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  1. #1
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    Chain jammed when front gear set shifts

    I tried to search for this issue everywhere, but I lack the proper knowledge to adequately describe the problem. I was on my second ride with my new Specialized Hardrock 29 Disc. We were working our way through the rear gears, then I decided I wanted to see how it was for the front gears to be shifted, the difference that made. I just know it was a usage error, but when i shifted from 2 to 1 on the left side, all of a sudden my pedaling ground to a halt.It took me a good 5 minutes to replace the chain on the first gear, so then first thing I did when the wheels went back down on the ground, was shift back up to 2nd. This time I wasn't going near as heavy, so instead of getting it stuck, it just came off and I was able to put it back on super easy. Since then I HAVE NOT TOUCHED the front shifter... Which is definately called something else.

    Here is a picture of the damage that chain caused when it got stuck. (I know bikes dont stay perfect, but it still hurt my soul to see this damage that I probably caused.)photo.jpg

  2. #2
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    sounds like your shifting mechanisms are not working properly. you might think about taking it to your local bike store and having it looked at or tuned up before something breaks.

  3. #3
    Andrew R Stewart Andrew R Stewart's Avatar
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    While out of adjustment shifters are not uncommon their ability to inflict damage is controled by the rider's inability to shift with care. Did the OP relax the pedalling pressure (soft pedal) during the front shifting? The front shifter is acting on the top side of the chain run, the side that is under tension when pedalling hard, or not. It's asking A LOT of a front shifter to push a highly tensioned chain sideways.

    Chain and chainring tooth damage from power shifting is VERY common. If the OP returns the bike to the LBS don't be surprised if they hem and haw about who's responsibile. Think of it like shifting a car's manual transmission without using the clutch. The photo shows classic chain suck stay scratching. This damage can also include damage that will hinder shifting after the incident.

    Now if the OP is a skilled rider and can present a case for proper shifting then the LBS will have to weight the situation differently then I suspect they will do. Given the discription by the OP I doubt this. Sorry to be blunt. Andy.

  4. #4
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    Quote Originally Posted by Andrew R Stewart View Post
    While out of adjustment shifters are not uncommon their ability to inflict damage is controled by the rider's inability to shift with care. Did the OP relax the pedalling pressure (soft pedal) during the front shifting? The front shifter is acting on the top side of the chain run, the side that is under tension when pedalling hard, or not. It's asking A LOT of a front shifter to push a highly tensioned chain sideways.

    Chain and chainring tooth damage from power shifting is VERY common. If the OP returns the bike to the LBS don't be surprised if they hem and haw about who's responsibile. Think of it like shifting a car's manual transmission without using the clutch. The photo shows classic chain suck stay scratching. This damage can also include damage that will hinder shifting after the incident.

    Now if the OP is a skilled rider and can present a case for proper shifting then the LBS will have to weight the situation differently then I suspect they will do. Given the discription by the OP I doubt this. Sorry to be blunt. Andy.
    I never said that I shifted properly. I even approached the question in such a way to be clear that I am more than aware that it was probably a beginner mistake. More than anything I was looking for information on what I did wrong, or more importantly, the right way to shift the front. The only thing the LBS guy said, was when shifting down, slow down and hold the shifter in. Andy, I definitely don't have a problem with you being blunt, and in fact prefer it, but I have no intention of blaming my own ineptness on anyone else.

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    The frame is fine, you can use model builder's enamel or nail laquer as an easy source of touch up paint. The "go slow" advice was a bit so-so, the important part is to ease off on the pressure on the pedals until the chain has settled in the new position. On sheldonbrown.com you can find a description on how to use the gears properly. And parktool.com has an excellent tutorial on how to make sure they're properly adjusted.
    Don't give until you know how to use ALL of your bike's new features. You're kinda selling yourself short if you can't use all the chainrings.

  6. #6
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    It's impossible to tell from your post if it was a misadjustment or something you did, but since the bike is new, you're entitled to some support from the dealer. Bring it in and ask them to check the bike, and review shift procedure with you so you can get best use out of out and enjoy it with confidence.

