Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Sunrace 7-speed cassette tog cog slipping?

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Sunrace 7-speed cassette tog cog slipping?

Old 10-24-10, 12:00 PM
  #1  
Kid A
Thread Starter
 
TurbineBlade's Avatar
 
Join Date: Aug 2009
Location: Alexandria, VA
Posts: 1,778
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 5 Times in 5 Posts
Sunrace 7-speed cassette tog cog slipping?

Hey, I just installed a new cassette - a sunrace 7-speed and new 7-speed "Z" chain (kmc) with huge 34t granny cog jump at the bottom of the cassette. I use friction shifters and all the cogs work just fine except the smallest one....which the chain skips over repeatedly.

I have the derailleur high limit dialed in just fine, so I know it's not that the chain is just unable to reach the cog properly. Since I don't ever use an 11t cog on any of my bikes (and only seldom use the 12 or 13), I plan to just dial the high limit to avoid the smallest cog.

What would cause this nonsense? I've gone through 4-5 cassettes on this set-up in the last couple of years and never seen this happen.

Thanks,
TurbineBlade is offline  
Old 10-24-10, 02:42 PM
  #2  
Senior Member
 
DannoXYZ's Avatar
 
Join Date: Jul 2005
Location: Saratoga, CA
Posts: 11,736
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 109 Post(s)
Liked 9 Times in 6 Posts
How is it slipping? It is rubbing on the next cog over? Is it riding on top of the teeth?

Isolating the cause to either lateral or longitudinal movements can help pinpoint where the problem may be.
DannoXYZ is offline  
Old 10-24-10, 03:21 PM
  #3  
Kid A
Thread Starter
 
TurbineBlade's Avatar
 
Join Date: Aug 2009
Location: Alexandria, VA
Posts: 1,778
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 5 Times in 5 Posts
Sure. It is (was) riding on top of the teeth, not really trying to drop one way or the other.....which is what I thought at first when I was dialing the high-limit...thinking maybe it was trying to jump into the drop out or not getting enough lateral movement to make it onto the smallest cog.

I dialed the little sucker so it won't even drop onto the smallest cog now, but I was just wondering what the deal was with it since the other 6 cogs engage the chain just normal.
TurbineBlade is offline  
Old 10-24-10, 03:37 PM
  #4  
Senior Member
 
bikeman715's Avatar
 
Join Date: Mar 2008
Location: Salinas , Ca.
Posts: 2,646

Bikes: Bike Nashbar AL-1 ,Raligh M50 , Schwinn Traveler , and others

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 85 Post(s)
Liked 2 Times in 2 Posts
You may have your cable to tight. lossen it just a little and the chain should drop in.
bikeman715 is offline  
Old 10-24-10, 05:07 PM
  #5  
Kid A
Thread Starter
 
TurbineBlade's Avatar
 
Join Date: Aug 2009
Location: Alexandria, VA
Posts: 1,778
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 5 Times in 5 Posts
Nope, definitely not that...I just tried to loosen the barrel adjuster on the rear derailleur to "extremely loose" and it still rides on top of the small cog.

Weird -- setting high limit back to locking-out that sucker .
TurbineBlade is offline  
Old 10-24-10, 05:16 PM
  #6  
Senior Member
 
bikeman715's Avatar
 
Join Date: Mar 2008
Location: Salinas , Ca.
Posts: 2,646

Bikes: Bike Nashbar AL-1 ,Raligh M50 , Schwinn Traveler , and others

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 85 Post(s)
Liked 2 Times in 2 Posts
you sure your hanger is straight ? it could be off just a mm and that can throw everything off.
bikeman715 is offline  
Old 10-24-10, 06:14 PM
  #7  
Member
 
Join Date: Apr 2008
Posts: 36
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Is the chain on the middle or big chainring when you are shifting into the 11 tooth cog? If you're in the granny gear the chainline may be too far off for the chain to engage the cog.
bikemedic is offline  
Old 10-25-10, 12:37 AM
  #8  
Senior Member
 
DannoXYZ's Avatar
 
Join Date: Jul 2005
Location: Saratoga, CA
Posts: 11,736
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 109 Post(s)
Liked 9 Times in 6 Posts
Originally Posted by TurbineBlade
Nope, definitely not that...I just tried to loosen the barrel adjuster on the rear derailleur to "extremely loose" and it still rides on top of the small cog.

Weird -- setting high limit back to locking-out that sucker .
Look underneath the cog where the chain moves from the top-pulley to the cog. Is the chain in-line with the cog? Or is it at an angle. Take a picture from directly behind the smallest cog with the chain riding on it for us to see. I suspect it has something to do with the derailleur positioning.
DannoXYZ is offline  
Old 10-25-10, 06:53 AM
  #9  
Kid A
Thread Starter
 
TurbineBlade's Avatar
 
Join Date: Aug 2009
Location: Alexandria, VA
Posts: 1,778
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 5 Times in 5 Posts
Update - problem solved. I'm an idiot.

The lock ring for the cassette was too large (diameter) and was interferring with the smallest cog on this particular cassette. I guess the lock ring I was using came from an older cassette with a 13t cog compared to the smaller 11t this one has.

I had some other lockrings and got it working fine.
TurbineBlade is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Weizilla
Bicycle Mechanics
14
05-07-21 09:56 PM
Countdown48
Bicycle Mechanics
10
04-20-16 11:54 AM
masi61
Classic & Vintage
6
07-24-15 12:53 PM
LeicaLad
Bicycle Mechanics
22
01-22-15 09:31 PM
swapmeet
Bicycle Mechanics
2
05-05-11 11:58 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


Thread Tools
Search this Thread

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.