SRAM hydraulic road shifter compatibility with Shimano XTR

[Fatbiker]

Hi guys,

I am planning on doing something of an 'all road' road/cx build in the near future and I am currently thinking about options for the drive train. Although I wasn't a big fan of disc brakes on road bikes at first, it does seem to make sense to use them on an road/cx bike. Definitely now both SRAM and Shimano have come out with hydraulic levers.

Since I would like to keep my drivetrain mechanical (at least for now), SRAM hydralic levers are the way to go. Unfortunately SRAM road shifters don't work with their mountain bike derailleurs, due to different pull ratios. If I am correct, Shimano Dynasys derailleurs do use the same pull ratio (1:1) as SRAM road shifters. Does this mean it is possible to combine the two? I suppose it isn't possible to mate Shimano XTR disc calipers to SRAM hydralic road shifters, right?

Thanks!

[knef]

They don't mix.
Avid: dot oil
Shimano: mineral oil

[deek]

SRAM mountain and road derailleurs ARE interchangeable (10s anyway, not sure about 11s). Shimano's 10s aren't. I think their 9s might be though?

[Briscoelab]

Just to reiterate: 1. Sram and shimano hydro systems aren't compatible. 2. Sram MTB and Road 10 speed ders work interchangeably. (a big plus over shimano, ATMO)

[grover]

You're better off using a WiFli road rear derailleur. These have the capacity for a 32T cassette cog. While in theory SRAMs 10 speed MTB derailleurs should work with their 10 speed road shifters in practice they're just not 100%. Unless you really want to use a 34 or 36 tooth cassette just use a WiFli derailleur.

[MichaelB]

Just to reiterate: 1. Sram and shimano hydro systems aren't compatible. 2. Sram MTB and Road 10 speed ders work interchangeably. (a big plus over shimano, ATMO)

That can be easily remedied though if you are determined.

I have just swapped over the seals in a pair of Avid X0 Trail calipers so they are compatible with Mineral oil. Pretty simple really and found a local supplier that will make custom seals pretty cheap.

Biggest thing to determine though is the relative sizes of the caliper pistons and master cyl piston sizes, so they match properly and will have the same function curve.

[DaveS]

FWIW, SRAM road shifters do NOT have a 1:1 pull ratio. They pull 3mm of cable for every shift and that produces a RD travel of 3.95mm.

[Briscoelab]

Along DaveS's lines, the Sram 9 speed MTB parts were 1:1. The new stuff is the same as their road system.

I've used X0 and X9 type 2 rear ders on CX bike setups (for better chain retention) with zero issues. The short cage ones work great, but do require a bit more lever force.

[Fatbiker]

I am just thinking out loud here, but do you think it is possible to combine the new SRAM 22 shifters to a SRAM X11 rear derailleur?

If I could get my hands on a 48 or 50 single speed chain ring, that would mean I could have the same gear ratio with 1 front ring, compared to a normal 2 ring setup...

[grover]

Along DaveS's lines, the Sram 9 speed MTB parts were 1:1. The new stuff is the same as their road system.

I've used X0 and X9 type 2 rear ders on CX bike setups (for better chain retention) with zero issues. The short cage ones work great, but do require a bit more lever force.

What cassette range have you used with these setups? I'm wondering if you've had ok shifting with type 2 mtb derailleurs on cassettes with biggest cog 26/27/28.