# SRAM cassettes PG-1070 vs OG-1070



## royta (May 24, 2008)

My '09 Kestrel came with a full Rival groupo. 50/36 chainrings and a 12-25 OG-1070 cassette. My second chain is measuring 12 1/16" and my cassette is making clicking sounds on the popular cogs. I enjoy a silent drivetrain and have a 206 mile race coming up in three weeks so I'm replacing my cassette, rings, and chain (KMC X10SL).

My question is this...does the PG-1070 shift as well as the old OG-1070? The PG looks like your typical cassette, where the OG has the staggered missing teeth.

Thanks.


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## Ventruck (Mar 9, 2009)

Both do the job. IME with the OpenGlide, performance suffers dramatically upon any wear, whether it be the cassette itself or the chain. Skipping and catching will occur too often at that point.

The PowerGlide (or generally any cassette without missing teeth) will perform more consistently down the line. You could get away with a chain past the ideal wear point and still keep going.

Your OG-1070 is probably not worn out, and only the chain is. It's the same story with my OG-1070, which is now sitting in my parts bin in still-decent condition because I'd hate to be caught dead on a long ride when the chain just happens to be worn.


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## royta (May 24, 2008)

Thanks. I had already ordered the PG, but I still wanted to know. I'd go for the OG-1090 if it came in a 12-25. I don't like the missing 16 in the 11-25.


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## Ventruck (Mar 9, 2009)

royta said:


> Thanks. I had already ordered the PG, but I still wanted to know. I'd go for the OG-1090 if it came in a 12-25. I don't like the missing 16 in the 11-25.


A lot of people don't like the OG-1090 because of noise and the general nature of the OpenGlide setup as I described earlier. Aside from UCI minimum weight concerns, even pro riders would want the PG-1070 to resolve the noise.


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## royta (May 24, 2008)

Sounds good. Obviously it's better to put my ego aside. Thanks.


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## Zen Cyclery (Mar 10, 2009)

The idea of missing teeth on paper makes sense, but weather it actually helps the shifting is arguable. Sram still offers a cassette with missing teeth their "open glide" system it is called the OG-1090. To your point of liking a quite drivetrain, this will be anything but that sense it is a 1 piece hollow design.

I am going to have to disagree with Ventruck in this situation that it is not just your chain. Sense it is only skipping around in select gears and not all of them this would tell me that it is your cassette and or chain that is worn.

-Zane


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## Ventruck (Mar 9, 2009)

Zen Cyclery said:


> I am going to have to disagree with Ventruck in this situation that it is not just your chain. Sense it is only skipping around in select gears and not all of them this would tell me that it is your cassette and or chain that is worn.


No argument intended, but I had the same gears skipping (by those "popular" select gears I assume 15-16-17) with a worn chain, even though I'm spending almost as much time - if not more - in the 19 and 21 instead since I often do climb repeats. Problem would be even more apparent with smaller cogs (the 13 and 12 and I hardly use). I've been able to run my Ultegra for more miles without that issue, through 2.5 chains.

I'm not entirely sure what the theoretical logic would be behind that, though. Combination of chain line and less contact points to mesh into?


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## shoegazer (Nov 2, 2007)

I just replaced my KMC chain & Red cassette last week due to the same symptoms. I replaced the cassette with an Ultegra cassette this time and it's running much more smoothly & whisper quiet. I'm excited to put some milers on it to see if this is the noise/shift solution for me.
As an aside, I did an experiment by filling the Red Cassette with spray foam which did dampen the sound somewhat but there was still noise despite a true, clean chainline.


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## Zen Cyclery (Mar 10, 2009)

Ventruck said:


> Problem would be even more apparent with smaller cogs (the 13 and 12 and I hardly use). I've been able to run my Ultegra for more miles without that issue, through 2.5 chains.
> 
> I'm not entirely sure what the theoretical logic would be behind that, though. Combination of chain line and less contact points to mesh into?


You make a good pint. This would make sense because with the OG cassette not only are you running on a smaller cog but you also have teeth missing. Being a Shimano guy when I have select gears skipping I replace chain and cassette. Like you I go through 2 to 3 chains before this happens.

-Zane


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## royta (May 24, 2008)

I replaced my chainrings, cassette, and chain (KMC X10SL) on Friday evening. I also bought a Park Tool DAG-2 derailleur hanger alignment tool. My drivetrain was whisper quiet and shifts were precise on Saturday's ride. I did notice the PG-1070 would make a "tinny" sound on some of the shifts. No big deal, but it is something I noticed.


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