Can a steel frame flex enough to drop a chain?- Mtbr.com
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  1. #1
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    Can a steel frame flex enough to drop a chain?

    I've got a steel frame 29er singlespeed with sliding dropouts. I feel like I have a good idea of proper chain tension. Last year I raced this bike and during the race I had an issue with not enough chain tension and I started dropping the chain when putting in a hard acceleration. Not the hard effort of managing a climb with standing power, but flat terrain putting in an attack kind of effort. After happening twice in the race, I stopped and added more tension to the chain. Later in the race during a pass, the chain dropped again and I had a big wipe out and the bike went into a tree and destroyed the frame. This issue was probably initially my bad for not having proper chain tension at the start of the race, but I did stop to fix it and it still happened.

    Fast forward to last night. The frame had been replaced with an identical one. I have not had the issues again, although the night before I decided to go from a 21t to a 22t cog which is the same cog I used last year during the above-mentioned incident. I feel like I had good chain tension. During a fast attack on a bumpy uphill section which came after a downhill, the chain dropped. Luckily I did not have the same major wipe out like last year, but needless to say my confidence in this bike (which I LOVE) has just taken a big hit. Anyone have ideas on what I'm doing wrong here? Can a steel frame flex enough to drop the chain? It has only happened on bumpy, high rpm, high power efforts. Thanks.

  2. #2
    one chain loop
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    what is your chainring/cog/chain setup?
    everything sucks but my vacuum cleaner.

  3. #3
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    Are you running a single speed hub or geared hub with spacers? Maybe your chain line is off? I am no expert but i can't see your frame flexing enough to throw a chain, if this was common problem then titanium bikes would be in big trouble

  4. #4
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    setup is 34/22. Salsa aluminum chainring, surly cogs (22 and 21). chain is the wider SS-style (1/8"?). SS hub, chainline seems good although I have not done anything other than eyeball it. I have a hard time believing that a frame can flex that much, but I'm just brainstorming here. To be honest I think it is probably most related to maintaining my tension properly, but I feel like how much more attention can I be paying to this? I've already destroyed one frame and fork from not staying on top of it for painful lesson #1. Is this just lesson #2?
    Last edited by ewarnerusa; 06-11-2009 at 10:53 AM.

  5. #5
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    I'd get out the ruler and double check your chainline. I've never been able to eyeball chainline very well, personally.

    What do you weigh? What frame are you riding?

    At 200 lbs I can flex my 1x1's frame and that thing is a tank. When I first set up the SS I had the chain tension on the loose end of acceptable. Chainline was spot on, and I was using cogs with shift ramps at the time. It was fine riding around the street to test it out, but I found I would drop the chain when mashing uphill. I believe I was flexing the frame enough to cause the chain to drop. The shift ramped cog and chainring didn't help matters I'm sure. Anyway, I increased chain tension until the problem stopped. If your chainline is good, and you've got a SS cog and chainring, that's pretty much the only thing you can do.

    Also, did your chain tension seem lower than you initially set it when you put the chain back on? You could be moving the sliders...
    Stache 7 --- Rigid Surly 1x1 B+ --- Dirt Drop CrossCheck

  6. #6
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    I weigh 195 lbs. I'll get a ruler out and measure the chainline tonight. I won't mention the frame yet because I don't want to sound like I'm badmouthing it as the builders have been kind to me with my issues.

  7. #7
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    I run the exact the same chainring/cog/chain setup and have never had a problem. I am 6'2 190 lbs.

    When you tighten the chain are you making sure the wheel is centered in the stays? If you tighten the chain more on the right side than the left the cog is going to be off center and possibly skipping?

    You should take a picture of your chain setup from the back of the bike and post it.

    Quote Originally Posted by ewarnerusa
    setup is 34/22. Salsa aluminum chainring, surly cogs (22 and 21). chain is the wider SS-style (3/32"?). SS hub, chainline seems good although I have not done anything other than eyeball it. I have a hard time believing that a frame can flex that much, but I'm just brainstorming here. To be honest I think it is probably most related to maintaining my tension properly, but I feel like how much more attention can I be paying to this? I've already destroyed one frame and fork from not staying on top of it for painful lesson #1. Is this just lesson #2?

