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  1. #1
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    Chain getting jammed up on big gear shifting

    Hi all,

    Due to budget, working with all alivio components (stock) for now. I have a problem when shifting from the front middle to front small gear while traveling up a slight incline. What happens is, every now and then, the chain will drop down to the smallest gear in front, but when the gear change is almost complete and the bottom of the middle gear finally loses contact with the chain, it somehow is bringing the chain back up (like it's grabbing the link that it touches last) and shoving it back underneath the front derailer and jamming it next to the top side of the chain. I'll actually have the top side of the chain resting tightly right next to the bottom side that was just brought back up.

    There doesn't appear to be any bends or jagged edges on the front cog rings or any abnormalities with the chain, so I'm pretty puzzled as to how it is happening. I go riding with my father in law, who is an avid rider for the past twenty or so years, who is also puzzled.

    Any help is greatly appreciated, thanks!

  2. #2
    Fat-tired Roadie
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    Chain suck.

    Bummer.

    Here's a graphic that looks more complicated than it is.



    The executive summary is that clean, well lubricated, new components rarely get chain suck, and dirty, worn out components get it pretty badly. Wear problems, here, would be with your chain or your middle ring.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  3. #3
    EDR
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    Quote Originally Posted by AndrwSwitch View Post
    Chain suck.

    Bummer.

    Here's a graphic that looks more complicated than it is.



    The executive summary is that clean, well lubricated, new components rarely get chain suck, and dirty, worn out components get it pretty badly. Wear problems, here, would be with your chain or your middle ring.
    that's the worst flow chart I've ever seen

  4. #4
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    looks like a lecture on why you should clean your bike frequently and properly

  5. #5
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    Your chain / drive train is worn. You have 2 choices

    New Chain and Chain rings (You have to replace both) Cassette might also need replacing

    or

    Use Lacquer thinner to completely clean the chain/drive train for each ride
    then re-lube for each ride. It's the chain lube gunk that is promoting the chain suck. It has to be thoroughly cleaned every ride

    I'm sure someone will follow this post and tell me I'm doing this wrong but
    I ride hundreds of miles on my xtr system with a 1/2 link stretch using this method (it's expensive to replace so I go as long as I can)
    I also Never ride in small ring

  6. #6
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    Thanks for all the replies, they were very informative.

    I've only been riding for a month now, and the bike has only been on 4 rides since brand new. After every ride I wash the bike thoroughly with degreaser and water, and scrub every chain ring and link with a toothbrush. Afterwards, once it's dry, I re-lube with Dynatek (I think it's called that, it's the expensive chain lube) on the chain and some all-purpose lube for everything else. The bike looks pretty much brand new before every ride.

    Could it be simply the Alivio components not holding up at the front? I'm not conditioned enough yet to take steep inclines without the small ring up front, so it's not an option to stick with the big and middle gears only.

  7. #7
    Fat-tired Roadie
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    Alivio chain rings did pretty well for me until I wore them out. Or maybe it was Acera - I can never remember which is which.

    I have a much less involved maintenance regime than either you or 3034, and don't get chainsuck unless it's crazy muddy. So I think there's something else going on.

    Can you replicate the problem off the bike? What about riding on flat ground?

    Shimano sometimes puts really tall teeth on the small ring. I haven't had a problem with them, but if your chain is already on the small ring when you get your chainsuck problem, that could be it.

    Shimano puts shift pins on the in-facing face of the middle chain ring to facilitate shifting up. I could imagine these causing a problem, especially during a shift, if your chain is too wide. What chain do you have? What crank, exactly, do you have, and how many cogs on your cassette?
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  8. #8
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    Quote Originally Posted by AndrwSwitch View Post
    Alivio chain rings did pretty well for me until I wore them out. Or maybe it was Acera - I can never remember which is which.

    I have a much less involved maintenance regime than either you or 3034, and don't get chainsuck unless it's crazy muddy. So I think there's something else going on.

    Can you replicate the problem off the bike? What about riding on flat ground?

    Shimano sometimes puts really tall teeth on the small ring. I haven't had a problem with them, but if your chain is already on the small ring when you get your chainsuck problem, that could be it.

    Shimano puts shift pins on the in-facing face of the middle chain ring to facilitate shifting up. I could imagine these causing a problem, especially during a shift, if your chain is too wide. What chain do you have? What crank, exactly, do you have, and how many cogs on your cassette?
    Off the bike or flat ground, I'm not able to replicate. Last weekend when it happened first, I re-lubed it up after wiping it clean (the chain) and did about 8-9 shifts on flat ground without a problem. I have a shimano chain (I'm sure it's the lowest model, came with the bike), and an alivio crank. The cassette has 9 cogs. The bike is the Fuji Outland 29er 3.0, if you want to look it up for any reason. Everything on it is stock (except for the seat, hah).

  9. #9
    Fat-tired Roadie
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    Make sure it's a 9-speed chain.

    According to Performance Bike, you have a Deore crank. And the chain is the HG-73, which is a 9-speed chain. Make sure there's not a stiff link somewhere. If the person who installed the chain did a bad job, the connection can be a little rough. Also, having too long a chain could contribute to the problem. The system basically relies on chain tension to get the chain to come off the crank.

    Park Tool Co. ParkTool Blog Chain Length Sizing
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  10. #10
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    Thanks for the link! I'll check it out this weekend and make sure the chain is the correct length. It makes perfect sense that as tension increases, it pulls the chain off the crank.

