Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Folding Bikes Discuss the unique features and issues of folding bikes. Also a great place to learn what folding bike will work best for your needs.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 12-11-16, 02:42 PM   #1
jp_nyc
IndyFab girl
Thread Starter
 
jp_nyc's Avatar
 
Join Date: May 2005
Bikes: IF Crown Jewel, Giro track, Brompton M3
Posts: 154
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Is 9sp chain compatible with 3sp drivetrain on Brompton?

Question in subject line. Thanks! JP
jp_nyc is offline   Reply With Quote
Old 12-11-16, 04:46 PM   #2
Joe Remi
Senior Member
 
Join Date: Jan 2010
Location: NorCal
Bikes: Haibike Sduro Trekking SL, Rivendell Appaloosa, Concinnity singlespeed, KHS mini velo (Japan market), Trident Spike trike
Posts: 587
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 181 Post(s)
Quote:
Originally Posted by jp_nyc View Post
Question in subject line. Thanks! JP
The answer is..probably if your Brommie uses 3/32" derailleur-type chains, but it appears some 3-speeds use 1/8. I suspect you wouldn't be asking if you didn't already have the chain handy, so might as well throw it on there and see what happens. Good luck!

http://www.bikebrompton.com/accesorios.aspx?Id=chains
Joe Remi is offline   Reply With Quote
Old 12-11-16, 04:56 PM   #3
jp_nyc
IndyFab girl
Thread Starter
 
jp_nyc's Avatar
 
Join Date: May 2005
Bikes: IF Crown Jewel, Giro track, Brompton M3
Posts: 154
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
I'm pretty sure I need 3/32 chain for the Brompton. Problem is I can't find the width for SRAM PC-971 chain anywhere.
jp_nyc is offline   Reply With Quote
Old 12-11-16, 05:30 PM   #4
jur
Senior Member
 
Join Date: May 2005
Location: Melbourne
Bikes:
Posts: 7,293
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 239 Post(s)
Quote:
Originally Posted by jp_nyc View Post
I'm pretty sure I need 3/32 chain for the Brompton. Problem is I can't find the width for SRAM PC-971 chain anywhere.
Any multi-speed chain should work as long as the cogs can accept 3/32" chains. Multi-speed chains are 3/32" inside spacing, only the outside width changes.

You may need to adjust the chain pusher end-stop screws slightly to compensate for the narrower chain.
jur is offline   Reply With Quote
Old 12-12-16, 09:19 AM   #5
12boy
Senior Member
 
12boy's Avatar
 
Join Date: Oct 2012
Location: casper wy usa
Bikes: brompton sl, surly steamroller, fuji track, gary fisher bmx minivelo etc
Posts: 267
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 83 Post(s)
I have found the cheaper chains work best for me. By that I mean KMC and SRAM 7-8 speed chains.I used a higher end chain designed for 9-10 speeds which did not sit all the way down on the rear cogs although the chain ring was fine. Kept clean and lubed they last quite a while, at least here in the high desert.
12boy is offline   Reply With Quote
Old 12-12-16, 09:57 AM   #6
leoho5
Senior Member
 
Join Date: Jul 2011
Bikes:
Posts: 124
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
The SRAM PC-971 is a 9 speed chain so it should have a width between 6.6-6.8 mm. It is a 3/32" chain so it should work with your 3-speed Brompton.
leoho5 is offline   Reply With Quote
Old 12-12-16, 10:17 AM   #7
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 8
Posts: 27,996
Mentioned: 60 Post(s)
Tagged: 0 Thread(s)
Quoted: 2867 Post(s)
No. ... but you could Measure it..


Now you can order S-A replacement cogs in 3 or 4/32, Brompton Stock is 1/8.

years ago Sachs of Germany made the 1st 3 by 2 hubs for Brompton UK . those were thinner, 13t and a 15t, that skipped every 4th tooth

so had (spares are still stocked) 3 incomplete teeth to help it shift between the 2 cogs.





...

Last edited by fietsbob; 12-12-16 at 10:33 AM.
fietsbob is offline   Reply With Quote
Old 12-12-16, 10:32 AM   #8
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 8
Posts: 27,996
Mentioned: 60 Post(s)
Tagged: 0 Thread(s)
Quoted: 2867 Post(s)
I've been using a full bushing 3/32" chain* .. the type is longer wearing than Derailleur chains.. On a skip tooth 15t, 12 full teeth, 3 short ..

* it was an OldStock find, from Harris Cycles, in Newton MA..




...
fietsbob is offline   Reply With Quote
Old 12-12-16, 03:02 PM   #9
leoho5
Senior Member
 
Join Date: Jul 2011
Bikes:
Posts: 124
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Looks like 3-speed Bromptons may come with 1/8" cogs after looking at SJS's website. Best off to measure your cog to see if it 1/8" or 3/32" as already suggested.
leoho5 is offline   Reply With Quote
Old 12-12-16, 06:48 PM   #10
12boy
Senior Member
 
12boy's Avatar
 
Join Date: Oct 2012
Location: casper wy usa
Bikes: brompton sl, surly steamroller, fuji track, gary fisher bmx minivelo etc
Posts: 267
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 83 Post(s)
Mine came with a 3/32. it is, however,at least 3 years old. I don't know how to tell how old they are, perhaps from the SN or some such? It could have sat around the bike store for years. it was originally a single speed.
12boy is offline   Reply With Quote
Old 12-29-16, 12:47 AM   #11
Rick Imby
Senior Member
 
Join Date: Sep 2015
Bikes:
Posts: 567
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 203 Post(s)
Just put the chain on and you will know instantly if you are going to need a 1/8" chain. The 3/32 will not sit down on the cog if you need a 1/8".
Rick Imby is offline   Reply With Quote
Old 12-29-16, 10:52 PM   #12
keyven
Senior Member
 
Join Date: Oct 2013
Location: Singapore
Bikes: Fully customized 11-spd MTB built on 2014 Santa Cruz 5010 frame; Brompton S2E-X 2014; Brompton M3E 2014
Posts: 1,132
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Newer Brompton come with 3/32" chains, but I think pre-2012 or something 1 and 3-spds were standard 1/8", while 2 and 6-spds were 3/32".
keyven is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 07:41 PM.


 
  • Ask a Question
    get answers from real people!
Click to start entering your question.
I HAVE A QUESTION