  8. #8
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    Quote Originally Posted by cbrock450
    I run the exact the same chainring/cog/chain setup and have never had a problem. I am 6'2 190 lbs.

    When you tighten the chain are you making sure the wheel is centered in the stays? If you tighten the chain more on the right side than the left the cog is going to be off center and possibly skipping?

    You should take a picture of your chain setup from the back of the bike and post it.
    I'm not sure I'm following. When I tighten the sliders down, I make sure that the leading edge of the tire is centered between the chainstays while the wheel is mounted (quick release clamped).

  9. #9
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    You obviosuly have the wheel centered in the stays so scratch that theory.

    Quote Originally Posted by ewarnerusa
    I'm not sure I'm following. When I tighten the sliders down, I make sure that the leading edge of the tire is centered between the chainstays while the wheel is mounted (quick release clamped).

  10. #10
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    Are you using a torque wrench on the sliders? Have you checked for chain stretch before and after these incidents?

    I would think it far more likely that your sliders are coming loose enough for the chain to slack up.... or you are using a super cheap SS chain and hammering hard enough to stretch it out of spec in one race (seen it happen). When you drop the chain and retension in a race, there is no way you are getting it tight enough to hold using a multi-tool.

    Loc-tite the slider bolts, torque them down to spec, mark the positions, or measure the distance. Write it down, ride, recheck.

    And no- your frame is not flexing enough to drop the chain.

  11. #11
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    Quote Originally Posted by cbrock450
    You obviosuly have the wheel centered in the stays so scratch that theory.
    A good theory, though, thanks for thinking about this with me. Again, I use my uncalibrated eyeballs for this alignment. I have in the past had some issues with the sliding dropouts staying in place. Everyone says "the set screws make it impossible for the sliders to move forward" and I concur, but I had issues with the non driveside sliding backwards under heavy braking. This has been pretty much remedied, but I don't think the sliding dropout is that great. When i put the chain back on last night after the chain dropped, the wheel still looked well centered between the chain stays.

  12. #12
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    Quote Originally Posted by forkboy
    Are you using a torque wrench on the sliders? Have you checked for chain stretch before and after these incidents?

    I would think it far more likely that your sliders are coming loose enough for the chain to slack up.... or you are using a super cheap SS chain and hammering hard enough to stretch it out of spec in one race (seen it happen). When you drop the chain and retension in a race, there is no way you are getting it tight enough to hold using a multi-tool.

    Loc-tite the slider bolts, torque them down to spec, mark the positions, or measure the distance. Write it down, ride, recheck.

    And no- your frame is not flexing enough to drop the chain.
    checked the chain with chain checker and <0.75% stretch. It is a cheap chain, though. I don't have a torque setting for the sliders, although I am using a torque wrench at 5 ft-lb (~7 Nm). See my above comments on the sliders.

    EDIT: I checked the chain last year after the incident and it was not stretched. But I replaced it anyway with the one on it now. A cheap BMX chain. It is not stretched.
    Last edited by ewarnerusa; 06-12-2009 at 03:05 PM.

  13. #13
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    it is possible that the frame is flexing, some actually do flex enough in the BB or chainstay. highly unlikely though i've only seen a few bad enough.

    the chainring could be very out of round (or bent!) even with a good chainline this can drop the chain. seems simple, but make sure the cranks are tightened right down. make sure there are no bent teeth on either ring or cog that might be ramping the chain. take the sliders off, clean the living crap out of both the slider and the frame with alcohol/degreaser (i even sand mine periodically) then re-tighten sliders.

    consider using a dog fang (jumpstop, etc) so if the chain does jump it might prevent crashing and/or knee smashing during a race...
    what would rainbow unicorn do?

  14. #14
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    Quote Originally Posted by ewarnerusa
    checked the chain with chain checker and <0.75% stretch. It is a cheap chain, though. I don't have a torque setting for the sliders, although I am using a torque wrench at 5 ft-lb (~7 Nm).
    5 ft/lb? That's for things like carbon and superlight stems.

    I'd go more like 15-25. There may be a torque max for that size of bolt - don't want to round out the hex.