    Your fault or not, you don't want a repeat event, so some practice near the dealer is a good idea.

    As for the scratches, 2 minutes with some touch up paint will take care of that.
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  7. #7
    Andrew R Stewart Andrew R Stewart's Avatar
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    Quote Originally Posted by new2twowheels View Post
    I never said that I shifted properly. I even approached the question in such a way to be clear that I am more than aware that it was probably a beginner mistake. More than anything I was looking for information on what I did wrong, or more importantly, the right way to shift the front. The only thing the LBS guy said, was when shifting down, slow down and hold the shifter in. Andy, I definitely don't have a problem with you being blunt, and in fact prefer it, but I have no intention of blaming my own ineptness on anyone else.
    I think we're in agreement. Being a shop wrench and since I often reply with other readers in mind I took the stance I did.

    At work we offer a shifting clinic every month, it's my favorite to lead. Watching the customers' eyes open up as they realize what they've been doing "less then best" and why their shifting issues happen, then having them come back and thank us for teaching them how to get best performance during their riding "is priceless". The short version is to keep the pedals rotating but ease off the pressure while moving the shift lever just past the index click (for shifting up to a larger ring/cog, if shifting to a smaller one the lever will only move to the index click position w/ no over movement). Then reapply pressure after the chain is fully engaged. A key to this, and have little or no loss of momentum, is to time the shifting point WRT your location on the road/trail. Shift a bit early to stay on top of your ability to spin the pedals rapidly enough so there's a "fast chain running over the teeth" to allow the shift to happen quickly. Waiting until you bog down is too late for smooth and "flowing" shifting. This is but one reason that spinning instead of grinding is a good idea.

    Good luck with your repairs and future riding. Andy.

  8. #8
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    Quote Originally Posted by Andrew R Stewart View Post
    I think we're in agreement. Being a shop wrench and since I often reply with other readers in mind I took the stance I did.

    At work we offer a shifting clinic every month, it's my favorite to lead. Watching the customers' eyes open up as they realize what they've been doing "less then best" and why their shifting issues happen, then having them come back and thank us for teaching them how to get best performance during their riding "is priceless". The short version is to keep the pedals rotating but ease off the pressure while moving the shift lever just past the index click (for shifting up to a larger ring/cog, if shifting to a smaller one the lever will only move to the index click position w/ no over movement). Then reapply pressure after the chain is fully engaged. A key to this, and have little or no loss of momentum, is to time the shifting point WRT your location on the road/trail. Shift a bit early to stay on top of your ability to spin the pedals rapidly enough so there's a "fast chain running over the teeth" to allow the shift to happen quickly. Waiting until you bog down is too late for smooth and "flowing" shifting. This is but one reason that spinning instead of grinding is a good idea.

    Good luck with your repairs and future riding. Andy.
    Hey Andy!

    Thanks for the advice so much. Since I hate reading threads with no resolution (I sometimes literally ask my computer "Then what happened????!") I took your advice on shifting and spent my 6 mile neighborhood ride last night shifting every which way. Didn't miss or grind a single thing. It was too much pressure for sure those first couple times. My wife is waaay more experienced than me on a bike, and I think I shift more cleanly than her now! Between you and about 5 different youtube vids, everything is great now! Thank you so much for the advice.

  9. #9
    Andrew R Stewart Andrew R Stewart's Avatar
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    Quote Originally Posted by new2twowheels View Post
    Hey Andy!

    Thanks for the advice so much. Since I hate reading threads with no resolution (I sometimes literally ask my computer "Then what happened????!") I took your advice on shifting and spent my 6 mile neighborhood ride last night shifting every which way. Didn't miss or grind a single thing. It was too much pressure for sure those first couple times. My wife is waaay more experienced than me on a bike, and I think I shift more cleanly than her now! Between you and about 5 different youtube vids, everything is great now! Thank you so much for the advice.
    Another agreement, thread topics that are left unresolved. The follow up is how we learn. It's not just asking the question or reading every one's opinions to what is going on. But it's the conclusion to the problem that closes the loop.

    Thank you for taking the time to do this. Andy.

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