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

Hybrid 3x (flat bar) conversion to Road 3x (brifter) has me stumped

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.

Hybrid 3x (flat bar) conversion to Road 3x (brifter) has me stumped

Old 07-18-21, 09:35 PM
  #1  
ifixbikes
Junior Member
Thread Starter
 
Join Date: May 2021
Posts: 21
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Hybrid 3x (flat bar) conversion to Road 3x (brifter) has me stumped

Howdy folks. Today I was asked to convert a 3x Hybrid to a Road 3x and I thought it would be a no-brainer but I just couldn't get the Road 3x Front Derailleur to work perfectly.

Opus bike, original crank / chainrings were 42, 32, 22 - replacement cranks / chainrings are Ultegra 52, 39, 30 (I think?). The Alivio derailleur was not swapped as I thought it was capable of handling such a change.

I'm of an era which doesn't know a lot about the technical side of product differences but should a Triple FD not be capable of such a change? We also swapped from Trigger shifters to Brifter STI style...

Cable tension and routing... Check. F Derailleur alignment and height... check. DT Barrel adjustments done with slow and careful tweaking... Check. Still couldn't got all three to play well together.

I wish i had more info to offer. I'm sure your comments will stir my memory.

Thank you all in advance.
ifixbikes is offline  
Old 07-18-21, 10:29 PM
  #2  
Jeff Wills
Insane Bicycle Mechanic
 
Jeff Wills's Avatar
 
Join Date: Mar 2008
Location: other Vancouver
Posts: 9,561
Mentioned: 31 Post(s)
Tagged: 0 Thread(s)
Quoted: 684 Post(s)
Liked 332 Times in 221 Posts
Older Shimano triple front derailleurs used different amounts of cable pull for "road"vs. "mountain" setups. The Ultegra requires less pull than the Alivio so try it.
__________________
Jeff Wills

Comcast nuked my web page. It will return soon..
Jeff Wills is offline  
Likes For Jeff Wills:
Old 07-18-21, 10:50 PM
  #3  
Andrew R Stewart 
Senior Member
 
Andrew R Stewart's Avatar
 
Join Date: Feb 2012
Location: Rochester, NY
Posts: 15,172

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Raleigh Pro, Trek Cycle Cross, Mongoose tomac ATB, GT Bravado ATB, JCP Folder

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3011 Post(s)
Liked 1,336 Times in 934 Posts
I'll also add that road and MtB frt ders (by Shimano) have rather different chain ring sizes they are optimized for. Also some MtB cranks space their rings apart more then some road ones. Andy
__________________
AndrewRStewart
Andrew R Stewart is offline  
Old 07-18-21, 11:15 PM
  #4  
cpach
Senior Member
 
Join Date: Oct 2009
Location: Mt Shasta, CA, USA
Posts: 1,934

Bikes: Too many. Cannondale SuperSix, Trek Remedy 8, Trek Crossrip+ get the most ride time.

Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 443 Post(s)
Liked 215 Times in 171 Posts
Not compatible. You need a road triple fd, ideally designed for a 52t big ring (some are designed for 50t, you can probably get one to work but it'll be worse. )
cpach is offline  
Old 07-19-21, 05:33 AM
  #5  
shelbyfv 
Senior Member
 
shelbyfv's Avatar
 
Join Date: Jun 2007
Location: TN
Posts: 9,227
Mentioned: 32 Post(s)
Tagged: 0 Thread(s)
Quoted: 2604 Post(s)
Liked 2,917 Times in 1,547 Posts
Yes, be sure you get the FD that is designed for the 39t middle ring. Some are for 42t.
shelbyfv is offline  
Old 07-20-21, 08:33 PM
  #6  
ShannonM
Senior Member
 
Join Date: Jul 2020
Location: Humboldt County, CA
Posts: 596
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 276 Post(s)
Likes: 0
Liked 251 Times in 178 Posts
Originally Posted by shelbyfv View Post
Yes, be sure you get the FD that is designed for the 39t middle ring. Some are for 42t.
Distinction without a difference, IMHO.

I've never seen any Shimano road triple front derailleur not work on any non-weird triple crankset, including MTB cranks on 9 speed STI touring bikes, where 46/36/26 was pretty common stock gearing. Shimano didn't make a road triple FD that was "designed for" a 46T big ring, but lotsa Treks, Cannondales, and Surlys were built that way, and they shifted great.

Bicycle drivetrains are really forgiving, and specs are really conservative. Most combinations work so well that no rider in the world could tell the difference blindfolded. (Before they crashed.)

--Shannon
ShannonM is offline  
Old 07-22-21, 04:23 PM
  #7  
cpach
Senior Member
 
Join Date: Oct 2009
Location: Mt Shasta, CA, USA
Posts: 1,934

Bikes: Too many. Cannondale SuperSix, Trek Remedy 8, Trek Crossrip+ get the most ride time.

Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 443 Post(s)
Liked 215 Times in 171 Posts
Originally Posted by ShannonM View Post
Distinction without a difference, IMHO.

