Chain falls off need help and suggestions- Mtbr.com
Results 1 to 33 of 33
  1. #1
    mtbr member
    Reputation:
    Join Date
    Dec 2011
    Posts
    14

    Chain falls off need help and suggestions

    I am riding in Florida. Its flat but with a lot of roots. I started with a rockhopper. The chain consistently fell off. After about ten visits to the shop and lots of bruises and contusions from the sudden and unexpected chain loss, it was decided the frame was flexing. I am told I am a masher. Enter the new stumpjumper frame.

    I have ridden it twice. The first time I had no problems. The second time, I got more aggressive. The chain fell off. But, it fell off going over a double root. I do not even think I pedaled, at least not hard.

    The bike has an ebb. I am running a race face evolve with 32 teeth and a 18t cog in the back. What can I do? The shop suggests some type of chain guard for the rear cog. Any suggestions or ideas?

  2. #2
    One Gear
    Reputation: .40AET's Avatar
    Join Date
    Jun 2007
    Posts
    1,070
    Check to make sure that the rear cog and the chain ring are both SS specific. The teeth are taller and will hold the chain better. I've run my chain pretty loose and it hasn't fallen off in the junk.

    Good luck

  3. #3
    mtbr member
    Reputation: SlowPokePete's Avatar
    Join Date
    Mar 2006
    Posts
    1,586
    Chain line?

    SPP
    Rigid.

  4. #4
    AZ
    AZ is offline
    banned
    Reputation: AZ's Avatar
    Join Date
    Apr 2009
    Posts
    19,198
    Pics of the chain line and of the chain ring and cog please.

  5. #5
    gran jefe
    Reputation:
    Join Date
    Nov 2011
    Posts
    2,692
    Quote Originally Posted by Ponsoldt View Post
    I am told I am a masher.
    Umm, it's a singlespeed? Isn't your choice either to mash, or get off and push?

  6. #6
    mtbr member
    Reputation:
    Join Date
    Dec 2011
    Posts
    14
    Quote Originally Posted by Bill in Houston View Post
    Umm, it's a singlespeed? Isn't your choice either to mash, or get off and push?
    I think so...but my chain falls off so what do I know.

  7. #7
    mtbr member
    Reputation:
    Join Date
    Dec 2011
    Posts
    14
    Quote Originally Posted by .40AET View Post
    Check to make sure that the rear cog and the chain ring are both SS specific. The teeth are taller and will hold the chain better. I've run my chain pretty loose and it hasn't fallen off in the junk.

    Good luck
    What are you running?

  8. #8
    mtbr member
    Reputation:
    Join Date
    Jun 2006
    Posts
    1,103
    I have no problems with Blackspire, Race Face, Salsa singlespeed specific chain rings and Surly cogs.

    if chain tension is not the issue, then your problem could be the chain line.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    714
    chainline or cog. I did have a jankety Novara frame that I converted to SS a few years ago and that thing would throw the chain like clockwork, seemingly regardless of what cog I was using or how straight the chainline was. It was super flexy in the rear triangle.

  10. #10
    gran jefe
    Reputation:
    Join Date
    Nov 2011
    Posts
    2,692
    Quote Originally Posted by Ponsoldt View Post
    I think so...but my chain falls off so what do I know.
    Ya, really. I guess if you didn't ride hard it would be fine...

    Lots of singlespeeders have some kind of little tensioner thingy. They all look pretty simple. Or they do the bashwich, which i kind of like for aesthetics.

  11. #11
    mtbr member
    Reputation:
    Join Date
    Jun 2006
    Posts
    1,103
    Quote Originally Posted by OneBadWagon View Post
    chainline or cog. I did have a jankety Novara frame that I converted to SS a few years ago and that thing would throw the chain like clockwork, seemingly regardless of what cog I was using or how straight the chainline was. It was super flexy in the rear triangle.
    Yeah, I had a steel SS several years ago that was very flexy and I had problems with that one. in this case, I can't imagine that the aluminum stumpjumper is an overly flexy frame.

    It has to be a pretty simple issue like ring/cog, chainline or chain tension. Is the EBB loosening in your ride? That will make the chain tension too loose and you will drop your chain as a result. I had a problem with that on one of my aluminum SS frames. The EBB sucked and would loosen up to the point of chain slap at times. That was a tough bike to ride... I got rid of that one pretty quickly.

