Go Back  Bike Forums > Bike Forums > Singlespeed & Fixed Gear
Reload this Page >

Converted bike, chain falls off

Search
Notices
Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

Converted bike, chain falls off

Thread Tools
 
Search this Thread
 
Old 06-19-12, 11:18 PM
  #1  
Playing catch up
Thread Starter
 
Mayday.JP's Avatar
 
Join Date: Jul 2010
Location: The Best Coast, CA
Posts: 121

Bikes: Felt F4

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Converted bike, chain falls off

I'm posting this to inquire for my brother. I've personally never have had much experience with single speed bikes and my brother recently got an old peugot 9 speed bike and he took the gears off to make a single speed. He got the fixed wheel rear tire but the geared crankset stayed. The chain stays on fine but after a few mins or riding, it comes off everytime. We've tried tightening the chain, loosening it up but it falls off everytime. He's getting frustrated because he's had it for a few months and can't seem to fix it. Would the solution be to get a single speed crankset or is there something else we can try?

Also, he has the single speed chain he bought as well.

Thanks
Mayday.JP is offline  
Old 06-19-12, 11:23 PM
  #2  
Fixie Infamous
 
Nagrom_'s Avatar
 
Join Date: Dec 2011
Location: SF
Posts: 10,474

Bikes: 2007 CAAD Optimo Track, 2012 Cannondale CAAD10, 1996 GT Force restomod, 2015 Cannondale CAADX

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Likes: 0
Liked 4 Times in 4 Posts
Sounds like the front chainring is worn, and the chainline is probably off.
Nagrom_ is offline  
Old 06-19-12, 11:38 PM
  #3  
We win all charity rides
 
Street rider's Avatar
 
Join Date: Apr 2008
Location: Central Michigan University/ GR, MI
Posts: 3,369

Bikes: BMX, fixed gear

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
My first thought was chainline. Maybe try putting it on a different cog of the cassette?
Street rider is offline  
Old 06-20-12, 06:22 AM
  #4  
Crawler
 
linus's Avatar
 
Join Date: Apr 2005
Location: OH~ CANADA
Posts: 1,410
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 211 Post(s)
Liked 20 Times in 15 Posts
Chainline it is.....
linus is offline  
Old 06-20-12, 07:08 AM
  #5  
Senior Member
 
nuhtowel's Avatar
 
Join Date: Nov 2010
Location: State College, PA
Posts: 812

Bikes: Caad9, Fixed gear, Hardrock beater, 3 speed cruiser

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
you might be able to get away with getting a bottom bracket that has a spindle length of around 110
nuhtowel is offline  
Old 06-20-12, 08:31 AM
  #6  
Senior Member
 
Bat56's Avatar
 
Join Date: May 2010
Location: St.Paul, MN
Posts: 1,822
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 47 Post(s)
Liked 4 Times in 3 Posts
If fixing the cabin line doesn't work, look at the chainring and make sure it not bent.

I don't think it's the frame, but it could be some serious flexing taking place. Are you guys sumo wrestlers?
Bat56 is offline  
Old 06-29-12, 09:23 AM
  #7  
Senior Member
 
m4rx12's Avatar
 
Join Date: Mar 2011
Location: Canada
Posts: 150

Bikes: Peugot 1980 Road FG Convert

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Look up a chart which explains how many spacers you need to align chain. Also pics would help.
m4rx12 is offline  
Old 06-29-12, 09:36 AM
  #8  
Your cog is slipping.
 
Scrodzilla's Avatar
 
Join Date: May 2009
Posts: 26,053
Mentioned: 41 Post(s)
Tagged: 0 Thread(s)
Quoted: 640 Post(s)
Liked 100 Times in 58 Posts
Originally Posted by Bat56
If fixing the cabin line doesn't work, look at the chainring and make sure it not bent.
Definitely the cabin line. I had a crooked cabin line once and it was a real ***** to deal with!
Scrodzilla is offline  
Old 06-29-12, 09:49 AM
  #9  
pro in someone's theory
 
prooftheory's Avatar
 
Join Date: Jul 2011
Location: Las Cruces, NM
Posts: 3,236

Bikes: FTP

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 72 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Cupertino from cbain.
prooftheory is offline  
Old 06-29-12, 09:59 AM
  #10  
Senior Member
 
chas58's Avatar
 
Join Date: Jul 2010
Location: Michigan
Posts: 4,863

Bikes: too many of all kinds

Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 1147 Post(s)
Liked 415 Times in 335 Posts
what cog is he using? A good FG cog is designed so the chain stays on the cog. If you used a cog from a multi-speed cassette, it is designed for you to easily shift gears (not good if you only have one gear).
chas58 is offline  
Old 06-29-12, 11:29 AM
  #11  
``````````````
 
CaptainCool's Avatar
 
Join Date: Feb 2007
Location: san jose
Posts: 763
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by Bat56
If fixing the cabin line doesn't work, look at the chainring and make sure it not bent.
Check the spindle too -- see if the chainring wobbles left to right at all when you spin the crank. My old bike had a slightly bent spindle, and the chain went from overtight to a bit too slack in each turn of the crank.
CaptainCool is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Lebowski
Bicycle Mechanics
12
10-20-21 06:07 PM
patata
Bicycle Mechanics
6
09-06-14 02:22 PM
Tycho Brahe
Road Cycling
9
02-18-13 09:30 AM
lazybee
Bicycle Mechanics
7
09-20-10 09:55 AM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.