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

A mountain bike derailleur on a road bike?

Notices
Road Cycling “It is by riding a bicycle that you learn the contours of a country best, since you have to sweat up the hills and coast down them. Thus you remember them as they actually are, while in a motor car only a high hill impresses you, and you have no such accurate remembrance of country you have driven through as you gain by riding a bicycle.” -- Ernest Hemingway

A mountain bike derailleur on a road bike?

Old 12-22-11, 07:40 PM
  #1  
Bioluminescence
Still a newb.
Thread Starter
 
Bioluminescence's Avatar
 
Join Date: May 2011
Location: Northern IL
Posts: 451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
A mountain bike derailleur on a road bike?

Specifically a SRAM X.4 replacing an older (2004?) Sora one. My assumption is that the mountain bike derailleurs would be able to handle a higher stress, such as those exerted in sprints. But a few questions, 1) Would I even see an improvement going from my current to the new? 2) Are Shimano Sora shifters even compatible with this derailleur? 3) Would it even be worth it?

I know it's a bit of a stupid upgrade, but the derailleur are only $25, so figure it might be a way to upgrade a little...
Bioluminescence is offline  
Old 12-22-11, 07:45 PM
  #2  
Capecodder
Senior Member
 
Capecodder's Avatar
 
Join Date: Jul 2010
Location: Somewhere Between The Beginning And The End
Posts: 1,994
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
SRAM has a different pull ratio than Shimano..... SRAM 1:1 Shimano 2:1 Will not work..

Last edited by Capecodder; 12-22-11 at 07:51 PM.
Capecodder is offline  
Old 12-22-11, 07:47 PM
  #3  
Clem von Jones
Senior Member
 
Join Date: Sep 2008
Posts: 652
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 150 Post(s)
Liked 14 Times in 12 Posts
A mountain bike derailleur is a good idea if you live in the mountains, ride dirt trails, or plan on touring with this bicycle because they'll fit 34 and 36 tooth cassettes but I'd go with a Deore to make it compatible with your brifters. If your chain jumps or hangs up when you apply a lot of torque it's probably a bad chain-line problem, worn chain and gears, or maladjusted derailleur. You might be cross-shifting too. To fix the chainline you could change your bottom bracket spindle to make the chainline straight in your favorite gears. Check your front derailleur travel to see if its possible first.

Last edited by Clem von Jones; 12-22-11 at 08:04 PM.
Clem von Jones is offline  
Old 12-22-11, 09:24 PM
  #4  
2ndGen
CAADdict
 
2ndGen's Avatar
 
Join Date: Jul 2009
Location: BF Heaven
Posts: 6,756

Bikes: 2009 Cannondale CAAD9-?

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Get a new one road specific rear derailleur:
Sora: $30.
105: $50.
Ultegra: $75.
Problem solved.
(cut those prices in half for used)

2ndGen is offline  
Old 12-22-11, 09:33 PM
  #5  
CPcyclist
Senior Member
 
CPcyclist's Avatar
 
Join Date: Jul 2004
Location: Wisconsin
Posts: 1,646

Bikes: Lemond Arrivee, Felt F1 Road, Tomac Revolver(full), GT race (hardtail)

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
if you feel the need (want to have wider gearing) to do the mountain derailleur the go with Shimano XT for the reason above. Don't do the mountain because in your mind it is more durable not true for that go with the Ultegra or 105 road derailleur.
CPcyclist is offline  
Old 12-22-11, 09:37 PM
  #6  
gregf83 
Senior Member
 
Join Date: Jun 2008
Location: Vancouver, BC
Posts: 9,202
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1185 Post(s)
Liked 286 Times in 174 Posts
Originally Posted by Bioluminescence View Post
My assumption is that the mountain bike derailleurs would be able to handle a higher stress, such as those exerted in sprints.
That would be an incorrect assumption. Sprinting doesn't stress a derailleur and MTB derailleurs aren't any tougher they're just designed to accommodate a wider range of gearing.
gregf83 is offline  
Old 12-22-11, 09:38 PM
  #7  
Bioluminescence
Still a newb.
Thread Starter
 