    My WI ecc hub (not the same thing I know) would slip and tighten the chain at the manufacturer recommended setting of 25ft/lb. Upped it to 30 ft/lb and it hasn't moved a hair since.

  15. #15
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    Quote Originally Posted by forkboy
    5 ft/lb? That's for things like carbon and superlight stems.

    I'd go more like 15-25. There may be a torque max for that size of bolt - don't want to round out the hex.

    My WI ecc hub (not the same thing I know) would slip and tighten the chain at the manufacturer recommended setting of 25ft/lb. Upped it to 30 ft/lb and it hasn't moved a hair since.
    LOL, good to know. I have never used a torque wrench until this season. I fussed with things last night after I got home and tensioned the chain to the point where it is just about to make funny sounds but has smooth action. Chain seems pretty tight. I'll torque those bolts down at a higher setting. Last year I was given new sliders/bolts/washers because I mentioned to the builder how I was having issues with them slipping and showed him pictures and he said he could tell from the pics of worn aluminum washers that I was tightening them too much. So that is the reason I have been easy on them.

  16. #16
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    I have dropped the timing chain on our Specuialized Deja Tu tandem (made in the USA by American-aka Rodriquez), due to a super steep off camber 90* up hill grunt.
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  17. #17
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    Quote Originally Posted by ewarnerusa
    ...he said he could tell from the pics of worn aluminum washers that I was tightening them too much. So that is the reason I have been easy on them.
    I'd switch to steel washers as well. The deformation and wear of the aluminum washers could also allow slippage. Cost you a buck at the local hardware store.

    Poking around the interwebs, looks like average recommended torque for a 6mm hex is about 15ft/lb (20nm) and 5mm is 10 ft/lb.
    Last edited by forkboy; 06-11-2009 at 09:26 AM.

  18. #18
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    Quote Originally Posted by ferday
    it is possible that the frame is flexing,.
    Anything is possible, but I find it hard to believe that a steel hardtail is flexing more than a Moots YBB with 1 1/8" rear wheel travel. You can run those SS with sliders and not drop a chain.

  19. #19
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    Quote Originally Posted by forkboy
    I'd switch to steel washers as well. The deformation and wear of the aluminum washers could also allow slippage. Cost you a buck at the local hardware store.

    Poking around the interwebs, looks like average recommended torque for a 6mm hex is about 15ft/lb (20nm) and 5mm is 10 ft/lb.
    Thanks for the torque values. I think I will swap some aluminum for steel bits as well.

  20. #20
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    dog fang?

    Quote Originally Posted by ferday
    ...consider using a dog fang (jumpstop, etc) so if the chain does jump it might prevent crashing and/or knee smashing during a race...
    Is that a tensioner? The thought of adding a tensioner for added security has definitely crossed my mind.

  21. #21
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    Sounds like you have a Voodoo Dambala (or Wanga).
    I couldn't get those damned sliders to work no matter what I tried.
    The brake side slider would slip backwards.
    On the other hand, a friend of mine has a Voodoo Wanga and has never had a single issue with his sliders.

  22. #22
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    Quote Originally Posted by ewarnerusa
    Is that a tensioner? The thought of adding a tensioner for added security has definitely crossed my mind.
    looks like this. its just a precaution if the chain is dropping at the ring

  23. #23
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    I'd definitely say it is _possible_... not likely, however. I dropped a chain on a climb recently on my old Monocog (a 4130 frame) that I'm pretty much going to attribute to flex around the bottom bracket. The climb was steep and technical, and I'm running a 32-22 on that bike which puts down alot of torque. 1/8" Chain on single-speed rings.

    Fortunately, the chain came free with my foot pretty close to the bottom of the pedal stroke so no missing teeth. Sort of irritating though.

  24. #24
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    Quote Originally Posted by Thor29
    Sounds like you have a Voodoo Dambala (or Wanga).
    I couldn't get those damned sliders to work no matter what I tried.
    The brake side slider would slip backwards.
    On the other hand, a friend of mine has a Voodoo Wanga and has never had a single issue with his sliders.
    Good to hear that I'm not the only one! When I discuss it with people they typically start right in with "the set screw won't allow it to move" explanation. When i say that forward slippage isn't the issue, they reply "put a nut and washer on the set screw, then it can't loosen up."

