# SRAM Red Chain Skipping Problem



## capnqwest (Aug 26, 2002)

I recently replaced my chain (PC-1091R), Cassette (PG-1071) and the chainrings on my SRAM Red crank. I made the chain the exact same length as the one I replaced. On the stand, the bike shifts into each gear perfectly, up and down the block, all day. The chain has no kinks and I even took a video with a HD slow motion cam but saw no issues with the chain running through the derailler.

When I put signification pressure (250+ watts), the chain will skip on the same cog. It never slips to a different cog just skips in the same place. The issue caused me to get dropped on the opening climb of a road race yesterday and I can't, for the life of me figure out what the issue is.

Any ideas?


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## topflightpro (Nov 3, 2004)

Are any cogs bent?

I have had issues with Sram cassettes where one tooth is bent, causing the chain to hop on that one cog. In one case, it was so bad, we had to send the cassette back. 

The replacement cassette was not perfect, but if adjusted properly works.


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## Kerry Irons (Feb 25, 2002)

*Connecting link?*



capnqwest said:


> I recently replaced my chain (PC-1091R), Cassette (PG-1071) and the chainrings on my SRAM Red crank. I made the chain the exact same length as the one I replaced. On the stand, the bike shifts into each gear perfectly, up and down the block, all day. The chain has no kinks and I even took a video with a HD slow motion cam but saw no issues with the chain running through the derailler.
> 
> When I put signification pressure (250+ watts), the chain will skip on the same cog. It never slips to a different cog just skips in the same place. The issue caused me to get dropped on the opening climb of a road race yesterday and I can't, for the life of me figure out what the issue is.
> 
> Any ideas?


Is it possible that you used a connecting link and that the link is installed upside down? Which cog results in the skipping?


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## frdfandc (Nov 27, 2007)

Make sure that the Powerlink is fully engaged. If its only partially locked, then it will skip in the same spot, regardless of what gear your in.


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## cxwrench (Nov 9, 2004)

frdfandc said:


> Make sure that the Powerlink is fully engaged. If its only partially locked, then it will skip in the same spot, regardless of what gear your in.


i'm pretty sure that if he's putting down more than 250w the link will lock...


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## capnqwest (Aug 26, 2002)

Hi all and thanks. The PowerLink is fully engaged and it's hard to see where it is skipping since it only happens under power. It will also skip on all cogs under power. I guess it's possible I installed the PowerLink upside down as I didn't know that was even possible! I will install a new one and report back.


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## wim (Feb 28, 2005)

capnqwest said:


> I guess it's possible I installed the PowerLink upside down as I didn't know that was even possible! I will install a new one and report back.


Actually, I don't think it's possible to install a SRAM PowerLink (9-speed) or SRAM PowerLock (10-speed) upside down. (But it is possible to do that with the Wippermann Connex link.)


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## PlatyPius (Feb 1, 2009)

There is no "upside-down" to a Powerlink, only to a Wipperman Connex.

Aside from a stiff link, a bent link, poor adjustment of the derailleur, or odd alignment of Mars and Jupiter, I can't imagine what could make the chain jump in all gears.


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## jb20th (Jul 12, 2010)

*Your Chain*

You have to clean the packing grease off those chains, the grease can make the chain do 
tons off weird things Goodluck


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## PlatyPius (Feb 1, 2009)

jb20th said:


> You have to clean the packing grease off those chains, the grease can make the chain do
> tons off weird things Goodluck


You're kidding, right?

That "packing grease" is the best chain lube the chain will ever see.


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## jb20th (Jul 12, 2010)

Actually no I am not it is heavy sticky mess, and if you read the chain package it says to clean it as it effects shifting. I am trying to help a member any advice helps
I also just put that chain on my bike and cleaning it cleared up a lot of problems.


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## capnqwest (Aug 26, 2002)

The chain is clean and has been lubed (I change my chain about 6 times a year so this isn't new to me). Derailleur adjustment seems to be good as shifting is swift and crisp up and down the block in both chainrings. Since there is no backwards/forwards to a PowerLink, the only thing I can think of is that I have an extra link. I'd be surprised though since the chain has the same number of links as the chain I removed but it's the only possible explanation at this point.


