SRAM 22/36 double conversion kit: On Test- by c_g
What is the best all-round transmission for 29″ers?
After lots of trial and error the answer, is clear to me: With a chain ring combination of 22/36T in front and a 12-36T cassette, I can cover pretty much everything I usually ride.
Why? A double chain ring combo for me is clearly more effective and less vulnerable to malfunction than triple. In addition. Besides with a 29″er I hardly ever use the large chain ring on triples. Obviously ground clearance is also better with a double.
One can imagine how pleased I was when the 2X-trend began to slowly penetrate with SRAM and Shimano. But disillusionment followed immediately after – as the grannys in most every mass produced double are 26 or 28 teeth – perfect for 26-inch bikes or a fast XC course but definitely too little true “mountain gears” for long alpine ascents with a pack (… at least for me ;))
WHAT TO DO? ? „A conversion to a smaller chain ring does not cost much.“ May be what many will have thought … only to discover that the new doubles mostly come in a 80/120 mm diameter bolt circle which won´t allow smaller grannys. A painful realization for me which many other 29″er riders probably have made.
Remaining are only the options to swap to a new triple crank and take off the large chain ring and exchange the middle against a 36t or to go with one of the smaller, more flexible crank manufacturers like Race Face, e thirteen or such … or simply to build up some extra leg strength ?.
But now there is hope for owners of SRAM-equipped bikes:
SRAM now provides a conversion for X.0 and X.9 cranks (and their OE counterparts) consisting of two chain rings (22/36 or 24/38), a polycarbonate bash guard and a matching spider (64/104 mm) – all pre-assembled in one piece. Euro pricing fort he set is € 89.90 for the X.9 kit and € 99,90 for the X.0 kit. The conversion itself is very simple and possible even for the ‚Workshop dyslexics':
1 Disassemble the crank, by loosening and taking off the left side crank arm (only 8mm hex required) and then slide out the drive side (with axle).
3, Put the new combination in place and tighten the locking screws. (The crank assembly is done in in reverse order.)
Note: After the conversion one usually has to re-adjusted the front dérailleur, since the distances are not perfectly identical. Also, depending on the frame design, the shifting quality can suffer due to the slightly larger gap measure for the front dérailleur. If this were the case, one can refer to one of the specific dérailleurs by SRAM adjusted for those smaller chain rings.
FIRST RIDING IMPRESSIONS: After the conversion, that we have performed on our ROCKY MOUNTAIN Element 970 test platform (time required about 10 min), I noticed a little difficulty in shifting onto the big chain ring, just a tad, but noticeable still. Otherwise the system worked as usual – reliable and accurate. We report if any abnormalities should arise.