  25. #25
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    Hmm... never had that issue on my Monocog 29er and I run about 215-220. I'd suspect chainline or chainring out of round like suggested earlier. That may cause greatly uneven chain tension.

    When you tension the chain, do you have tight spots in the crank rotation? And are you adjusting for slack at the tight spots? How much play is present in the tight spots?

    Conversely, what is the play like in the loose spots in the rotation?

    Whenever I had dropped a chain on my SS it was on descents, but it did happen under power... of course my biggest race of the year. The culprit was a chainring that was not the Surly that I'd been running all year. It wasn't as round, and the teeth were smaller. Smaller margin for error. The Surly's have really tall teeth that let you get away with slightly sloppy chain tension and not lose the chain.

  26. #26
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    Quote Originally Posted by sunset1123
    I'd definitely say it is _possible_... not likely, however. I dropped a chain on a climb recently on my old Monocog (a 4130 frame) that I'm pretty much going to attribute to flex around the bottom bracket. The climb was steep and technical, and I'm running a 32-22 on that bike which puts down alot of torque. 1/8" Chain on single-speed rings.

    Fortunately, the chain came free with my foot pretty close to the bottom of the pedal stroke so no missing teeth. Sort of irritating though.
    Mine has only dropped during high rpm/high power stuff. In last year's incident after I retensioned the chain, the course points upwards and I stood and mashed that climb with no issues. Then on a later flat section I was making a pass (high rpm/high power) when the chain dropped and I biffed it. When it dropped on me last night it was similar to how you described with no wipe out or missing teeth, but very irritating.
    Last edited by ewarnerusa; 06-11-2009 at 10:57 AM.

  27. #27
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    Quote Originally Posted by racerdave
    Hmm... never had that issue on my Monocog 29er and I run about 215-220. I'd suspect chainline or chainring out of round like suggested earlier. That may cause greatly uneven chain tension.

    When you tension the chain, do you have tight spots in the crank rotation? And are you adjusting for slack at the tight spots? How much play is present in the tight spots?

    Conversely, what is the play like in the loose spots in the rotation?

    Whenever I had dropped a chain on my SS it was on descents, but it did happen under power... of course my biggest race of the year. The culprit was a chainring that was not the Surly that I'd been running all year. It wasn't as round, and the teeth were smaller. Smaller margin for error. The Surly's have really tall teeth that let you get away with slightly sloppy chain tension and not lose the chain.
    A SS rider/shop wrench was with us last night and went over some of what you are mentioning when he looked at it. It was new knowledge for me. He thought that things seemed consistent with the tension, but this was trailside with the rest of the group giving us the "let's get going" vibe! Do you think the Salsa aluminum chainring with a season of wear could be suspect?

  28. #28
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    You can drop a chain due to frame flex.
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  29. #29
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    Hmm... I don't think a season of wear would do it. But I could be wrong, depending on conditions, etc. Dropping it on the decent seems like a tension thing to me, not flex. I'd try getting the slop out of it to the point it binds up a bit, then loosen it a just tad and ensure you get no more binding. Don't want it too tight, but it sounds as though it might be a bit loose. If not, I'm as perplexed as you are.

  30. #30
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    Quote Originally Posted by racerdave
    Hmm... I don't think a season of wear would do it. But I could be wrong, depending on conditions, etc. Dropping it on the decent seems like a tension thing to me, not flex. I'd try getting the slop out of it to the point it binds up a bit, then loosen it a just tad and ensure you get no more binding. Don't want it too tight, but it sounds as though it might be a bit loose. If not, I'm as perplexed as you are.
    It dropped on my savage attack on the uphill following the decent. I basically retensioned last night at home like you describe and I'll add some torque to the slider bolts before riding it again.

    Thanks everyone for the input

  31. #31
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    Chain tension is fairly even... about as good as it gets without some kind of tensioning device. Chainline is within 0.5mm. I'm really starting to think about running a bottom bracket style tensioner and/or fab up some guide rings.

    So far, just the one time ripping up a steep rocky climb... I was turned and off-camber at the time also.

    I've noticed more flex in this frame as time goes on, which leads me to believe it may be time for a new frame... pity, I REALLY like the geometry of this one.