  12. #12
    AZ
    AZ is offline
    banned
    Reputation: AZ's Avatar
    Join Date
    Apr 2009
    Posts
    19,198
    You need the proper chain ring and cog. Beyond that, if you chain line is not correct the chain is likely to fall off no matter what equipment you are running. What are you using and what does the chain line look like? Pics would help a bunch.

  13. #13
    mtbr member
    Reputation: jetboy23's Avatar
    Join Date
    Jun 2011
    Posts
    1,232
    I'm currently running an e.13 guidering and a niner cogolicious and never throw a chain. I even run a bit lose because my rear hub has some tight and loose spots. I can't imagine how much my frame would need to flex to throw a chain. More than half an inch? Thats not even a hard tail at that point.

  14. #14
    Fat & Single
    Reputation: ozzybmx's Avatar
    Join Date
    Jun 2008
    Posts
    4,109
    Masher, spinner or running a cadence computer on your SS ?

    Makes no difference mate, you should not be dropping a chain on a SS, ive had chain slap many of times and still never dropped one. Im not even running SS specific chainrings or cogs, you got a chainline problem or something else is going on there.
    Santa Cruz Hightower LT Evil Following Trek 9.9 Superfly SL IndyFab Deluxe 29 Pivot Vault CX Cervelo R3 Disc

  15. #15
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    714
    Quote Originally Posted by jetboy23 View Post
    I'm currently running an e.13 guidering and a niner cogolicious and never throw a chain. I even run a bit lose because my rear hub has some tight and loose spots. I can't imagine how much my frame would need to flex to throw a chain. More than half an inch? Thats not even a hard tail at that point.
    The twist in the rear end of that frame was absurd. With very little effort, putting pressure on the pedal sideways with the crank at 6 o'clock, the tire would rub. It was a failed beater experiment that ended up with a 1x8 and worked okay.

  16. #16
    mtbr member
    Reputation:
    Join Date
    Jun 2006
    Posts
    7,816
    It's either your chain line, chain tension, or a non-single speed cog.

  17. #17
    mtbr member
    Reputation:
    Join Date
    Oct 2008
    Posts
    1,166
    Do you have tight and loose spots in your chain when you pedal it backwards? If so, the problem could be that your front chainring is moving slightly as you pedal. I had this problem a few months ago, and it took me a while to figure it out, but it turns out my front chainring was moving slightly. If I adjusted the chainring, then all would be fine for a couple of rides, then the chain would get loose and pop off.

    Eventually, I switched to a blackspire ring and installed new chainring bolts. I followed guide on Sheldon Brown site to tension the chain, and the problem is gone.

  18. #18
    Ride,Smile, Pedal Damn it
    Reputation: henrymiller1's Avatar
    Join Date
    Apr 2008
    Posts
    552
    If your chainline is straight. Check your chain. I put a new $$ chain on my old SS and started dropping the chain over and over again. I put back on old chain and problem went away. Old chain was the cheap $20 sram. Good luck.

  19. #19
    mtbr member
    Reputation:
    Join Date
    Dec 2011
    Posts
    14
    Quote Originally Posted by wjphillips View Post
    Do you have tight and loose spots in your chain when you pedal it backwards? If so, the problem could be that your front chainring is moving slightly as you pedal. I had this problem a few months ago, and it took me a while to figure it out, but it turns out my front chainring was moving slightly. If I adjusted the chainring, then all would be fine for a couple of rides, then the chain would get loose and pop off.

    Eventually, I switched to a blackspire ring and installed new chainring bolts. I followed guide on Sheldon Brown site to tension the chain, and the problem is gone.
    Did the chain come off he back with this problem?

  20. #20
    One Gear
    Reputation: .40AET's Avatar
    Join Date
    Jun 2007
    Posts
    1,070
    Quote Originally Posted by Ponsoldt View Post
    What are you running?
    Surly chainring and cog. I used to have a cheap Truavit front ring that came with the crank and it worked well too.

