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

New chain ring questions

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.

New chain ring questions

Old 01-06-17, 12:32 AM
  #1  
Senior Member
Thread Starter
 
Join Date: Apr 2011
Posts: 1,337
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 70 Post(s)
Liked 13 Times in 9 Posts
New chain ring questions

My bike has compact crank Rival 50/34 and I find that 50 is too high. I bought a used 46 chainring on auction site and it came with a plastic piece, but where does it go? Also there is one hole with some strange markings inside like something should go inside. It is different than the other holes because those are smooth.

I don't know what this piece is for. The numbers on the ruler are cm, smaller lines are 0.5mm.





Does something go in this bolt eye?
jsdavis is offline  
Old 01-06-17, 02:58 AM
  #2  
Senior Member
 
Join Date: Oct 2007
Location: West Yorkshire, United Kingdom
Posts: 5,773
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 453 Post(s)
Liked 104 Times in 87 Posts
Have you asked the seller? you may get the answer there!
jimc101 is offline  
Old 01-06-17, 09:12 AM
  #3  
Full Member
 
Join Date: Dec 2014
Location: Retired to Penang Malaysia originally from UK
Posts: 346

Bikes: My 1978 Raleigh from new, 1995 Trek, & constant changing & rebuilding of other bike projects.

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
Yes obviously ask the seller, no comment on the rubber bush grommet, the other photo to me is too close up to understand, as you say it's on the chain ring ? take another photo not so close: maybe I'm missing the point.
Bike tinker man is offline  
Old 01-06-17, 09:40 AM
  #4  
Senior Member
 
Andrew R Stewart's Avatar
 
Join Date: Feb 2012
Location: Rochester, NY
Posts: 17,960

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4153 Post(s)
Liked 3,751 Times in 2,245 Posts
The serrations in the ring bolt hole are artifacts from a female half of the ring bolt and nut which had serrations in it's outer surface to better grip the ring hole. More common on cranks that have the 5th hole positioned behind the crank arm, as it's hard to get a ring nut wrench in there.


The plastic bit looks a lot like a plug for some hole. At about 4mm in diameter (for the "shaft") I suspect it's meant to fit in a M% threaded hole. maybe a bottle cage boss. Anyway I doubt it's intended to be used on the ring, likely just was along for the ride in the packaging. Andy.
Andrew R Stewart is offline  
Old 01-06-17, 03:57 PM
  #5  
Senior Member
Thread Starter
 
Join Date: Apr 2011
Posts: 1,337
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 70 Post(s)
Liked 13 Times in 9 Posts
Originally Posted by Andrew R Stewart
The serrations in the ring bolt hole are artifacts from a female half of the ring bolt and nut which had serrations in it's outer surface to better grip the ring hole. More common on cranks that have the 5th hole positioned behind the crank arm, as it's hard to get a ring nut wrench in there.


The plastic bit looks a lot like a plug for some hole. At about 4mm in diameter (for the "shaft") I suspect it's meant to fit in a M% threaded hole. maybe a bottle cage boss. Anyway I doubt it's intended to be used on the ring, likely just was along for the ride in the packaging. Andy.
Ok - you are exactly right about the serrations in the bolt eye. From what I can find, my chainring has a nut pressed into the bolt eye because one of the bolt is hidden by the arm. Apparently it is common to Sram 22 speed systems. I had no noticed one bolt eye is hidden until now. I guess Sram tried to make it look like Shimano and FSA 4 bolt system.

The seller just buys stuff from sales like garage sales and then sells on auction site. She does not know the origin of the plastic plug.
jsdavis is offline  
Old 01-07-17, 01:24 PM
  #6  
Senior Member
 
TallRider's Avatar
 
Join Date: Oct 2005
Location: Fresno, CA
Posts: 4,454
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 128 Post(s)
Likes: 0
Liked 12 Times in 10 Posts
If you are able to bolt the 46t chainring on correctly, I'd be very surprised if the rubber piece played a meaningful role in the chainring function.
TallRider is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Pendergast
Road Cycling
47
10-05-20 08:18 AM
rodscot
Bicycle Mechanics
4
10-30-16 02:58 AM
Dfrost
Bicycle Mechanics
2
05-28-16 09:27 PM
Davebo
Bicycle Mechanics
12
11-13-14 02:15 PM
MTBaddict
Bicycle Mechanics
1
02-10-10 07:56 PM

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.