  32. #32
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    I have the zaka and i have never had problems


    Quote Originally Posted by Thor29
    Sounds like you have a Voodoo Dambala (or Wanga).
    I couldn't get those damned sliders to work no matter what I tried.
    The brake side slider would slip backwards.
    On the other hand, a friend of mine has a Voodoo Wanga and has never had a single issue with his sliders.

  33. #33
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    Quote Originally Posted by forkboy
    I'd switch to steel washers as well. The deformation and wear of the aluminum washers could also allow slippage. Cost you a buck at the local hardware store.

    Poking around the interwebs, looks like average recommended torque for a 6mm hex is about 15ft/lb (20nm) and 5mm is 10 ft/lb.
    Yikes, the sliders did not like 10 lb-ft of torque. The aluminum outer washers just started to deform. non-drive side was fine, drive side started to deform. I had another set of Al washer that I put on. I sent an email to the builder asking about a steel alternative.

    These aren't washers as in the round ones under a bolt head that you buy at a hardware store. They are a single piece that both slider bolts go through. I call them washers because the builder called them that when corresponding with me. I'm not sure of a better term. The one on the left is new, the others are what they end up looking like when I get ahold of them.

  34. #34
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    Quote Originally Posted by ewarnerusa
    The one on the left is new, the others are what they end up looking like when I get ahold of them.[/IMG]
    Yikes is right! If it's wearing away that quickly, no wonder it's not holding.

    Could you just put some normal steel washers inbetween the bolt heads and the aluminum slider thing?

  35. #35
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    Quote Originally Posted by forkboy
    Yikes is right! If it's wearing away that quickly, no wonder it's not holding.

    Could you just put some normal steel washers inbetween the bolt heads and the aluminum slider thing?
    that ran through my head last night and I think that's a good idea.

    EDIT: builder got back to me and said they'll send out a new steel version of the washers right away. Woohoo! He also said check the chainline!! As well as chain ring bolts.
    Last edited by ewarnerusa; 06-12-2009 at 03:04 PM.

  36. #36
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    Quote Originally Posted by Velobike
    You can drop a chain due to frame flex.
    Your reply has been the only definitive "yes you can". Can you elaborate?

  37. #37
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    Quote Originally Posted by ewarnerusa
    Your reply has been the only definitive "yes you can". Can you elaborate?
    Depends on the frame.

    I get this problem mainly on old steel frames converted to SS. Generally they have been designed for use with a derailleur so flexibility of the chainstays is a design feature for comfort. Stomping on the pedals seems to do the trick - maybe a smoother cycling motion wouldn't cause a derailment. The chainline can vary quite markedly. Frames designed for single speed or track use are much less prone to this problem.

    My theory is that the lateral movement of the chainstays, is not in itself sufficient to do the job, but when compounded by rapid alterations in the bending direction in the lateral plane, sort of like a whipping motion, then throws off the chain. Bend in the chainstay means the rear cog will be at an angle to the chain and this angle will be rapidly changing back and fore.

    My beltdrive conversion bikes are much more sensitive to this.

    Edit: has the original poster considered that his problem may be because he is much stronger now than last season - been known to happen
    Last edited by Velobike; 06-13-2009 at 02:14 AM.
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  38. #38
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    just thought I'd throw in the possibility of loose rear wheel bearings (although I'm sure you'd have checked this by now) as a cause for chain throwing.

  39. #39
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    One more thought: get a different chain, one that has more side flex. On my old steel frame (Inbred) I started with a SS specific chain (such as PC-1) and dropped it several times during hard efforts on rough terrain. I then switched to 8 speed chains (such as PC 870) and the problem went away.

    In other words, if you have a flexy frame, then a flexy chain might be better.
    My rides:
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  40. #40
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    Horrible thought - if it is a steel Voodoo - check the inside of the chainstay near the BB. Is there a crack? I know of one Wanga that had a small crack that grew until it was enormous. Voodoo replaced the frame no problem.
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  41. #41
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    Quote Originally Posted by Velobike
    Horrible thought - if it is a steel Voodoo - check the inside of the chainstay near the BB. Is there a crack? I know of one Wanga that had a small crack that grew until it was enormous. Voodoo replaced the frame no problem.
    I didn't find any cracks thankfully! I just measured the chainline via Fishcreek method and it was off by about 5 mm. I flipped the Surly cog around and that brought it right in line. Also, the chainring bolts were mostly tight, but I did get an eighth to a quarter turn tighter on some of them. Gotta stay on top of this stuff!!

