Bikerumor Shimano Chainwear Challenge: The Results

I’ve never been so happy to wear out a chain in my life. None of us have. It’s weird, but as soon as you have to wear out a chain it becomes this thing that you have to do that just kind of hangs around like a chore. Oh, can’t ride that new bike, have to ride this one. Can’t go for a road ride, need miles on the mountain bike. Ok, ok, it wasn’t that bad – I mean we were riding bikes, which is awesome. We were also riding bicycles equipped with Shimano’s rad XT mountain bike drivetrains in both 9 and 10 speed variants, all in a scientific-as-possible-but-not-really-all-that-scientific test of which chain would last the longest. It was the most scientific test we could put together, and the relative uniformity of the results seems to validate our methods, somewhat.

What’s most important, is that our test results seem to back up everything Shimano claims – which is even more important as we toe the line into 11 speed (and even 12 speed?). Chains are getting narrower to accommodate more gears in a smaller space, but does that correlate into weaker as well?

See the results of the first, and possibly last BikeRumor Chainwear Challenge after the break.

Bikerumor Shimano Chainwear Challenge: The ResultsThe Setup:

As a refresher, we started the Chainwear Challenge  almost 2 years ago and with the help of Shimano outfitted 6 test bikes with matching Shimano XT Drivetrains. Three bikes were equipped with 9 speed 11-34 cassettes and HG-93 chains, while the 10 speed bikes were given 11-36 XT cassettes and HG-94 chains. All bikes were also set up with new cranksets to ensure equal wear on the chainrings and new cables and housings across the board so shifting issues wouldn’t keep anyone from shifting. In hopes of keeping variables as low as possible, all bikes but one were Trek Fuel EX models.

Bikerumor Shimano Chainwear Challenge: The Results Bikerumor Shimano Chainwear Challenge: The Results

Yes, I continue to make ridiculous faces when my wheels leave the ground – I’m working on it. Eduardo however, has it down. Also, Pearl Izumi’s new MTB kit is very blue, I know it’s not for everybody, but I like it.

Riders were told to ride as normal, while allowing me to install the parts, adjust, clean, and lubricate chains as needed with Dumonde Tech Original formula, and to stop by for chain measurements every 50-100 miles. When each chain was measured, it was measured in 4 different locations around each chain, and the highest measurement was taken – which turned out to be important as two of the chains had measurements a full tenth apart by the end of the test. Taking one of those lower measurements at face value would have skewed the test. Also, as we mentioned earlier in the testing, for an accurate chain measurement it is very important to clean and lubricate the chain first so that the dirt and contaminates inside the chain don’t affect the measurements. When you’re using a chain wear gauge that measure in 100ths of a millimeter, this is a very important step. Chains were considered to be worn out once they reached 0.8mm of stretch as specified by the Feedback Chain gauge.

As mentioned, the test got off to a bad start thanks to an insane amount of rain that rendered our local trails as useless as a broken derailleur hanger, which is why it has taken so long to complete. This season had much more favorable conditions with some epic riding and plenty of miles to go around.

Bikerumor Shimano Chainwear Challenge: The Results


If you have ever had the chance to listen to a Shimano Technical guru wax poetically about chains, chain construction, and chain wear, then our results probably won’t surprise you. Simply put, the 10 speed chains lasted longer. Quite a bit longer, in fact. Even the difference between the worst performing 10 speed chain and best performing 9 speed chain was still 225 miles. The difference between Bob and Chris (both endurance racers of similar skill and size) was a whopping 470 miles.

While the performance of the 9 speed group was fairly constant, the 10 speed chains seemed to gain a second wind in the last half of their total mileage. They just wouldn’t die – I would tell riders to expect only about 50 more miles, only to have them return 100 miles later and still not be finished.

Once all the chains were finished however, each rider installed a new chain on the used cassette and chainrings to test the level of wear, and the ability of Feedback Sport’s Digital Chain Wear Gauge to detect the point of chain wear where the cassette will still be ok to use. While we wouldn’t pass off the cassettes as new, there was no detectable skipping or shifting issues on the the cassettes with the new chains indicating that they had not been pushed too far. Because of that, Feedback’s gauge gets full marks as one of the most accurate chain gauges we’ve used.

