Bent Chainring
#1
Thread Starter
Junior Member
Joined: Apr 2010
Posts: 18
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From: Cambridge, MA
Bikes: Surly Long Haul Trucker, Specialized Stupjumper, KHS Flite 800
Bent Chainring
Had to "thread the needle" last week and was unfortunate enough to be on the downstroke when I swerved and caught my pedal on the sidewalk curb HARD. I kept it together and avoided a potentially life-endangering scenario, but I noticed that I did bend my main sprocket a little bit. Now the wobble is enough to just fit within the boundaries of my front derailleur. The chain sometimes rubs against the edges of the cage depending on what gear I'm in. It doesn't look like I bent the frame, but I'm wondering if it's okay to run it like that, and if so for how long. Should I replace the crank or can I just get away with replacing the outer ring? I commute on the bike 14 miles round trip every day. My bike is a 2010 Surly Long Haul Trucker with what I believe is an Andel RSC6, 26/36/48t. Thanks.
Joe
Joe
#3
The Recumbent Quant

Joined: Jan 2012
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From: Fairfield, CT
Bikes: 2012 Cruzbike Sofrider, 2013 Cruzigami Mantis, 2016 Folding CruziTandem
If you can replace your chainrings (you can on most but not all cranks) AND the crank itself isn't bent (and there isn't play in the bottom bracket), then I'd try changing just the chainring. If something else is blown, then you've got to replace more.
#4
Mad bike riding scientist




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From: Denver, CO
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Had to "thread the needle" last week and was unfortunate enough to be on the downstroke when I swerved and caught my pedal on the sidewalk curb HARD. I kept it together and avoided a potentially life-endangering scenario, but I noticed that I did bend my main sprocket a little bit. Now the wobble is enough to just fit within the boundaries of my front derailleur. The chain sometimes rubs against the edges of the cage depending on what gear I'm in. It doesn't look like I bent the frame, but I'm wondering if it's okay to run it like that, and if so for how long. Should I replace the crank or can I just get away with replacing the outer ring? I commute on the bike 14 miles round trip every day. My bike is a 2010 Surly Long Haul Trucker with what I believe is an Andel RSC6, 26/36/48t. Thanks.
Joe
Joe
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Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Last edited by cyccommute; 11-05-13 at 11:54 AM.
#5
Banned
Joined: Jun 2010
Posts: 43,586
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From: NW,Oregon Coast
Bikes: 8
Andel is the Generic Crank QBP gets for their LHT build , so now you might look at an upgrade .
chainring bent?, take it off lay it on a flat tabletop..and see .. how much ..
You might have bent the crank spider..
whole crank bent. the pedal wont feel right as it goes around. too..
chainring bent?, take it off lay it on a flat tabletop..and see .. how much ..
You might have bent the crank spider..
whole crank bent. the pedal wont feel right as it goes around. too..
Last edited by fietsbob; 10-10-13 at 09:51 AM.
#6
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From: Omaha, NE
Bikes: 70s Miyata, 2013 GT Transeo 3.0, Cannondale Saeco
If it's only the chainring, I used a wrench to straighten one of mine. Slowly turn the crank and use the wrench to pull the chainring straight. Don't try to do it all in one pass. I think I did four or five passes to pull out a 1/8 to 1/4 inch bend on a mountain bike chainring that took a good hit. If you can take off the chainring it's easier to do with a hammer and a flat concrete surface. Look for cracks and replace it if needed.
#7
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If this was due to a pedal strike, I would double-check the crank-to-bottom bracket attachment (this is square taper, right?) before bending anything.
#8
Thread Starter
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Joined: Apr 2010
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From: Cambridge, MA
Bikes: Surly Long Haul Trucker, Specialized Stupjumper, KHS Flite 800
Thanks for all the replies to this thread. I brought it to the neighborhood repair shop, and apparently Surly sells a steel replacement outer ring that I'm having them put on this week. I'm going to have them check out the crank-to-bottom bracket area for any further damage as well.
#9
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Joined: Jan 2011
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From: NA
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Thanks for all the replies to this thread. I brought it to the neighborhood repair shop, and apparently Surly sells a steel replacement outer ring that I'm having them put on this week. I'm going to have them check out the crank-to-bottom bracket area for any further damage as well.





