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

Rear Derailleur and Cassette questions

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.

Rear Derailleur and Cassette questions

Old 05-07-16, 06:44 PM
Senior Member
Thread Starter
Join Date: May 2014
Location: Fuquay Varina, NC (Research Triangle)
Posts: 269

Bikes: 2016 Fuji Gran Fondo 2.0 LE, Specialized Tricross Elite Disc (2013), Motobecane 529HT

Likes: 0
Liked 0 Times in 0 Posts
Rear Derailleur and Cassette questions

Two cassette/rear derailleur questions.

I have a 10sp tiagra equipped bike, currently with a 12/30 cassette. I would like to go towards a more climbing oriented cassette. What ratio cassettes could I use with the current derailleur? If I want to go even more climbing oriented, could I change the derailuer (10sp Deore) too and still have it work with the STI shifters as they are?

Also have an 11sp Ultegra equipped bike, I do NOT want to put MTB derailiers or cassettes on it, but I am wondering if I can not go a little more climbing oriented then the current 11/25.
Vexxer is offline  
Old 05-08-16, 06:51 AM
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.

Likes: 0
Liked 3 Times in 3 Posts
Shimano data sheet will give you all the ranges you can use with present RD arm length, simple rule bigger cassette, longer RD arm length.

Another option rather than doing the RD way to to drop the small chain ring a few teeth.
Bike tinker man is offline  
Old 05-08-16, 07:22 AM
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656

Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!

Likes: 0
Liked 1,099 Times in 745 Posts
If you need a significantly bigger big cog, you will need an MTB rear derailleur but it will have to be a 9-speed rear derailleur. Shimano 10-speed road and 10-speed MTB shifters and derailleurs are not compatible. Shimano's 9-speed MTB rear derailleurs work perfectly with 10-speed road shifters.

BTW, what are the chainrings on your crank? Perhaps modifying, or even replacing it, may be less expensive than chaining both the rear derailleur and cassette.

Your Ultegra bike will certainly take a 11x28 cassette.
HillRider is offline  
Old 05-08-16, 11:16 AM
Senior Member
andr0id's Avatar
Join Date: Feb 2009
Posts: 2,522
Likes: 0
Liked 7 Times in 5 Posts
A 12-30 is a very climbing oriented cassette. If you're in good health under 50, you should be able to go up a brick wall with that.

The standard 11 speed Ultegra RD will support up to 28 max with the 50x34 compact front.
andr0id is offline  
Related Topics
Thread Starter
Last Post
Bicycle Mechanics
10-24-13 12:29 PM
Cyclocross and Gravelbiking (Recreational)
06-17-13 02:19 PM
Bicycle Mechanics
06-03-13 04:25 PM
01-09-12 02:48 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 - Your Privacy Choices -

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