I've never seen any Shimano road triple front derailleur not work on any non-weird triple crankset, including MTB cranks on 9 speed STI touring bikes, where 46/36/26 was pretty common stock gearing. Shimano didn't make a road triple FD that was "designed for" a 46T big ring, but lotsa Treks, Cannondales, and Surlys were built that way, and they shifted great.

Bicycle drivetrains are really forgiving, and specs are really conservative. Most combinations work so well that no rider in the world could tell the difference blindfolded. (Before they crashed.)

--Shannon
I disagree-- it usually works fine, but the ease of setup and shift speed are noticeably better when matching the FD to the chainring set.
cpach is offline  
Old 07-22-21, 05:46 PM
  #8  
shelbyfv 
Senior Member
 
shelbyfv's Avatar
 
Join Date: Jun 2007
Location: TN
Posts: 9,227
Mentioned: 32 Post(s)
Tagged: 0 Thread(s)
Quoted: 2604 Post(s)
Liked 2,917 Times in 1,547 Posts
Yeah, when Shimano switched their road triples from 52-42-30 to 52-39-30, folks found the newer FD would not clear the 42t on the older cranks. And conversely the much shallower inner plate of the older FD did not do a good job pushing the chain off a 39t. Not a biggie if folks don't know this, was a long time ago. Maybe just a reminder that we can't know what we don't know.
shelbyfv is offline  
Old 07-22-21, 06:32 PM
  #9  
andrewclaus
Senior Member
 
Join Date: Feb 2012
Location: Golden, CO
Posts: 2,198

Bikes: 2016 Fuji Tread

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 472 Post(s)
Liked 226 Times in 166 Posts
It may not work in this case, but try clamping the cable on the other side of the pinch bolt.
andrewclaus is offline  
Old 07-22-21, 10:23 PM
  #10  
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Posts: 24,328

Bikes: Some silver ones, a red one, an orange one and a few titanium ones

Mentioned: 125 Post(s)
Tagged: 1 Thread(s)
Quoted: 4307 Post(s)
Liked 1,811 Times in 1,102 Posts
Originally Posted by cpach View Post
I disagree-- it usually works fine, but the ease of setup and shift speed are noticeably better when matching the FD to the chainring set.
I agree with ShannonM. The size of the chainring has little to do with how well a Shimano front derailer works. The cable pull is highly important but not the ring size. I just finished 1200 miles of touring with a Shimano Sora shifting a 44/32/20 XT external crank. It was shifting a 48/36/20 crank before I decided to reduce the gearing a bit. Set up was dead simple with no issues either with the 48 or 44 tooth ring.

One proviso: Set up and performance is generally easier and better, respectively, for Shimano’s cheaper front derailers. Tiagra and lower are easier to set up and have a wider useful range than the higher “better” Shimano derailers.

Ifixbikes: your issue is with the mountain bike vs road bike derailer. Swap to a road and everything should work.
__________________
Stuart Black
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
cyccommute is offline  
Likes For cyccommute:
Old 07-25-21, 09:37 PM
  #11  
Jeff Wills
Insane Bicycle Mechanic
 
Jeff Wills's Avatar
 
Join Date: Mar 2008
Location: other Vancouver
Posts: 9,561
Mentioned: 31 Post(s)
Tagged: 0 Thread(s)
Quoted: 684 Post(s)
Liked 332 Times in 221 Posts
Originally Posted by ShannonM View Post
Distinction without a difference, IMHO.

I've never seen any Shimano road triple front derailleur not work on any non-weird triple crankset, including MTB cranks on 9 speed STI touring bikes, where 46/36/26 was pretty common stock gearing. Shimano didn't make a road triple FD that was "designed for" a 46T big ring, but lotsa Treks, Cannondales, and Surlys were built that way, and they shifted great.

Bicycle drivetrains are really forgiving, and specs are really conservative. Most combinations work so well that no rider in the world could tell the difference blindfolded. (Before they crashed.)

--Shannon
Ah, but they did. The STX-RC front derailleur was designed for a 46/36/26 chainring set and a "road" front derailleur pull. I don't know if that was what was on the Treks and Cannondales you saw, but it's out there. Hard to find nowadays.
__________________
Jeff Wills

Comcast nuked my web page. It will return soon..
Jeff Wills is offline  
Old 07-25-21, 09:49 PM
  #12  
ShannonM
Senior Member
 
Join Date: Jul 2020
Location: Humboldt County, CA
Posts: 596
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 276 Post(s)
Likes: 0
Liked 251 Times in 178 Posts
Originally Posted by Jeff Wills View Post
Ah, but they did. The STX-RC front derailleur was designed for a 46/36/26 chainring set and a "road" front derailleur pull. I don't know if that was what was on the Treks and Cannondales you saw, but it's out there. Hard to find nowadays.
They very well might have been. The time frame would be about right, the front derailleur is the first part to get down-specced, and Shimano makes plenty of oddball parts for OEMs if the big ones ask for it. The scarcity of this particular front derailleur is evidence for it being an OEM-only part... every one ever made would have gone out attached to a bicycle, so there wouldn't be too many of them floating around.

Still, a good thing to have in the knowledge vault!

--Shannon
ShannonM 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 - 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.