    I recently tightened down the rear hub bearings, so I don't think that is the culprit.

  42. #42
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    I dropped a chain a couple weeks ago for the first time in....ever.

    KM, Forged WI cranks (old 94 bcd's) with a Surly ring, WI freewheel, Tuggnut, some chain, Shimano HG I think.

    (I worked at a shop that had a bunch of IG chains, which don't work on anything except InterGlide crap, but they are excellent SS chains; very strong and beveled on the outside of the plates rather than the inside reducing the tendency to throw itself, so I stocked up.)

    I had left the chain just a bit slack from taking out the rear wheel for something, and about halfway through a ride on a short and shallow climb, my chain dropped. It sounded and felt like a stick or some other debris got caught up and when it wound through, the chain popped off.

    No damage to the frame, chain, chain ring or freewheel.

    I suspect there was just enough slack in the chain and just enough give in the stays that it allowed to chain to come off.

    What doesn't bend will break, that's (part of) why I prefer steel over aluminum.
    Last edited by j e SS e; 06-13-2009 at 02:20 PM.
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  43. #43
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    I have a KM and I used to drop my chain about once a ride on those little dips that turn into a turn and technical uphill. I switched out my back cog to something new with longer teeth, double checked my chainring and chain (both were fine). I haven't dropped it since.

    I didn't see this mentioned, so I thought I would. I have three SS or fixed bikes and I started spending one afternoon a month getting chain tension as perfect as I can and it really makes a difference on the ride. Good luck.

  44. #44
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    Chainline off by 5 mm sounds like the culprit.

    Any more news on how it behaved after the chainline correction?

  45. #45
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    just some things to consider for anyone having this problem, i've had brand a new factory built wheel dished quite a bit off, so if you centered the rim/tire in the frame, the hub is crooked. Also, if you're using a master link, they go bad pretty often for me, causing me to drop my chain. The worst are the sram golden links, but i've mangled a few 1/8" bmx style ones as well. They often dont look too bad, but looking at them closely shows evidence of bent pins, stretched side plates, ect., and changing them has always fixed the problem.

  46. #46
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    Quote Originally Posted by racerdave
    Chainline off by 5 mm sounds like the culprit.

    Any more news on how it behaved after the chainline correction?
    I've got it all ready to rock, but then I've been riding my geared bike to get ready for a couple weekend races in a row. I only race the SS in a few races a year (mainly the ones with a SS category!) Normally I get the SS out at least on my Wednesday night group ride, but I'm sticking with the geared bike because of the races coming up. The new steel slider washers have not arrived yet, though.

    I'll look into the pins on the cheap BMX-style masterlink as well.

  47. #47
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    I would strongly suggest a 3/32 geared chain. It will actually fit the teeth without lateral play, and they are for the most part better chains overall than most any 1/8" SS chain.

    And a geared chain has no problem with an imperfect chain line since they are made to flex laterally.

    Aluminum chain rings are always suspect as well. Compare it with a fresh one to determine any wear; it's hard to just look at it and tell.

    If you can afford it, I'd get a new ring and new chain. I can almost guarantee that will solve your problem. Those cogs won't wear appreciably in your lifetime, so no worries there. I like Surly (or any steel) rings myself for the exact reason that alu rings are prone to such fast wear.

    I've been using all steel drive trains and geared chains for ~4 years and never had a problem with any of 5 or 6 bikes. With the one exception I noted above, but that was a tension issue.
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  48. #48
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    Quote Originally Posted by j e SS e
    I would strongly suggest a 3/32 geared chain. It will actually fit the teeth without lateral play, and they are for the most part better chains overall than most any 1/8" SS chain.

    And a geared chain has no problem with an imperfect chain line since they are made to flex laterally.

    Aluminum chain rings are always suspect as well. Compare it with a fresh one to determine any wear; it's hard to just look at it and tell.