  11. #11
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    I checked the chain length when I came home, looks great. Hopefully I just didn't wash it well enough before the last ride, but I'll know for sure this weekend. I gave it a very thorough washing this evening, and there's no dirt whatsoever in the chain rings, cassette, or chain (or anywhere else for that matter). I re-lubed everything up and it looks brand new again, minus the normal wear and tear of riding a bike. If it still happens this weekend on the next ride, then I'll know it's not because of wear, dirt, or chain length.

  12. #12
    Rub it............
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    First off, stop degreasing your chain every ride. You just need to wipe down the outside of the chain with a little bit of spray degreaser like White Lightning Clean Streak and a rag. Then lube every 1-2 rides (dry lube) or every 2-4 rides (wet lube). Or right after the chain is completely dry after a very wet ride.

    Your chain suck is probably due to incorrect cleaning/lubing procedures. Too much cleaning can lead to degreaser/water still being inside the rollers, therefore not allowing the lube to penetrate properly.

    I degreased my chain (like you do) maybe twice last year. And that was due to riding in some decent mud. Other than that, I just wiped the chain with a dry rag and spray degreaser like the White Lightning Clean Streak, and lubed after every couple of rides. Never ran into chain suck during any of my rides. Including the 6 XC races that I did.

  13. #13
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    Quote Originally Posted by frdfandc View Post
    First off, stop degreasing your chain every ride. You just need to wipe down the outside of the chain with a little bit of spray degreaser like White Lightning Clean Streak and a rag. Then lube every 1-2 rides (dry lube) or every 2-4 rides (wet lube). Or right after the chain is completely dry after a very wet ride.

    Your chain suck is probably due to incorrect cleaning/lubing procedures. Too much cleaning can lead to degreaser/water still being inside the rollers, therefore not allowing the lube to penetrate properly.

    I degreased my chain (like you do) maybe twice last year. And that was due to riding in some decent mud. Other than that, I just wiped the chain with a dry rag and spray degreaser like the White Lightning Clean Streak, and lubed after every couple of rides. Never ran into chain suck during any of my rides. Including the 6 XC races that I did.
    +1!! I have an '08 Trek 6000 with 1,182 miles on it now (not a LOT but more than I thought I'd ever get on it), and never had a problem until I thought I was staying up on maintenance. Turns out, I was over-lubing my chain, over-cleaning, you name it. And it ended up gunking up with crud while I was riding really quick. I've learned that I really don't need to lube it unless it feels gritty or starts squeaking. And for me, that's about every 150 miles or so.

    My LBS guy told me that he's seen chains last 1000 miles that never saw a drop of lube, but chains that are degreased/lubed every ride have died in 200 miles. When you degrease, it apparently washes out almost all of the factory lube, and you have to lube the crap out of it to restore it to nearly as good as it was originally. Stop degreasing!!
    -Eric

  14. #14
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    Thanks for the information about cleaning, it's a complete opposite of what my LBS and friends have told me (but, totally makes sense). I've always been apprehensive about doing such thorough cleanings, but I figured, "Hey, they know more than me. I'm a newb at this." Good to know the real procedure though.

    So, dirt is not a bad thing in the chain I take it? Just wipe the outside down with a dry rag, use a little spray degreaser, and be done with it except for every 2-4 rides re-lubing with my wet lube. Sounds good, and much easier and less time consuming than what I've been doing.

    Goodbye, always-having-my-bike-look-brand-new. Hello, real mountain bike.

  15. #15
    Fat-tired Roadie
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    Of course dirt is bad. But you're riding a mountain bike on a trail made of dirt. Your chain gets dirty within minutes. It's more a matter of finding a balance between wasting your time maintaining your bike at an unsustainable level, that's far beyond what's useful, the life of your components, and the value of your time.

    IME, it takes a pretty long time, overnight or so, for a wet chain to dry. It's also hard to get degreaser to rinse out well. I think you may have found a very backwards way to run your chain unlubricated. At least, inside the rollers, where it really matters.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  16. #16
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    Got it, thanks. Just for good measure, I'll re-lube it a little today. I don't ride again until tomorrow afternoon.

  17. #17
    Rub it............
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    I am currently the lead mechanic for a LBS. Unless the customer requests a drivetrain cleaning - removal and soaking of all drivetrain parts - I just use the method I described above. And even in some instances, I let the customer know that a full soaking is not needed most times if just the occasional wipe down is performed.

  18. #18
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    I wipe my chain off and use an air compressor on the gears when everything gets a little grimy. It's fine to keep it looking new; you just don't want to degrease your chain very often. If ever. Just wipe it off with a rag and re-lube when it gets squeaky and sticky.

    I've now done mine twice in 200 miles; which I feel is a little too much now but it got squeaky on me a second time. I don't think I got enough lube in there the first time. I'm also using wax lube so it may take it a few applications to get worked in properly I suppose.

    Either way, the rule I've learned is that if you feel like you're doing a lot to take care of it, you're probably doing more damage than good. lol.

    -Eric

  19. #19
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    Thanks rccardude04, that's a good rule to go by. I always thought that the dirt that doesn't get removed from surface wiping would harm the chain, but I can see how washing it down every time would harm it more. I'll try the KISS method for the next few months and see how it goes.

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