# Ultegra CS-6700 or Sram PG-1070?



## pelufo

I have a 10sp DA 7800 drivetrain with the exception of a Sram Red compact crankset I just installed. Was running 12-25 but want to go 11-28. My shifting right now is crisp, reliable, and silent. I know historically that is not always the case for SRAM, but does anyone have experience with the PG-1070 cassette vs CS-6700? I I'm not sure where these two stand toe to toe at this point. My current cassette is ultegra for whatever that's worth. Thanks for the input!


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## DaveT

I've had both cassettes and they both work fine. The SRAM will be moderately noisier.


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## pelufo

*PG-1070 cassette vs CS-6700*

Thanks Dave. I guess I have a bigger problem in that apparently a DA 7800RD can only take up to 27. That changes things for me, since I'm only finding 11-27 in 105 or DA.


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## DaveT

pelufo said:


> Thanks Dave. I guess I have a bigger problem in that apparently a DA 7800RD can only take up to 27. That changes things for me, since I'm only finding 11-27 in 105 or DA.


*Most likely* your 7800 derailleur will handle the extra tooth of an 11-28 with an adjustment of the B screw. If you have a friend that has the 11-28 on his wheel, swap wheels to be able to judge for yourself.


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## pelufo

*7800RD w/ 11-28*

Thanks, I'll give it a try.


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## frdfandc

Shimano rear derailleurs have a little play in the gearing size. An 11-28 will work fine with the 7800 RD. You'll probably need to adjust the B-tension screw, but that should be it.

The engineers at Shimano are a stubborn bunch. They only state the product will only work how it was originally designed. If you call Shimano and ask them, they only read off the engineers tech docs.

Example.

To run an Ultegra 6700 triple, you are required (by Shimano) to use the Ultegra 6600 chain. I called Shimano and got the "its because the engineers said so" reply. No specific reason. But I'd be willing to bet that the 6700 chain would work just fine because its just a smaller gear. There is nothing on the 6700 chain design that would prevent the shift from happening at at. 

IMO, I think the new design would help with a triple in the front shifting.


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## GDTRFB

I run a PG-1070 (12-28), a 105 5700 (11-28) and an Ultegra 6700 (11-28) on different wheels with my Force drivetrain.

I like the Shimano cassettes better, but not by much. 

The only time that I notice a difference is when I cross-chain (50 & 28) or come close to cross-chaining (only with the 50, not the 34).

I use a Shimano 6700 chain, and I have used a KMC-XL10 as well as SRAM 1091-r & 1070.
The cassettes shift best with the KMC, the 6700 is a very close second, the 1091-r was very good (but needed frequent lube to stay quiet) and the 1070 was awful.

I'd go with a 6700 or 5700, and a KMC chain.


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