    If you can afford it, I'd get a new ring and new chain. I can almost guarantee that will solve your problem. Those cogs won't wear appreciably in your lifetime, so no worries there. I like Surly (or any steel) rings myself for the exact reason that alu rings are prone to such fast wear.

    I've been using all steel drive trains and geared chains for ~4 years and never had a problem with any of 5 or 6 bikes. With the one exception I noted above, but that was a tension issue.
    I've been reading some other threads about 3/32" chains being better performers and I'll think I'll take your advice for the next chain. Same with a steel chainring.

  49. #49
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    Quote Originally Posted by ISuckAtRiding
    Also, if you're using a master link, they go bad pretty often for me, causing me to drop my chain. The worst are the sram golden links, but i've mangled a few 1/8" bmx style ones as well. They often dont look too bad, but looking at them closely shows evidence of bent pins, stretched side plates, ect., and changing them has always fixed the problem.
    Good point about this. I had similar issues and have since gone "masterlink-less" since and no repeats of that being the weak point when it comes to throwing the chain.

  50. #50
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    Quote Originally Posted by j e SS e
    I would strongly suggest a 3/32 geared chain. It will actually fit the teeth without lateral play, and they are for the most part better chains overall than most any 1/8" SS chain.

    And a geared chain has no problem with an imperfect chain line since they are made to flex laterally.

    Aluminum chain rings are always suspect as well. Compare it with a fresh one to determine any wear; it's hard to just look at it and tell.

    If you can afford it, I'd get a new ring and new chain. I can almost guarantee that will solve your problem. Those cogs won't wear appreciably in your lifetime, so no worries there. I like Surly (or any steel) rings myself for the exact reason that alu rings are prone to such fast wear.

    I've been using all steel drive trains and geared chains for ~4 years and never had a problem with any of 5 or 6 bikes. With the one exception I noted above, but that was a tension issue.
    I've had REALLY bad luck with the Surly stainless steel chain rings. The grade of stainless they use is wayyyy too soft, and it bends like butter. I think it took me a few months to make it unrideable. There is alot of loose rock around here, and when you're flying down the trail, they tend to fly at that lower portion of your bike, and it tweaks it just a hair. Next time you pedal, it either dumps your chain, and/or bends a tooth or 2 90 degrees over. This has happened to me on many occasions, and has cost me a race as well. The final straw was when i was climbing a hill and the chainring completely tacoed between 2 of the chainring bolts. I still have it somewhere in the garage if anyone wants pics.
    I've had zero problems with my e-thirteen aluminum downhill ring so far, it's considerably stiffer.

  51. #51
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    Quote Originally Posted by ISuckAtRiding
    I've had REALLY bad luck with the Surly stainless steel chain rings. The grade of stainless they use is wayyyy too soft, and it bends like butter. I still have it somewhere in the garage if anyone wants pics.
    we love pictures.
    everything sucks but my vacuum cleaner.

  52. #52
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    Quote Originally Posted by fishcreek
    we love pictures.
    mind you i spend quite a bit of time trying to hammer it straight with a rock to get myself out of the woods. It was bent completely over to one side.


  53. #53
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    Of course I read this right after I just ordered a new Surly chainring.

  54. #54
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    Quote Originally Posted by ISuckAtRiding
    I've had REALLY bad luck with the Surly stainless steel chain rings. The grade of stainless they use is wayyyy too soft, and it bends like butter. I think it took me a few months to make it unrideable. There is alot of loose rock around here, and when you're flying down the trail, they tend to fly at that lower portion of your bike, and it tweaks it just a hair. Next time you pedal, it either dumps your chain, and/or bends a tooth or 2 90 degrees over. This has happened to me on many occasions, and has cost me a race as well. The final straw was when i was climbing a hill and the chainring completely tacoed between 2 of the chainring bolts. I still have it somewhere in the garage if anyone wants pics.
    I've had zero problems with my e-thirteen aluminum downhill ring so far, it's considerably stiffer.
    I had one get bent when another bike fell on mine, I straightened in a vice and still ride it.

    I'm lucky to have a 94 bcd crankset ; it gives my 32t considerably more support than a 104. I probably wouldn't want to run one on a 104, but steel wins out for longevity, hands-down.

