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

Turning a triple into a single?

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.

Turning a triple into a single?

Old 10-09-07, 06:54 PM
  #1  
Bolo Grubb
Senior Member
Thread Starter
 
Bolo Grubb's Avatar
 
Join Date: Jun 2004
Location: Tucson, AZ
Posts: 1,889

Bikes: 1984 Trek 720 with a Nexus hub, 2016 Cannondale Synapse

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 34 Post(s)
Liked 17 Times in 10 Posts
Turning a triple into a single?

is it as simple as pulling off 2 of the chain rings?

I have a 1984 trek 720 tour bike. I am going to put a Nexus hub on the rear but hoping to save a little money by using the existing crank and BB. Is it possible to just pull off the smallest and largest chain ring?
Bolo Grubb is offline  
Old 10-09-07, 06:54 PM
  #2  
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Posts: 28,353

Bikes: 1987 Bianchi Campione

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Likes: 0
Liked 23 Times in 17 Posts
Assuming teh chainline is correct to the middle ring and your rear hub.
operator is offline  
Old 10-09-07, 07:26 PM
  #3  
lukeC
Senior Member
 
Join Date: Feb 2007
Posts: 139
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Of the triples I've seen the Large and Middle Chainrings are usually held on at the same point with "longer" Double Chainring Bolts and the smallest or granny ring will be held on at a smaller BCD point.

you can pull of the small one easily. However if you want to just use one of the larger/middle the Chainring bolts you have will be too long.

- You will need to either shorten the chainring bolts (hacksaw or grinder) or buy some single Chainring bolts. (BMX / Track bike ones)

- and aggree with the above - you can have issues with getting a straight chainline.
lukeC is offline  
Old 10-10-07, 07:02 PM
  #4  
Bottomfeeder
Mr. cost-benefit analysis
 
Join Date: Dec 2005
Location: Agua Dulce, CA
Posts: 437

Bikes: Surly Crosscheck Single Speed, Novara 9 speed commuter/runabout

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
If your chainring bolt are too long once the outboard chainring is removed you can do 1 of 3 things.

1: buy some shorter chainring bolts from some niche webstore.

2: file the existing bolts and nuts down. (hope you have a bench grinde or at least a vice and decent file.) I've done this both with and without a vice for my various single speed projects.

3: go down to the hardware store and pick up some nylon spacers to use as 'washers' on the existing bolts. I did this as a 'temporary' fix when converting my wife's triple crank to a single to work with an internally geared hub. I assumed they would wear out somehow and I'd have to eventually do a 'better fix'. Well that was 3 years ago, and they look like they'll last as long as I don't monkey with 'em.

DanO
Bottomfeeder is offline  
Old 10-10-07, 07:07 PM
  #5  
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Posts: 28,353

Bikes: 1987 Bianchi Campione

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Likes: 0
Liked 23 Times in 17 Posts
Originally Posted by Bottomfeeder View Post
If your chainring bolt are too long once the outboard chainring is removed you can do 1 of 3 things.

1: buy some shorter chainring bolts from some niche webstore.
They're not niche. Ever heard of a fixed gear? Short stack, bmx chainring bolts are a'plenty. At $5 A set, filing down chainring bolts is a serious waste of time, same goes for your washer method.
operator is offline  
Old 10-10-07, 09:35 PM
  #6  
fiver
Senior Member
 
Join Date: Apr 2005
Location: Eugene OR
Posts: 130

Bikes: VooDoo Limba, 2000 GF Kai Tai, old lugged fixies

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by operator View Post
They're not niche. Ever heard of a fixed gear? Short stack, bmx chainring bolts are a'plenty. At $5 A set, filing down chainring bolts is a serious waste of time, same goes for your washer method.
Well...I was going to recommend removing the teeth from the outer ring to make yourself a chain guard, and reusing the bolts at the same time, but it sounds like that would be a "waste of time".

ps: it's not kind to insult those offering you their opinions. I have been a mechanic for a long time and the previous posts are all good ideas.
fiver is offline  
Old 10-10-07, 10:24 PM
  #7  
Bottomfeeder
Mr. cost-benefit analysis
 
Join Date: Dec 2005
Location: Agua Dulce, CA
Posts: 437

Bikes: Surly Crosscheck Single Speed, Novara 9 speed commuter/runabout

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Yea. Kinda hostile there Operator. Usually I've seen short bolts for a bit more than that - https://www.webcyclery.com/product.ph...cat=406&page=1. In fact, If you've got a source for those $5 a set bolts I'd like to pick some up to have on hand. Then again, those 5 nylon spacers probably came in just under a buck down at the Do It Center. And perhaps once in a while spending a half hour at the vice with a file and a cold one is just what the doctor ordered.

DanO
Bottomfeeder is offline  
Old 10-11-07, 06:50 PM
  #8  
fiver
Senior Member
 
Join Date: Apr 2005
Location: Eugene OR
Posts: 130

Bikes: VooDoo Limba, 2000 GF Kai Tai, old lugged fixies

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Bottomfeeder View Post
And perhaps once in a while spending a half hour at the vice with a file and a cold one is just what the doctor ordered.
word
fiver is offline  
Old 10-11-07, 10:52 PM
  #9  
erader
Senior Member
 
erader's Avatar
 
Join Date: Feb 2006
Location: silicon valley
Posts: 1,774
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
erader is offline  

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


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell or Share My Personal Information -

Copyright © 2023 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.