Being somewhat anal retentive about my maintenance schedules, I tend to rotate several chains every 2500 miles or so in order to extend the life of my cogs and chainrings as much as possible. So when it came time to rotate my chain this spring, I realized that I didn't have another fresh chain to replace the current one. I typically run a Dura Ace 7900 chain on an Ultegra or Dura Ace cassette, which I have found to be among the best shifting combinations available on the market today. After hearing so many good things about KMC chains (including their phenomenal wear resistance) I pondered the idea of going with a KMC this time. What I ended up with at the end of the day was the KMC equivalent of Dura Ace: the KMC X10SL DLC.
After putting about 2500 miles on it, here are my impressions (after the jump):
KMC X10SL Vs. Shimano
Even though a large number of Shimano chains are actually produced by KMC, these are two different chains, two different technologies. Shimano's 7900 series chain is heavily sculpted and asymmetrical: the sculpting on the side plates is designed to work with the ramps and pins on the chainrings and cassette to help move the chain around more quickly and smoothly. The KMC, in contrast, is a symmetrical chain with no sculpting. Both the inner and outer plates are hollow, and the outer plates are shaped with X-Bridge technology which supposedly helps increase shift speed and precision. Pins are riveted with “Lat Step” processing, supposedly using 350Kg of force to seal the plates together (and making what is claimed the strongest chain connection on the market.) These hollow inner and outer plates, along with hollow pins allow for 239 gram weight for a 116 link chain, and the whole chain (supposedly) has a longer life due to precise manufacturing tolerances and X-SP friction reducing coating.
What makes, the [easyazon_link identifier=”B00629T4X2″ locale=”US” nw=”y” tag=”taicoaandthed-20″]KMC X10SL DLC[/easyazon_link] special is the process in which the chain is treated with KMC's Diamond Like Coating. This super hard, highly wear resistant coating is designed to reduce wear to the plates and rollers, extending chain life (and looking pretty boss with black “stealth” or red powdercoating on the pins and inner plates.) An included KMC Missing Link tool-less chain link connector (in matched colors, which is quite nice) ties the whole thing together, literally. But with all that technology in something as simple as a chain, how does it stack up against the other top end offerings?
KMC X10SL Installation
For a chain that retails for $130, it certainly looks the part. It comes in a nicely appointed box (seen above the jump) along with the color matched Missing Link tool-less connector. Installation was straightforward as with any chain: size the chain out using the “big/big+2” method and then cut it with a chain tool where appropriate. Take special note that you'll need two inner plate ends in order to use the Missing Link (not a problem for me as all my chains use them and I'm used to remembering that fact.) The pin I removed to cut the chain to size did seem to require more effort to push out than the comparable Shimano chain it replaced. Unfortunately, without rigging up some sort of torque wrench to the chain tool, there's not much way to quantify this. With the chain threaded through the derailleurs and around the small cog and chainring, it was time to install the Missing Link.
Tool-less my ass.
Using all my might, I couldn't manage to snap the missing link closed. I finally resorted to getting the Missing Link “started”, that is to get it to the point where all it needed to seat is force, rotating it to the top run of chain, putting the bike on the floor with the rear brake applied and standing on the pedal. This used the force of the chainring and crank arm to lock the Missing Link down. God forbid I ever have to get it open on the road, I'm probably SOL. In the past, Missing Links have been tough initially to open and close, but this fades after a couple uses. This one was particularly difficult to snap closed, but it's really the only time I've had this problem, even with other DLC chains. I suspect the coating on this particular chain made it just that much tougher.
KMC X10SL Impressions
First of all, the black/red color combo matches my 585 and looks boss with the SRAM Red components. Rear shifting in the stand was about the same as the Dura Ace chain it replaced, even if it was a little bit noisier. Front shifting was the same as well.
Out on the road, I found that rear shifting was basically the same as the Dura Ace 7900 model. Front shifting seemed to be slightly improved from the Dura Ace model. My suspicion is that the difference has to do with the symmetrical vs asymmetrical design: I'm guessing that since the asymmetrical Dura Ace chain is optimized to work with Shimano chainrings, the different ramps and pins on my Red rings don't afford the same perfect shift. With the KMC X10SL, front shifts seem to be more precise, and I've not encountered any hesitation on downshifting like the Dura Ace chain had.
The only real downside I was able to discern is that the KMC chain was slightly louder than the Dura Ace, which I attributed to the fact that I was simply working through the factory lube and had not yet given it the Chain-L No. 5 treatment yet. As I suspected, once I applied my lube of choice, the KMC quieted down significantly, although it remains slightly louder than the Dura Ace chain. The increase in noise is nothing spectacular, just a low buzzing when in the more cross chained gears whereas the Dura Ace was silent until the drivetrain was in extreme cross-chain combinations (think big ring/big cog combo.) The other downside (to the red finish at least) is that it shows grease and dirt quite easily and can look pretty shoddy if it's not wiped down regularly.
Verdict
With the release of Dura Ace 9000 and the switch to 11 speed coming, the price of Dura Ace chains will decrease in the coming few months. If you can find the [easyazon_link identifier=”B00629T4X2″ locale=”US” nw=”y” tag=”taicoaandthed-20″]X10SL DLC for a reasonable price (which you can here)[/easyazon_link], certainly consider it. After around 1000 miles on it so far, it's not showing any wear at all, so perhaps all that marketing is true. Still, for the (retail) price of one KMC, you can have a pair of Dura Ace chains. You be the judge if a little longer lasting is worth it to you and if the color choice is worth the premium.
For me, it definitely is.
