1Lieutenant

I own a 2009 Look 566 that I purchased new. Over the years I have done some upgrades. I replaced the SRAM Rival front derailleur with a SRAM Rival yaw version. The wheels were replaced with Shimano RS80 Carbon/aluminum wheels. I now would like to run a larger rear cassette for the hills. The bike is 10 speed and I don’t need or want to go to 11.

is this as easy as replacing the cassette with a 10 speed 11-36 rear cassette, a new long cage SRAM Rival derailleur, and a longer chain? The new SRAM Rival medium or long cage rear derailleurs are listed for 11 speed, but my understanding was that they will work with the 10 speed cassette and the 10 speed shifter.

tFUnK

The older Rival RDs only came in short or medium and the medium had a max cog limit of 32t. I assume you're after the newer Rival RD which can handle 36 or 42t cogs.

I run a 11sp SRAM Rival RD with 10sp Rival shifters. They work fine.

jan230

The new 11 spd rated rear derailleurs will work.
The movement is dictated by the shifter. (and properly set limit screws!)
Should be fine as long as shifters and cassette match at 10 speed.

1Lieutenant

Bought a SRAM GX long cage 2x and 11-36 cassette. Both 10 speeds. Longer chain as well. Will let you know how it goes. Minimal cost to extend the useful life of the bike.

nnnnnnnnnnnnnnn

Hi, I'm also interested in widening my cassettes to 12-30T on some RS80's but note the spec' sheet for the RS80's states that 28T is the largest sprocket size they can be fitted with. So interested to know if it worked out for you?

1Lieutenant

Sorry I didn't update this before!
The SRAM GX long cage derailleur works perfectly with the SRAM Rival brake/shifter levers and 11-36 tooth cassette. I now have a bike that is more suited to steep hills as well as the flats.

HTupolev

Probably just Shimano going a bit overboard in contaminating specifications across components that they market as being related to one another; they wanted people to only use those wheels for road riding, and probably weren't selling >28T cogs in their performance road groupsets at the time.

It doesn't make sense that a 700c road wheel would have any design features precluding sprockets larger than 28T.

nnnnnnnnnnnnnnn

Thanks for that.

On re-reading it I may have miss interpreted the tech' sheet.
It reads:
"In order to realize the best performance, we recommend that the following combination be used.
Applicable tire size Clincher tire 700C (19C - 28C)
Largest sprocket 21 - 28T"

So it doesn't say it won't take >28T, just they don't think it offers the best performance, which nods to your thought that >28T probably wasn't a sprocket size that was being promoted for road bikes back in 2008.

I've moved from London, England to Vermont, USA and the hills are killing me on the 11-25T.