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  1. #1
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    New question here. Did I really go through a chainring in 8 months?

    Hello All,

    I seem to have a problem with my bike that I am unfamiliar with. I don't really know how to accurately judge the wear on a chainring. When comparing the wear to my Granny gear (seldom used) to my second ring (95% of the time used) there is a tremendous difference in the teeth. My bike tends to lose its grip on the chain in a downhill so if I need to pedal immediately off a downhill, the chain will launch off second chainring and jump on to the granny or wrap around the bottom bracket I just don't want to go around and replace parts that still have a good deal of life in them.

    I will get a picture up, the server is too busy now

  2. #2
    bi-winning
    Reputation: rkj__'s Avatar
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    It is very possible to wear out a chainring in 8 months, especially if it is aluminum.
    When under pressure, your level of performance will sink to your level of preparation.


    Shorthills Cycling Club

  3. #3
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    My chain ring

    Also very important, my Crankset is a OEM SR Suntour crank. I am not sure, but it must be made of aluminum. Would it be worth is to replace the rings or just get a new crank. I have already phased most of the OEM stuff off my Trek 4300.
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  4. #4
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    Reputation: Micka's Avatar
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    If it's anything like the OEM Suntour cranks that came on my last bike, it's probably worth replacing the crank. I think the big & middle rings were pinned together rather than bolted (yours looks the same) and my then LBS said they couldn't get a replacement. So new cranks it was.
    Although the way you describe it in the first post, as only coming off after a downhill, it may be a chain tension issue. If however the chain spews off the middle ring whenever you put the power down then the ring is likely worn. Don't forget to replace you chain at the same time - a worn chain will wear out new rings faster.

  5. #5
    All 26.5" all the time!
    Reputation: Zanetti's Avatar
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    The pic is too blurry to tell if it's worn out or not.

    Eight months seems a bit too soon for wearing out a chainring -- even for aluminum...

    ...and I'm afraid to ask ---- when was the last time the chain was measured for wear?





    If the answer is *never* , you might need to replace the crank set, chain and cassette to restore shifting performance.

  6. #6
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    The chain is only about a month old, so I never really though about the chain being the problem. The chain before that lasted 3 months. I replace the chain in the beginning of the season.

  7. #7
    All 26.5" all the time!
    Reputation: Zanetti's Avatar
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    When you say the OEM chain lasted three months.... why was it replaced? Did it measure out more than 2% worn, or did it break?

    If the chain is allowed to wear beyond a certain point, the most used chainrings and rear cogs wear out unusually quickly.

    Here's a link to explain: http://sheldonbrown.com/chains.html#stretch

  8. #8
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    My first chain I used from October, when I bought the bike, until march when I went to a nine speed system from an eight. The next chain got torn up when I broke a derailleur hanger and it was tossed into the spokes. That was in early may. I have been using that third chain ever since.

  9. #9
    All 26.5" all the time!
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    It does seem premature for the middle chainring to be worn out (and I'd bet it's steel by looking at the photo - a magnet will tell for sure), check out the link to Sheldonbrown.com and eyeball the chain on the middle ring. If you see daylight between the chain and teeth of the ring, and the chain measures out ok, then the chainring is indeed worn.

  10. #10
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    I don't know about the brand you're using, but I can say that I wore out the middle ring of an XT chainring set in a LOT less than 8 months. That said, the XT rings are notoriously soft.

    Larry

  11. #11
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    If I do decide to replace the crankset, I was going to go with the XT cranks. I have also heard Raceface has some nice products as well. Any recommendations?

  12. #12
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    The pic is blurry but obvious enough, if the teeth are sharp and pointy it's time for a new set

    I bought myself a new LX crank (hollowtech)
    for me it was the best option, because replacing the rings was almost as expensive as buying a whole new crank + I wanted to experience the difference between octalink and the latest bottom-brackets from Shimano

    I read some bad stuff about the XT bearings, maybe they improved now, but I went LX.

    Replacing the chain before it's too late is the message I guess, because otherwise you trash the rings too.

    Check this out:
    http://miketechinfo.com/SRAM/chains2.htm#Chain%20wear

    Hope it helps

  13. #13
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    Quote Originally Posted by Steve030687
    If I do decide to replace the crankset, I was going to go with the XT cranks. I have also heard Raceface has some nice products as well. Any recommendations?
    I definitely like the XT cranks, but I prefer the Raceface Race (or Team) chainrings. In my experience (which others may or may not agree with) the Raceface rings shift just as good if not better than the XT rings, but they are much less susceptible to chainsuck, and they last longer.

    Larry

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