Apex and Force compatability
 

I asked this in the bike mechanics section and got no response, so I'll try here too.

I have a Nashbar bike with Force components and I bought a 2011 Specialized Roubaix Elite with Apex today. I know the compact chain rings are interchangable so I plan on swapping the BB and crankset. The shifters are interchangable so I will do that too.

My question has to do with the RD. For the RD I know I need the longer cage for the 11/32 cassette, but can I just use the medium cage from the Apex RD and put it on the Force RD?

nothing? Not even a "you are an idiot to even think about this"

how about buy a Sram Force Wifli RD, and sell the regular Force RD?

Failing that, I bet you can take the longer cage from the APex and put it on the force, which is essentially what a Force Wifli RD appears to be.

Having never disassembled a Sram RD, Can't say for a fact it can be done, or how hard it is to do so.

I do know people have hacked Shimano rd's like this.

Switch the whole Apex rear derailleur over, or buy the Force medium cage derailleur. Or buy a Rival med cage RD. Or an appropriate Sram mountain RD.

I can't imagine a scenario in which building a Frankenstein RD would be preferable to any of these options. If you want to stay Force for the bling factor, you could get at least very close to even money on swapping the RD out. Heck, you might even be able to make a few bucks on the swap if you're lucky.

I am pretty sure that I read something on the SRAM website that said all SRAM parts are completely serviceable. I would take that as meaning completely able to be dissasembled and reassembled. So provided that the basic design of the rd's are the same and I am sure they are you should be able to do this. I can recall a thread were one bf member did this with a shimano rd so I am sure you would be able to do it with your SRAM ones.

That being said it may prove to be easier to just buy a rd that already meets your requirements than to run the risk of taking two working ones apart and possibly ruining one or both. Selling one or both off and then purchasing the proper one would be my first solution. But if if its more of acuriousity thing give it a go.