Mountain Gear

Tech FAQ: What About 1×9 and 10?

More on mixin' and matchin' drivetrains: SRAM 9 and 10 speeds

Dear Lennard,
Regarding your
earlier article on the various disk brake pad compounds and their uses, I thought I’d add another option.

I’m currently running a mixed set of pads, one side organic, one side metallic, on BB7 brakes. This has proven to be a quiet and effective combination that provides most of the stopping power of all metallic pads, but quieter and with more modulation. True, I did give up some ultimate stopping power, but the increase in modulation more than makes up for it as the brakes are now much more useable.
-Jon

Dear Lennard,
I know from experience that most Shimano drive train parts can be mixed and matched — i.e. 9-speed road shifters with 9-speed mountain derailleurs (on the ‘cross bike); 10-speed road shifters, cassette, and chain with 9-speed derailleurs (on the road bike), etc.

But on to the mountain bike: Right now it’s set up as a typical 3×9, running SRAM X-9. I’m wanting to set up a 1x system, either 9- or 10-speed, hopefully with a 36T cog option. If I were to go with a 10-speed SRAM mountain shifter and cassette, can I still use the X-9 9-speed rear derailleur with this system, or am I roped into buying a new rear derailleur as well?

I know the SRAM XG-999 cassette is another option to get to 36T and stay with a 1×9 setup, but at that price (if you can find it), it’s almost more attractive to just buy into the 10 -speed system, which, I’m sure, is very intentional.  Any experience or suggestions?
-Adam

Dear Adam,
I have not tried that combination of SRAM 10-speed mountain shifter with SRAM 9-speed mountain rear derailleur, but I’m pretty sure it would not work.

The reason I think this is that, unlike Shimano in the 9-speed days, if you wanted a wider range with a SRAM road shifter (which has been 10-speed since its inception), you could not substitute a SRAM 9-speed mountain rear derailleur for the road rear derailleur; the cable pull required differed between the two systems. On the other hand, as you said, you can substitute a Shimano 9-speed mountain rear derailleur onto a Shimano-equipped road bike, either 9-speed or 10-speed, and thus allow the use of a wider-range cogset.

When Shimano went to 10-speed on the mountain bike and introduced Dyna-sys, it lost this cross-compatibility. The only rear derailleur you can use with a Shimano mountain 10-speed shifter is a Shimano mountain 10-speed rear derailleur. So to widen the range of a Shimano-equipped road bike, you’re still stuck with using a Shimano 9-speed rear derailleur.

But when SRAM went to 10-speed on the mountain bike and introduced 2X10, it added compatibility that it had never had. You now can use a SRAM 10-speed mountain rear derailleur with a SRAM road shifter. That doesn’t help you, though. I think you would have to use a SRAM 10-speed rear derailleur to make your setup work.

Before making the purchase, though, you could experiment with clamping the cable on the other side of the cable-fixing bolt on the 9-speed rear derailleur or with putting in a TravelAgent into the system. Either one would change cable pull, and whether it would do it properly so that it would work is another story.
-Lennard

Readers can send brief technical questions directly to Lennard Zinn.

Technical writer Lennard Zinn is a frame builder (www.zinncycles.com), a former U.S. national team rider and author of numerous books on bikes and bike maintenance including the pair of successful maintenance guides “Zinn and the Art of Mountain Bike Maintenance” – now available also on DVD, and “Zinn and the Art of Road Bike Maintenance,” as well as “Zinn and the Art of Triathlon Bikes” and “Zinn’s Cycling Primer: Maintenance Tips and Skill Building for Cyclists.”

Zinn’s regular column is devoted to addressing readers’ technical questions about bikes, their care and feeding and how we as riders can use them as comfortably and efficiently as possible. Readers can send brief technical questions directly to Zinn.

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