Thursday, August 27, 2009

Why SRAM Chains Suck

I love SRAM...I use their forks, brakes, cranksets, shifters, and rear derailleur.

But their 9 speed chains suck, and I've dissected them to find out why the break so easily (the only two 9 speed chains I've broken). It comes down to the pins they use. On the SRAM PC 951/971/991 the pin only contacts the plate partially instead of entirely around.
 
The pin actually only contacts the plate on above and below the center ridge...weak. SRAM makes a PC 991 CrossStep that increases the pin strength but its a $45+ chain and it still doesn't completely contact the plate
 
Now compare the KMC and Shimano chains (KMC makes the HG53 and 73 Shimano chains). They use a mushroom center punched pin. You can feel how strong this pin is when your using a chain breaker to size the chain. It takes way more effort to push the pin through. In dissecting KMC X9 and a Shimano HG73, I can feel a distinct ridge around the entire pin. This gives the the KMC and Shimano chains more than 1.75x more pull strength than SRAM
 
  

4 comments:

  1. Interesting post. My rate of failure is about the same for Shimano as for SRAM in the chain department. I think Shimano's shift faster/better. But, in poor weather and mud I find that the link design is prone to developing stiff links. SRAM on the other hand uses basically flat link plates that don't suffer the same fate in poor weather and low lubrication. Also, SRAM can be had for cheaper. Food for thought.

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  2. In my very limited experience with KMC chains I think the reverse is true.

    I had never used KMC chains until recently. I wasn't at all impressed with the rivet holding power of the KMC mounted to my recently purchased used but new-to-me '05 GF Rig SS. I had never, ever had a chain that 'broke' apart so easily with a chaintool. When I discovered how easily it was to 'break' I promptly replaced it with a SRAM.

    FWIW, the only chain I've actually had fail during a ride was a Shimano but I was using Shimano specific rivets & once I stopped doing that I never again broke one.

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  4. Are we talking single speed or multi speed chains...the post is only applicable to multi speed (and for the most part 9 speed) chains

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