    Surly cog
    Surly Chainring

  21. #21
    mtbr member
    Reputation:
    Join Date
    Oct 2008
    Posts
    1,166
    Quote Originally Posted by Ponsoldt View Post
    Did the chain come off he back with this problem?
    Yes, usually it was the back. Sometimes it would come off the front chain ring too.

  22. #22
    mtbr member
    Reputation:
    Join Date
    Jan 2012
    Posts
    4,317
    Post some photos of the chainline and setup from different angles. Some of us lazy guys run fairly lose chains and don't drop them. It doesn't seem like the frame should flex that much, how heavy are you?

  23. #23
    clown question, bro
    Reputation: zeppy's Avatar
    Join Date
    May 2011
    Posts
    499
    I'm thinking I have roughly the same frame you do ('10 Rockhopper SS specific with the EBB) and I haven't had any problems with losing the chain even though I'm a masher too (at 230lbs of mash-i-ness even).

    I would think it has to be your chainline. The only time I've had issues with the chain is when I first picked it up and the chain started to stretch a little.
    Quote Originally Posted by Ilikebmx999 View Post
    Are we just ignoring balls? Lol

  24. #24
    mtbr member
    Reputation:
    Join Date
    Dec 2011
    Posts
    14
    The chain comes off the back. Typically when I get a mechanic to go through it it works for a ride. I then start experiencing a creek from the back and the chain comes off. It never gets loose so it's not the bb. I am using skewers.

  25. #25
    mtbr member
    Reputation: SlowPokePete's Avatar
    Join Date
    Mar 2006
    Posts
    1,586
    Quote Originally Posted by Ponsoldt View Post
    The chain comes off the back. Typically when I get a mechanic to go through it it works for a ride. I then start experiencing a creek from the back and the chain comes off. It never gets loose so it's not the bb. I am using skewers.
    What specifically does the mechanic do? Adjust chain tension? Some kind of hub adjustment? Are your skewers somehow loosening (brand?)?

    The answer might lead to the solution ...

    SPP
    Rigid.

  26. #26
    mtbr member
    Reputation:
    Join Date
    Jun 2006
    Posts
    7,816
    Check your chainline. Usually I just stand behind the bike, look down the length of the chain, and make sure it's sitting straight. If it's off, then you'll see an angle in the chain right where it hits the chain ring, and again where it hits the cog.

    Good info:
    All About Bicycle Chainline

  27. #27
    Robtre
    Reputation: robtre's Avatar
    Join Date
    Apr 2008
    Posts
    706
    I jumped my chain for the first time yesterday. We rode a trail that had significantly longer steeper climbs then our routine trails. I have never in my 5 years of singlespeeding dropped a chain. I got it back on easily but noticed it was significantly stretched and was much slacker than before the ride. I checked the chain slack and greased the chain before my ride. Not sure what to do with the chain now, if I should replace it.

  28. #28
    mtbr member
    Reputation:
    Join Date
    Dec 2011
    Posts
    14
    No slack in chain and the chain line looks good to the eye. I am running a shimano xt hub. Thee mechanic took it all apart greased and put back together. Anyone have trouble with skewers? My mechanic thinks its the hub and I should go to a s

  29. #29
    mtbr member
    Reputation:
    Join Date
    Dec 2011
    Posts
    14
    ss hub.

  30. #30
    mtbr member
    Reputation:
    Join Date
    Oct 2008
    Posts
    1,166
    It sounds to me like your rear cog is messed up. Are the teeth "shark toothed". Is it a singlespeed specific cog? Is the cog loose?

    I doubt it's the skewer, but if it does slide just a tiny bit (a mm or so), it is possible the chain could loosen just enough to pop off.

    A friend of mine once used a cog from a disassemble cassette (hyperglide) and he had this problem. Obviously, it was due to the ramped teeth on the cog.

  31. #31
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    714
    Try using a good cog or put a different wheel onand give out a whirl

  32. #32
    mtbr member
    Reputation:
    Join Date
    Jun 2006
    Posts
    7,816
    Is the chain coming off in the back or up front?

  33. #33
    mtbr member
    Reputation:
    Join Date
    Jan 2012
    Posts
    4,317
    How about new cogs, chain and a mechanic?

Members who have read this thread: 0

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2019 VerticalScope Inc. All rights reserved.