Bikerumor Shimano Chainwear Challenge: The Results

During the entire test, there was only one malfunction if you want to call it that, which was Riley breaking his chain. I wouldn’t say it was the chain’s fault though, as it broke apart after being smashed between a rock and the big ring. We had to cut some links out on the trail to keep things rolling, so we decided to end its test there since we would have had to add links from a different chain to make it long enough which could alter the results. Riley was on pace to have the best score for the 9 speed group, but even then his numbers were no better than the worst 10 speed chain at the time. Riley is also only 125lbs, so he was the light weight of the group by far.

Bikerumor Shimano Chainwear Challenge: The Results


So how did they do it? We’ve spoken with Shimano many times about the durability of their chains, and what thinner chains mean for durability, and the answer is always the same – the new chains are stronger, because they are engineered to be. In fact, Shimano claims the new Dura Ace 11 speed chain is the strongest chain they’ve ever made which means it replaces the XTR Dynasys chain for that honor. In order to make this a reality the new chains are built with tighter manufacturing tolerances, improved plating, and improved design, all of which add up to better shifting, and better durability. Shimano is quick to point out that there is actually very little correlation between chain width and durability, if any. Rather, ultimate durability comes down to the construction of the chain and the layout of the gearing like the wide range of the cassette and narrower range of the crankset on the Dynasys drivetrains.

Does that mean an 11 speed Shimano MTB group is on the horizon? We have no idea, but we’re sure they could do it.


  1. That’s crazy. I, like many other always assume that the thicker 9 speed chain would have outlasted the 10 speed. And oddly enough, the new 10 speed stuff is cheaper than trying to source older 9 speed stuff new.

  2. I’ve been saying this for years and in fact its the reason I use 10 speed Dura Ace chains on my SS…… THEY LAST FOREVER! A “thicker” 9 speed chain does not have thinner plates or pins. The pins are NARROWER bringing the plates slightly closer together. Nothing structurally has changed. In fact, a shorter pin, would make it stronger if anything. Another thing I’d like to point out, (this is also why 10 speed chains work GREAT on 9 speed drive trains), is that with a narrower chain, you have less side to side “slop” on the chain ring/cassette cog, as the thickness of those have not changed, just the profile of the teeth a little. In theory, this may also contribute to a chain wearing less.

    So what is the best chain lube to use………………………

  3. Another strong possibility is that the chain wears less because it has more cogs. A worn cog wears a chain at an accelerated rate. With more cogs, there is greater possibility that the chain is running on a fresher cog, than one with lesser numbers.

    • @Kenny, good question – it was mentioned in the previous installments, but I should have mentioned it here. Yes, we used the .8mm of stretch specified on the chainwear gauge as worn out.

    • @Greg@dsw, in theory, you are correct. However, in practice it doesn’t seem to make a difference. How do we know? Shimano provided us with a TL-CN41 to use in conjunction with the Feedback gauge and their results were almost completely identical. Perhaps the Shimano TL-CN41 style tool is slightly more accurate, however in our testing it wouldn’t have changed the results.

  4. I haven’t had so much good luck with my Shimano chains. The stock shimano 9 spd chain on my ’06 KHS AM2000 broke within the first 3 months. riding about 30 miles a week. Then on my ’10 Yeti 575 the Shimano 10 spd chain broke within the first 3 months. at 30 miile per week average. Ironically both broke at the same spot on my local trail on a steep climb.

    Looking back, shifting under load probably caused the breakage. I recalll shifting into the granny 36 gear during the climb. The chain kinked and broke. The new Shimano 10spd system does shift smoother and will shift under load. I now try to shift into lower gear before the steep sections rather than waiting until I lug down and shift late.

    I replaced the Shimano chains with a KMC chain, and have no breakages.

  5. Now, if they just took all that technology developed for 10sp, and applied it to an 8sp chain (which is all what a mountain bike needs) – they will last for the life of a bike.

    Give me 10-38 in 8 speed. To run with one front ring.

  6. i’m sold. been abusing a 10sp chain on a well worn road cassette fitted to my mtb bike. pretty hearty set up with shadow plus.