Bioluminescence's Avatar
 
Join Date: May 2011
Location: Northern IL
Posts: 451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Capecodder View Post
SRAM has a different pull ratio than Shimano..... SRAM 1:1 Shimano 2:1 Will not work..
Originally Posted by Clem von Jones View Post
A mountain bike derailleur is a good idea if you live in the mountains, ride dirt trails, or plan on touring with this bicycle because they'll fit 34 and 36 tooth cassettes but I'd go with a Deore to make it compatible with your brifters. If your chain jumps or hangs up when you apply a lot of torque it's probably a bad chain-line problem, worn chain and gears, or maladjusted derailleur. You might be cross-shifting too. To fix the chainline you could change your bottom bracket spindle to make the chainline straight in your favorite gears. Check your front derailleur travel to see if its possible first.
Originally Posted by 2ndGen View Post
Get a new one road specific rear derailleur:
Sora: $30.
105: $50.
Ultegra: $75.
Problem solved.
(cut those prices in half for used)

Originally Posted by CPcyclist View Post
if you feel the need (want to have wider gearing) to do the mountain derailleur the go with Shimano XT for the reason above. Don't do the mountain because in your mind it is more durable not true for that go with the Ultegra or 105 road derailleur.
Thanks guys! Will work on finding a cheaper used road one. I have all winter anyways...
Bioluminescence is offline  
Old 12-22-11, 10:33 PM
  #8  
2ndGen
CAADdict
 
2ndGen's Avatar
 
Join Date: Jul 2009
Location: BF Heaven
Posts: 6,756

Bikes: 2009 Cannondale CAAD9-?

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Bioluminescence View Post
Thanks guys! Will work on finding a cheaper used road one. I have all winter anyways...
Winter's a great time to buy.
You can get a new rear derailleur at a ridiculously low price.
2ndGen is offline  
Old 12-22-11, 10:33 PM
  #9  
Bioluminescence
Still a newb.
Thread Starter
 
Bioluminescence's Avatar
 
Join Date: May 2011
Location: Northern IL
Posts: 451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by 2ndGen View Post
Winter's a great time to buy.
You can get a new rear derailleur at a ridiculously low price.
Both new and used? I'll be roaming CL for the next few months.
Bioluminescence is offline  
Old 12-22-11, 10:56 PM
  #10  
2ndGen
CAADdict
 
2ndGen's Avatar
 
Join Date: Jul 2009
Location: BF Heaven
Posts: 6,756

Bikes: 2009 Cannondale CAAD9-?

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Bioluminescence View Post
Both new and used? I'll be roaming CL for the next few months.
I'd get "new", but if you're on a budget,
then get something that's used that's in great condition.
Granted, you won't get a warranty with it and it's a chance you take.

$28./shipped -----> https://www.ebay.com/itm/Shimano-Sora...#ht_2117wt_886

For "used", you can trust the guys here... https://www.bikeforums.net/forumdispl...ke-Marketplace

(you might get lucky and get another deal like this... https://www.bikeforums.net/showthread...es)-Components )
2ndGen is offline  
Old 12-22-11, 11:36 PM
  #11  
LesterOfPuppets
cowboy, steel horse, etc
 
LesterOfPuppets's Avatar
 
Join Date: Sep 2008
Location: Valley of the Sun.
Posts: 37,584

Bikes: everywhere

Mentioned: 67 Post(s)
Tagged: 1 Thread(s)
Quoted: 7751 Post(s)
Liked 2,819 Times in 1,531 Posts
I have MTB rear derailers on both my road bikes ATM and only one of them has a triple. Like others have said the're not especially tougher but they open up the opportunity to get a lower geared cogset and along with new left shifter and front derailer and crankset you could go triple.

MTB RD can't be Sram, though.
LesterOfPuppets is online now  
Old 12-23-11, 02:08 AM
  #12  
BarracksSi
Bike ≠ Car ≠ Ped.
 
BarracksSi's Avatar
 
Join Date: Jul 2007
Location: Washington, DC
Posts: 13,861

Bikes: Some bikes. Hell, they're all the same, ain't they?

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 4 Times in 3 Posts
Switched from a Tiagra RD to an XT (a Shadow version, I believe) specifically to run a "pie plate" 11-32 cassette on my 9sp Tiagra-equipped commuter. Works great.
BarracksSi is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
gregf83
Bicycle Mechanics
2
11-01-15 10:45 PM
tcoffey
Bicycle Mechanics
9
02-20-14 10:56 AM
IntoTheWild
Bicycle Mechanics
1
10-06-11 06:21 PM
mcgyver74
Bicycle Mechanics
5
06-14-11 03:05 PM
maverick31210
Mountain Biking
15
04-07-11 03:01 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


Thread Tools
Search this Thread

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

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.