Go Back  Bike Forums > Bike Forums > Tandem Cycling
Reload this Page >

Why no idler wheels on tandems?

Notices
Tandem Cycling A bicycle built for two. Want to find out more about this wonderful world of tandems? Check out this forum to talk with other tandem enthusiasts. Captains and stokers welcome!

Why no idler wheels on tandems?

Old 05-07-22, 06:15 PM
  #1  
fooferdoggie 
Senior Member
Thread Starter
 
Join Date: Jan 2020
Posts: 2,343
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 679 Post(s)
Liked 945 Times in 552 Posts
Why no idler wheels on tandems?

with long wheel recumbents and long chains why not use this method instead of having to retake the bottom bracket? it would be far easier to deal with and easier to fix or take off a chain.
fooferdoggie is offline  
Old 05-08-22, 02:39 AM
  #2  
jccaclimber
Senior Member
 
Join Date: May 2005
Location: SFBay
Posts: 2,334

Bikes: n, I would like n+1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 127 Post(s)
Likes: 0
Liked 133 Times in 108 Posts
Originally Posted by fooferdoggie
with long wheel recumbents and long chains why not use this method instead of having to retake the bottom bracket? it would be far easier to deal with and easier to fix or take off a chain.
As someone who had built a few recumbents and ridden a lot more, many of them have absolutely appalling chain management.

Other than old or really cheap frames, tandems tend not to have them for the same reason fixed gear bikes don’t. The lower chain portion can end up in tension, which tends to be hard on the idlers. Most also want the chain length to be fixed, IE no rear derailer type idlers. Without the fixed length chain the sync between captain and stoker floats a bit and the top can lose tension.
Finally, a half decently made eccentric is more secure and less easily damaged than an idler.

Don’t get me started on plastic tubes being used as chain guides.
jccaclimber is offline  
Likes For jccaclimber:
Old 05-09-22, 05:22 PM
  #3  
Leisesturm
Senior Member
 
Join Date: Jul 2005
Posts: 5,968
Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 2473 Post(s)
Liked 722 Times in 513 Posts
The main issue is that there needs to be a way to fine tune the tension in the system to allow for 'chain stretch. The previous answer is correct in so far as the need to have tension on the return run of chain, but an idler could allow for that.The horrible tension adjusters fitted on department store TSO's are, in fact, idlers in a sliding carrier. The *usually) extremely small diameter of the pulley wheel, and the overall lack of refinement of such designs makes it easy to overlook that this is actually an idler system at work.
Leisesturm is offline  
Old 05-10-22, 01:25 AM
  #4  
jccaclimber
Senior Member
 
Join Date: May 2005
Location: SFBay
Posts: 2,334

Bikes: n, I would like n+1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 127 Post(s)
Likes: 0
Liked 133 Times in 108 Posts
It isn’t just that it needs some tension to not derail. It’s also that the captain backpedaling makes the lower chain portion a high tension segment rather than just a slack tension segment.
jccaclimber is offline  
Old 05-11-22, 08:19 PM
  #5  
Carbonfiberboy 
just another gosling
 
Carbonfiberboy's Avatar
 
Join Date: Feb 2007
Location: Everett, WA
Posts: 19,500

Bikes: CoMo Speedster 2003, Trek 5200, CAAD 9, Fred 2004

Mentioned: 115 Post(s)
Tagged: 0 Thread(s)
Quoted: 3872 Post(s)
Liked 1,920 Times in 1,369 Posts
IMO an absolutely tight chain between captain and stoker is a must. Each rider needs to be able to feel the pedaling of the other rider. I think that conventional timing chains have too much slack. When we changed from a chain to a tight Gates belt, it made a big improvement to our pleasure-in-togetherness we get on the tandem. An idler pulley would make it much worse.
__________________
Results matter
Carbonfiberboy is offline  
Old 05-12-22, 07:29 PM
  #6  
headwind15
Bikeable
 
headwind15's Avatar
 
Join Date: Jan 2011
Posts: 326
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 173 Post(s)
Likes: 0
Liked 104 Times in 73 Posts
I was a bicycle store owner for over 12 years and used to sell tandems, some of the less expensive ones had idler wheels (Crestline tandems come to mind), The truth is one thing is for sure: Idler wheels are really, really really noisy. Trust me, I you want a half way decent tandem, you don't want one with idler wheels)
headwind15 is offline  
Likes For headwind15:
Old 05-19-22, 11:35 AM
  #7  
Chilepines
Junior Member
 
Join Date: Jul 2020
Location: New Hampshire
Posts: 194

Bikes: 1984 homemade 531SL road bike; 1988 Ritchey TimberComp; 1997 Nashbar tandem; 1998 Kona Explosif; Specialized Epic, Scott CR1 Pro; Salsa Beargrease; Curtlo custom Tandem, Curtlo custom S3 steel gravel bike.

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 67 Post(s)
Liked 49 Times in 37 Posts
Interesting observation about the timing chain being a way for the captain and stoker to communicate. We have a timing chain (as most do) and have no problem at all telling what the other is doing. Maybe that comes from riding the tandem together for many years. And if I don't get the message through the cranks there are other less subtle ways to communicate!
Chilepines is offline  
Old 05-20-22, 09:50 AM
  #8  
MNBikeCommuter
Senior Member
 
MNBikeCommuter's Avatar
 
Join Date: Nov 2010
Location: Minnesota
Posts: 852

Bikes: Cannondale '92 T600 '95 H600 '01 RT1000

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 89 Post(s)
Liked 104 Times in 80 Posts
Originally Posted by Chilepines
Interesting observation about the timing chain being a way for the captain and stoker to communicate. We have a timing chain (as most do) and have no problem at all telling what the other is doing. Maybe that comes from riding the tandem together for many years. And if I don't get the message through the cranks there are other less subtle ways to communicate!
I came upon this realization several years after beginning riding with my main two stokers: my kids. We got going when they were 9 and 11 so they adopted my style right from the start. I hadn't realized how automatic things were until there'd be an occasional break from the routine pedaling--I might have a false start with pedaling and have to back off right away and they weren't expecting it, etc. My dad joined me on many rides too and our style was so similar it was the same with him--no words needed.

The one time I remember having to explicitly yell something was riding up a steep hill in the South Dakota Badlands with my son. I was trying to drop into the granny gear but he wasn't catching my backing off just a little and I couldn't shift!
MNBikeCommuter is offline  
Old 01-25-23, 10:18 PM
  #9  
RoulezTandem
Newbie
 
Join Date: Apr 2022
Location: New England
Posts: 37
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 4 Times in 3 Posts
Our S&S-coupled custom steel framed tandem has an idler wheel. It is necessary to permit removal of timing chain during disassembly for each trip's transport in two pieces in our truck.
After fighting to spin off tensioned chain for a while on our new build, we ground and welded a mount and added the sprung idler.


Last edited by RoulezTandem; 02-07-23 at 11:34 AM.
RoulezTandem 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 -

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