  7. This is not about being “retro”. 8sp shifts better in mud. You do not need as many gears on a mountain bike as on the road. And the only reason 9sp is weaker, is that they did not apply new tech to older chains. Simple things like newly shaped asymmetrical plates reducing stress on chain when shifting.

    • @Mindless, not necessarily. Part of the chain lasting longer is the wide range of the rear cassette. In order to build an 8 speed cassette with a similar range you would need to use larger jumps somewhere in the range between gears. Larger jumps could put more stress on the chain as it shifts. Also, one of the benefits to having more gears with a wider range is that you are more likely to find the proper gear ratio rather than being under or over geared for the particular incline you are riding. It’s possible that it might not make that big of difference, but there is reason to having more gears.

  8. @Greg Even if the tool is out of calibration, all the measurements would have been made “out of calibration”, thus all the results would still be comparable to each other. The results still stand.
    I ran a 10 spd XTR drivetrain for almost 2000 miles(mostly endurance races; rider weight about 175lbs) before replacement and never had a problem until the teeth were all so warped that the thing was chainsucking. Replaced it again with all 10 spd. No issues.

  9. I find the “One more cog justifies a drivetrain replacement” mentality to be a highly hypocritical strategy for the cycling industry to embrace. It is certainly better now that SRAM is making Shimano-compatible components rather than not so long ago when Shimano would aggressively obsolete components from the top down forcing you to either replace your drivetrain entirely or end up riding comfort-bike level components.

  10. I find these results quite accurate. I have always run a 10spd chain with my 9spd drive trains. It started with my old Cannondale Scalpel. It suffered from ghost shifting from the rear end torquing around, no matter with I did with adjustment. Using a 10spd chain allowed more clearance between gears, curing the ghost shifting, and making my drive train last longer. Even after switching to a Niner hardtail, I continued with using a 10spd chain. I have found that it allows for a wider gear range in the back before you have to switch gears up front. I know this isn’t always best, but neither is shifting from the big ring to small ring on a hill.

  11. @g – @vhom is correct for some parts. M670 SLX 10 speed stuff is generally (slightly) cheaper than M660 SLX 9 speed. M980 XTR 10 speed is cheaper than M970 XTR 9 speed.

    Thats usually true for shifters/derailleurs. Not necessarily chains/cassettes though.

  12. Wouldn’t there be less wear with a 11-36 cassette? I mean, is it the chain or the gearing range (and extra gear) that allows the chain to last longer?

    • @Jeff, since the 10 speed cranks have different chain rings 22 v 24, 42 v 44, Shimano claimed the difference in cassettes would be offset.

  13. being a strong SS rider i have run the whole gamut of chains(even belts). the strongest chain is the nickle chains or for the material than the design.

    i am thinking that shimano is making their new 11 speed chains of better material and design. that is the reason they are lasting not the size. they cost more and “should’ last longer. but not all costly chains last any longer. kmc, sram…….yes they are lighter but not more durable.

    maintenance can make any chain outlast a better chain as well. clean and wax, check gears/cogs for wear.

  14. @g, possibly, but we’re discussing Shimano. With Shimano it depends what chains you are looking at. Currently there is a big difference between HG -73 and HG-74 chains (29.99 vs 44.99), yet the HG-93 vs HG-94 are identical at $54.99. And while there is a big difference again between CN-7701 and the 10 speed XTR CN-M980, Shimano has kept the price of the new 11 speed CN-9000 the same price as the 10 speed DA Cn-7901.That is of course buying new chains from QBP and selling at MRSP – dealers may have older stock that was purchased a cheaper prices. Clearly there are some discrepancies, but you have to give Shimano credit for keeping many of the prices the same in spite of the new technology.

  15. Why do people care so much about how their mountain bike shifts in the mud. You guys are aware that this isn’t 1995, and we now know that you shouldn’t be riding muddy trails, right? You know that that causes massive erosion and ruins the trails for others, right?

  16. Current generation XTR 9 speed (which is still available) is indeed more expensive than it’s 10 speed counterpart. I manage a LBS, and at least in Canada and The U.S 9 speed runs about 5-10% more for most parts than 10.

  17. Fair enough guys, but I use Sram chains for my shimano drivetrains, as they’re cheaper, the powerlink is useful, and I think they’re at least as reliable. And with the sram chains, the 9 speed is definitely cheaper.