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## cxwrench (Nov 9, 2004)

PlatyPius said:


> You're kidding, right?
> 
> That "packing grease" is the best chain lube the chain will ever see.


the stuff that comes on sram chains is pretty nasty, i think it attracts more sh*t than any other lube i've ever seen. i soak all of our new chains in the tank before i put 'em on.


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## capnqwest (Aug 26, 2002)

B-screw. Gave it a full, counterclockwise turn and the problem went away. Odd, since I haven't touched that thing since the day I built the bike but whatever! Thanks for your replies.


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## shoegazer (Nov 2, 2007)

I've been having this exact same problem. Everything tuned, cleaned & lubed but it'll skip.
I'll try your B screw trick - thanks for posting - timely for me!


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## looigi (Nov 24, 2010)

PlatyPius said:


> There is no "upside-down" to a Powerlink.


There is a front and back though on the 10 speed link. There is an arrow on the link halves that show the direction of travel. The side you see from the right side of the bike should have the arrow pointing in the direction of chain travel. This only has a very minor effect on shifting when you happen to shift when that link is participating.


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## looigi (Nov 24, 2010)

cxwrench said:


> the stuff that comes on sram chains is pretty nasty, i think it attracts more sh*t than any other lube i've ever seen..


pshaw. Lube can't "attract" anything. Stuff that hits it might stick though. If it bothers you, simply wipe off the exterior of a new chain with a rag wetted with WD40 or some other lightweight lube. This leaves the good stuff in the links where it's needed.


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## capnqwest (Aug 26, 2002)

Shoegazer, Check out this page: http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur for some tips.



> "SRAM® Derailleurs
> Sram® designates a 6mm between the largest rear cog and the upper pulley. Use a 6mm hex wrench to help estimate this gap."



I didn't know that and it fixed my issue.


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## cxwrench (Nov 9, 2004)

looigi said:


> pshaw. Lube can't "attract" anything. Stuff that hits it might stick though. If it bothers you, simply wipe off the exterior of a new chain with a rag wetted with WD40 or some other lightweight lube. This leaves the good stuff in the links where it's needed.


fine...more shi*t sticks to the lube that is factory applied to sram chains than anything else i've seen...and it is 'stickier'...no it doesn't suck stuff up off the road.


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## PlatyPius (Feb 1, 2009)

looigi said:


> pshaw. Lube can't "attract" anything. Stuff that hits it might stick though. If it bothers you, simply wipe off the exterior of a new chain with a rag wetted with WD40 or some other lightweight lube. This leaves the good stuff in the links where it's needed.


That's what I do. I wipe the outside of the chain with T9, leaving the gooey goodness in the rollers intact.


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## shoegazer (Nov 2, 2007)

capnqwest said:


> Shoegazer, Check out this page: http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur for some tips.
> I didn't know that and it fixed my issue.


Many, many thanks Cap'n Qwest - this totally fixed my issue as well! 
Chapeau!


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## jrz1 (Mar 15, 2006)

B screw did the trick for me also. I replaced an old kmc x10 sl chain with a new one on my bike with Sram Red shifter and rear derailleur and all of a sudden with the new chain I had some slipping under load in some gears. Cassette teeth were not worn so I couldn't figure it out. Closed the gap with a B screw adjustment and problem solved!


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## carbonite (May 30, 2004)

I tried the B-limit screw adjustment but it didnt work. However i am runnning DURA ACE 7900 chain and DURA ACE 10 speed deraileur. SRAM Red 11-26 cassette. Do you alls think it just doesnt like SHIMANO. Does this cassette ONLY run on Red Derailleur? it shifts up and down the gears just fine though, but it just does that tooth skip. and that was with the B-Limit at max,min and in the middle? I really lilke the SRAM Red cassette, am i just outa luck? thanks


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## looigi (Nov 24, 2010)

I've run DA chains (and SRAM chains) on two Red cassettes without any problems. Only skipping I ever got was using a new chain on an overly worn cassette. This skipping is caused by worn cog teeth meshing poorly with the chain. The rear derailleur does not affect this.


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## thalo (Jul 17, 2011)

have you checked to see if the derailleur hanger is secured tightly? I had a similar situation and it was because one (or both) of the bolts was loose. It caused the hanger to move a bit and put the derailleur out of alignment while peddling. Tightened it up and was good to go.


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