain and cassette - I assume both were worn out?
 

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Unshaven Yak
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Jeez, sounds like you turned what is a standard one-time derailer adjustment into a project for yourself. I just changed out a busted hollowpin chain out for a cheaper PC69 and had to adjust the b-tension a bit. Replaced rear derailer hanger and had to adjust high limit screw and indexing (by a full turn and two clicks respectively).

Granted, it took years of experience to be able to pinpoint exactly what the fix is for a badly shifting derailer. I feel for you, but it ain't the chains fault. They were exactly the same length right? That would account for the b-tension requirement.

Also when you do adjust the b-tension screw, be sure to kick the derailer all the way forward when you're done, then ride for a bit through full gear range and with suspension activation (if duallie). That will allow the spring in there to find it's sweet spot and you can judge from there with better accuracy.
 

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The 990 does not have the beveling on the outer faces of the link's that the PC99 has,only two edges of the pin's peaned over, the PC99 has four.
The 990 I fitted two day's ago is now back at the shop as it had a tight link that would not ease up.
I am now trying a Shimano 7701
 
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