    Also, I second what bc said.

    • Drive trains were kept free of large debris, and dried dirt/mud was brushed off with a grunge brush. Each time a chain needed to be lubricated, they were run through a soapy rag to remove any exterior dirt, and then lubed with Dumonde, 1 drop per roller, exactly as recommended. Bikes were not powerwashed/hosed and no other methods of cleaning were used.

  18. -@BC.

    your point is only valid for the dusty regions where rain is the exception, not the rule.

    where we ride, it rains every month of the year, and if we took a pause when it was muddy the trail would be closed and over grown when we got back.

    get over it.

  19. I have over 2000km on my current XT 10spd setup and the chain is still within wear tollerances, no signs of failing. Planning to replace soon just to be on in the safe side. Cassette and front cogs are worn, but serviceable too, may not get another 2000km out of them but they’ll last for a while yet.

    All this riding has been done on mixed trails and conditions ranging from dry and dusty to sandy loam to outright slop.

    Regular cleaning and lube is the biggest differentiator in chain life I reckon.

  20. My LBS told me to stop using soap for chain cleaning. I also stopped using a wax (Squirt). It got sticky at some point during the ride and caused some serious chainsuck.

    Now I use normal Shimano chain PTFE oil for lubracation and Hope Sh*t Shifter for cleaning. It works a lot better.

  21. It seems that Shimano has changed chain design and durability between the 9 and 10 speed stuff. If they made the 9 speed to the newer standards… that may be a better test?
    Also, did you guy’s measure the actual lengths of the chains to begin with? Or just rely on when they were worn? This may be the difference I’m talking about?

  22. I can get 2-3000 miles out of my Shimano 9 speed chains. I’ve also measured wear differences between lower models like HG53 and XTR/Dura Ace and there’s no difference at all, I guess the pretty plating that stops it rusting is the only difference. Keep your chain oiled and there’s no difference.
    I won’t be splashing out £230 for a few more miles out of a 30 quid chain…

  23. My question would be

    Which is more durable chain? The 7701 or HG94?

    They are about the same price. I am sure the 7901(xtr10sp) is better than 7701(xtr9sp) but I doubt it’s twice as durable or better shifting. The price is nearly double.

    So is the HG94’s better engineering etc make it a better value than 7701?

  24. This is nothing revolutionary. The actual cross thickness of the chains laterally, differ in that the 9 speed has a longer through pin than the 10 speed. The stretch of a chain is MOSTLY a result of the through pin bending. Ever tried to bend a short stick? It’s physically harder than bending a long one. Hardly revolutionary, but physically expected if you look at the difference.

  25. What this review misses out is that the better constructed 10 speed chains are also a lot more expensive. hg 93(9 speed) vs. hs 94 (10 speed) – is getting on for double the price. For just a bit more longer lasting that is NOT worth it.

    Fact is, identical 9 speed chains wear less !! It’s basic mechanics. You can pay a lot more to have more durable chains, but that’s missing the point here.

    That’s why this is a poor review in my eyes it missed the point !

  26. I have an 8 speed KMC chain on a single speed Cross bike that has been abused beyond belief by my tendency to do a ton of hill climbing in muddy conditions, I figure it has about 1300 miles on it and still isn’t worn enough to merit replacing yet. I clean it about every 3 or four rides, and the average ride for me is about 35 miles. Factors such as how much grit, how often the chain is cleaned, what kind of lube and how much lube you use vs. the average amount of force exerted on the chain weigh in on the life span of a chain. The number of speeds and thickness of links is arbitrary to durability. It really only matters how well you care for it, and how hard you ride. If you ride like a grandma, any chain will last you years, but if you ride over mountains off road on a regular basis, you will need a new chain pretty quick. Take it from a guy who has spent 35 years riding about 100 miles a week, my advice is to buy a high quality chain from a reputable manufacturer that is the proper type for your setup, keep it clean and lubed enough that you don’t hear it squeak, buy a Park Tool CC-3.2 gauge (because they are cheap and work as well as anything on earth), and as soon as the 0.5 side drops in, get a new chain. Wipperman or KMC make the best performing chains.

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