    One could always run a bashguard (good use for a salsa ring, actually)....but then you have a bashguard on your bike. May as well be a nipple on your forehead.
    Last edited by j e SS e; 06-17-2009 at 12:15 PM.
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  55. #55
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    I'm hoping my setup will be strong with a 110 BCD 5-arm crank and 34t chainring. The Al one has certainly held up just fine.

  56. #56
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    Quote Originally Posted by ewarnerusa
    I'm hoping my setup will be strong with a 110 BCD 5-arm crank and 34t chainring. The Al one has certainly held up just fine.
    5 bolt should be ok as far as not folding in half. I had a 104 4 bolt, and as Jesse said, it's just too flimsy. My guess is that it's made out of 303 or 304 grade, which is butter soft. Idealy it should be made out of heat treated 17-4, but that would cost a bit more to make.

    I havent had any issues with aluminum ones either, but 7075-t6 aluminum (chainring material) has a higher yeild strength than most stainless steels, meaning that it takes alot more to bend.

    As far as longevity, the stainless is only better as far as wear goes, but i'd much rather change my ring more frequently than be stuck in the woods with a 90 degree chainring again lol

  57. #57
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    Quote Originally Posted by ISuckAtRiding
    5 bolt should be ok as far as not folding in half. I had a 104 4 bolt, and as Jesse said, it's just too flimsy. My guess is that it's made out of 303 or 304 grade, which is butter soft. Idealy it should be made out of heat treated 17-4, but that would cost a bit more to make.

    I havent had any issues with aluminum ones either, but 7075-t6 aluminum (chainring material) has a higher yeild strength than most stainless steels, meaning that it takes alot more to bend.

    As far as longevity, the stainless is only better as far as wear goes, but i'd much rather change my ring more frequently than be stuck in the woods with a 90 degree chainring again lol
    304 according to their website. It never meant anything to me before, so thanks for the technical info.

  58. #58
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    i rode behind a fellow on a pretty high end steel SS today. I was amazed how much the chain slackened on every rotation of his crank. Deffinately possible for it to drop in some circumstances IMO.

  59. #59
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    Can a steel frame flex enough to drop a chain?
    yes....i just did it an hour ago....threw all my soft bits into/onto my bike and somehow got a chainring burn on my left calf for chrisakes!......my friend thought it entertaining......fugger....

    chain tension is fine...chainring is fine (ENO)....WI Trials freewheel is fine.....chain is fine......1X1 frame is noodley though......BLARGH!
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  60. #60
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    Quote Originally Posted by CHUM
    yes....i just did it an hour ago....threw all my soft bits into/onto my bike and somehow got a chainring burn on my left calf for chrisakes!......my friend thought it entertaining......fugger....

    chain tension is fine...chainring is fine (ENO)....WI Trials freewheel is fine.....chain is fine......1X1 frame is noodley though......BLARGH!
    OUCH!!
    My setup has not dropped the chain lately, but I have been paying quite a bit more attention to the geared bike lately with my race goal of the season coming up. In the meantime, though, I've switched to a steel Surly chainring, aligned the chain a bit better (flipped rear Surly cog around), and I was supplied some stainless steel washers from the bike builder to replace the deformed aluminum ones. I bought new screws from the hardware store and I can tell that the new bits take the torque much better when tightening things down. The slippage issue that I always seem to fiddle with whenever I make a slider adjustment seems to not have happened at all this time around.

  61. #61
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    I have also had problems with the surly 304 stainless chainring. Therefore I made myself a chainring out of 4435 stainless steel witch is a lot better. The surly chainring is 2.2mm as far as I remember. I made mine out of 3.3mm plate. It runs very smooth and it is very noticeable that it is more rigid than the surly. On climbs my guess is that I gain up to 10%. I will post some pics later...

  62. #62
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    Some photos

    Quote Originally Posted by jakerollo
    I have also had problems with the surly 304 stainless chainring. Therefore I made myself a chainring out of 4435 stainless steel witch is a lot better. The surly chainring is 2.2mm as far as I remember. I made mine out of 3.3mm plate. It runs very smooth and it is very noticeable that it is more rigid than the surly. On climbs my guess is that I gain up to 10%. I will post some pics later...




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