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


Go Back   > >

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.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 04-06-13, 08:29 PM   #1
phorn
Junior Member
Thread Starter
 
Join Date: Aug 2010
Bikes:
Posts: 18
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Shimano 22-32-44 Conversion to 26-36-44 - Any Issues?

With a Shimano 9-speed crankset that came as a 22-32-44 triple, are there any issues with the front derailleur or shifting if I replace the inner and middle chainrings to turn this into a 26-36-44 setup? While the spacing between rings will remain the same, I wondered if lesser differential between the new 36T middle and existing 44T outer ring would cause any problems. Thanks.
phorn is offline   Reply With Quote
Old 04-06-13, 08:36 PM   #2
Bill Kapaun
Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Bikes: 86 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.
Posts: 9,496
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 125 Post(s)
You MIGHT have to raise the FDER slightly to clear the smaller rings.

I changed my 22-32-44's to a 22-32-36 & 22-32-38.
I had to leave the FDER @ the 44T setting because going lower caused interference with the middle ring. Didn't get far enough to see if it had problems with the smallest. Looks gawdawful, but shifts-

Attached Images
File Type: jpg 579334_3854305559402_1187894027_n.jpg (56.4 KB, 7 views)

Last edited by Bill Kapaun; 04-06-13 at 08:42 PM.
Bill Kapaun is offline   Reply With Quote
Old 04-06-13, 08:37 PM   #3
Continuity
Senior Member
 
Join Date: Mar 2013
Location: NW UK
Bikes: 1992 Marin Eldridge Grade, 2007 Kona PHD and 199? Trek 1000 (current build project)
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Should be OK - FDs are usually specified by the *maximum* tooth difference they will support, and the largest chainring.
Continuity is offline   Reply With Quote
Old 04-06-13, 08:49 PM   #4
dddd
Ride, Wrench, Swap, Race
 
dddd's Avatar
 
Join Date: Jan 2010
Location: Northern California
Bikes: Cheltenham-Pederson racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Posts: 5,069
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
I've also encountered the problem with contact with the middle ring, even when the tooth difference was a full (but only) 10t.

The idea of raising the derailer higher than the recommended height (relative to the big ring) is asking for overshift imo, and of course now you'll be shifting over a non-matched set of rings, yet another ding to the overall rubustness of this setup.
dddd is offline   Reply With Quote
Old 04-06-13, 09:04 PM   #5
Continuity
Senior Member
 
Join Date: Mar 2013
Location: NW UK
Bikes: 1992 Marin Eldridge Grade, 2007 Kona PHD and 199? Trek 1000 (current build project)
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Hmm - I must have always been really lucky with this, especially with my 1992 Marin MTB with it's elderly Shimano DX FD - I've had all sorts of ring combos on it, including the 50/38/26 that's on there now which is shifting beautifully.
Continuity is offline   Reply With Quote
Old 04-08-13, 01:47 AM   #6
dddd
Ride, Wrench, Swap, Race
 
dddd's Avatar
 
Join Date: Jan 2010
Location: Northern California
Bikes: Cheltenham-Pederson racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Posts: 5,069
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Quote:
Originally Posted by Continuity View Post
Hmm - I must have always been really lucky with this, especially with my 1992 Marin MTB with it's elderly Shimano DX FD - I've had all sorts of ring combos on it, including the 50/38/26 that's on there now which is shifting beautifully.
Yes, the older, pre-compact front mtn derailers were a whole lot more tolerant, and thus more versatile. Trek even spec'd these for road triples in the late 1980's.

When the chainring standard for the XT gruppo started to include the 12-tooth 32-44t gap, they "deepened" the cage, making the inner cage plate taller. This taller cageplate would contact the tips of the middle ring's teeth on any crank with only a 10t difference between the largest two cogs.
The cage plate wouldn't hit the granny ring's teeth though, despite there often being only a 10t difference between the small and middle rings, because the cage travels in an arc and not in a straight line.

I think the taller cage plates were needed to compensate for the slower chain speed and higher chain tension of the smaller "compact" rings, helping the front derailer to push the chain more solidly and aggressively to a larger ring.
dddd is offline   Reply With Quote
Old 04-08-13, 06:10 AM   #7
Continuity
Senior Member
 
Join Date: Mar 2013
Location: NW UK
Bikes: 1992 Marin Eldridge Grade, 2007 Kona PHD and 199? Trek 1000 (current build project)
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by dddd View Post
Yes, the older, pre-compact front mtn derailers were a whole lot more tolerant, and thus more versatile. Trek even spec'd these for road triples in the late 1980's.

When the chainring standard for the XT gruppo started to include the 12-tooth 32-44t gap, they "deepened" the cage, making the inner cage plate taller. This taller cageplate would contact the tips of the middle ring's teeth on any crank with only a 10t difference between the largest two cogs.
The cage plate wouldn't hit the granny ring's teeth though, despite there often being only a 10t difference between the small and middle rings, because the cage travels in an arc and not in a straight line.

I think the taller cage plates were needed to compensate for the slower chain speed and higher chain tension of the smaller "compact" rings, helping the front derailer to push the chain more solidly and aggressively to a larger ring.
That's really interesting to know - thanks for posting that.

I think I might just 'stock up' on as much of the older 7/8 speed Shimano gear as I can when I get some money to do so - I absolutely love the old DX-level stuff - seemed just as good as XT (which was top-of-the-line before they introduced XTR), and incredibly durable. Their modern stuff just seems a lot weaker and not as well-made, even though it looks 'blingy'.

Last edited by Continuity; 04-08-13 at 06:13 AM.
Continuity is offline   Reply With Quote
Old 04-08-13, 11:08 AM   #8
phorn
Junior Member
Thread Starter
 
Join Date: Aug 2010
Bikes:
Posts: 18
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks a lot for everyone's input. I think it sounds like it is at least worth a try to go with the 26-36-44 setup. If I run into clearance issues, the worst that will happen is the need to get a 48T outer ring...
phorn 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 02:37 PM.