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

Advice pls. Going from a 12-32 to 12-36 Tiagra 4600 10 speed... Doable?

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.

Advice pls. Going from a 12-32 to 12-36 Tiagra 4600 10 speed... Doable?

Old 06-03-13, 12:40 AM
  #1  
Member
Thread Starter
 
Join Date: Oct 2012
Posts: 49
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Advice pls. Going from a 12-32 to 12-36 Tiagra 4600 10 speed... Doable?

Before a 42 mile ride Memorial day, I thought a 32 in the back would be enough to conquer the hills. As it stands, it wasn't. So I've been thinking of swapping out the rear for something bigger to help with hills. My riding buddies tell me the 4600 setup I have now will handle the 36t without changing the chain or derailleur. I was wondering if anyone here could offer advice. Thanks in advance!
creonte is offline  
Old 06-03-13, 12:56 AM
  #2  
Senior Member
 
Join Date: Dec 2011
Location: Santa Cruz, Ca
Posts: 427
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
If you are using a mountain derailleur like a deore then you should be fine with a 36. The chain may or may not be fine depending on how long it is on your bike now (if it's as loose as possible on the small small combo then it should be ok).

I don't think there is a tiagra 12-36 cassette though. I think the biggest is a 12-30 and after that you need a mountain cassette or SRAM cassette.

If you have a shimano road derailleur I doubt you will be able to make a 12-36 cassette work but you can always try and see if the derailleur pulley touches the largest cog with the b-trim adjusted all the way in.
aramis is offline  
Old 06-03-13, 12:59 AM
  #3  
Senior Member
 
Join Date: Oct 2007
Location: West Yorkshire, United Kingdom
Posts: 5,773
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 454 Post(s)
Liked 104 Times in 87 Posts
Would need to measure the chain, but would be very surprised if you can make a chain which was cut for a 12-32 stretch to a 36t. For the cassette, again not convinced, from running GS MTB RD's have found they don't like 34t cassettes that much, and you are far better off with a SGS RD.

Without knowing what you have on the front (crank ratios) or current RD spec, it's hard to clarify any of this, more info would be useful.
jimc101 is offline  
Old 06-03-13, 06:37 AM
  #4  
Member
 
Join Date: Jan 2010
Posts: 27
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked 1 Time in 1 Post
A 12-36 10sp cassette with RD4600 rear is pushing it. If your derailleur hanger is long enough it might work. You would be better off with a 9sp RD-M592 which is designed to shift a 12-36 cassette. Keep in mind that Shimano 10 sp road shifters are compatible with Shimano 9sp MTB rear derailleurs.
fun2none is offline  
Old 06-03-13, 10:44 AM
  #5  
Member
Thread Starter
 
Join Date: Oct 2012
Posts: 49
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by jimc101
Would need to measure the chain, but would be very surprised if you can make a chain which was cut for a 12-32 stretch to a 36t. For the cassette, again not convinced, from running GS MTB RD's have found they don't like 34t cassettes that much, and you are far better off with a SGS RD.

Without knowing what you have on the front (crank ratios) or current RD spec, it's hard to clarify any of this, more info would be useful.
Thanks for your help, sorry I should have gave more specs. I have a compact up front, 50/34. It's a Fuji 1.1C Sportif.
creonte is offline  
Old 06-03-13, 11:30 AM
  #6  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,938

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 141 Post(s)
Tagged: 1 Thread(s)
Quoted: 5899 Post(s)
Liked 2,767 Times in 1,546 Posts
You need 2 more links to wrap the back half of the 36t (vs 32t) sprocket. If your chain was already cut as short as possible, you need to lengthen it, otherwise you'll be fine.

It's easy enough to know before changing anything. Shift to the big/big combination, and lift the chain away from the bottom of the chainring and pull it forward 4 teeth. 2 teeth because you need them, and the 2nd 2 teeth to confirm the required slack for shifting, ie big/big+2 formula.

If you can pull it farward almost 4 links you're OK, but less than 3 links you need to lengthen.

BTW- by link I mean 1/2", not 1" as in a pair of links.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is online now  
Old 06-03-13, 11:40 AM
  #7  
Senior Member
 
Join Date: Apr 2007
Posts: 6,841
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 1135 Post(s)
Liked 1,236 Times in 783 Posts
To summarize:

You'll need a MTB cassette, Sram or Shimano
You'll need a Shimano 8 or 9 (NOT 10) speed mountain rear derailleur
You'll probably need a longer chain

Perfect candidate for a road triple in the front, but I'd bet it was neither offered, considered, maybe not even available by the bike shop when you bought the bike. A negative turn in the bike marketing biz in the past 5 years, IMHO. 5 or 6 years ago, you would have much more likely had that option. Making that change (crank, shifters) now would be more expensive than what you have in mind.

For that it's worth, my wife's bike has a MTB RD and an 11-36 (maybe 34, can't remember) on the back with Tiagra shifters. It works GREAT, and she's very happy with it. But she has that cassette AND a road triple with a 30t small ring. She's never complained nor been ashamed about the super low gearing!

Last edited by Camilo; 06-03-13 at 11:52 AM.
Camilo is offline  
Old 06-03-13, 04:25 PM
  #8  
Member
Thread Starter
 
Join Date: Oct 2012
Posts: 49
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Thank you all very much! I really contemplated going for a triple up front, but my research and advice from others that a compact double would do the job here in SoCal. Looks like my best bet while figuring out what to do with gears is HTFU. Cheers!
creonte is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Vexxer
Bicycle Mechanics
3
05-08-16 11:16 AM
PartsMan
Bicycle Mechanics
10
10-30-13 01:27 PM
coolvm11
Road Cycling
10
08-20-12 12:16 PM
lucky1976
Touring
16
01-09-12 02:48 PM
kidcymucks
Bicycle Mechanics
15
10-10-11 06:19 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.