Quick Q re: '90s Deore DX fd anatomy
10-03-21, 03:16 PM
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Quick Q re: '90s Deore DX fd anatomy
Hey all. Rather than spending an hour screwing (see what I did there?) up my alignment, can someone please tell me which is the L-limit screw? The derailleur works perfectly, except when I'm shifting into the small ring, the chain can fall off. Park Tools told me how to do it, just need to know which one. Thanks.
10-03-21, 04:49 PM
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Hey all. Rather than spending an hour screwing (see what I did there?) up my alignment, can someone please tell me which is the L-limit screw? The derailleur works perfectly, except when I'm shifting into the small ring, the chain can fall off. Park Tools told me how to do it, just need to know which one. Thanks.
https://www.youtube.com/watch?v=ZNG7g83lI-s&t=465s
https://www.youtube.com/watch?v=ZNG7g83lI-s&t=465s
Starting at 3:38 in the video Calvin presents how to identify the L-limit screw(bolt actually).
An additional option is the installation of one of these:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
My GF had the occasional habit of shifting into the small chainring very fast and the chain would go past the ring(even with a well adjusted DR)..the chain catcher eliminated the issue..at least it hasn't happened since I installed it. This may be due to the chain catcher or may be due to changed shifting habits..no idea.
10-03-21, 05:24 PM
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As long as the limit screws are well adjusted, I dont see how any sort of shifting, fast, poor etc would cause the chain to fall off.
not all derailleurs mark which limit screw is L or H. I can't remember if the L is the inner or outer screw, so hopefully someone can chime in to confirm.
The easiest thing to do (easier than even making a thread about this) woukd be to play around with both of them and watch which way the cage moves as you turn the screw. It shouldn't take you any more than 2 minutes to get it right.
not all derailleurs mark which limit screw is L or H. I can't remember if the L is the inner or outer screw, so hopefully someone can chime in to confirm.
The easiest thing to do (easier than even making a thread about this) woukd be to play around with both of them and watch which way the cage moves as you turn the screw. It shouldn't take you any more than 2 minutes to get it right.
10-03-21, 06:53 PM
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The low limit screw is the one closest to the seat tube.
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10-03-21, 07:04 PM
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10-03-21, 09:33 PM
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As long as the limit screws are well adjusted, I dont see how any sort of shifting, fast, poor etc would cause the chain to fall off.
not all derailleurs mark which limit screw is L or H. I can't remember if the L is the inner or outer screw, so hopefully someone can chime in to confirm.
The easiest thing to do (easier than even making a thread about this) woukd be to play around with both of them and watch which way the cage moves as you turn the screw. It shouldn't take you any more than 2 minutes to get it right.
not all derailleurs mark which limit screw is L or H. I can't remember if the L is the inner or outer screw, so hopefully someone can chime in to confirm.
The easiest thing to do (easier than even making a thread about this) woukd be to play around with both of them and watch which way the cage moves as you turn the screw. It shouldn't take you any more than 2 minutes to get it right.
bad chainline
warped ring(s)
gnarled tooth or teeth
wrong ramp and pin clocking
cage orientation- toe in, toe out
bent cage
max Displacement between big and small ring beyond the cage shape
probably more
10-04-21, 11:50 AM
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Thanks BradH and dedhed , that's my derailleur! Well, a cleaner version of mine. 
10-04-21, 01:21 PM
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Note that Top Swing front derailers position the hi- and lo-limit screws backwards, with hi-limit on the left.
Of course most road FD's are traditional, bottom-swing, but the RSX was one that was top-swing, and with the limit screws reversed.
Of course most road FD's are traditional, bottom-swing, but the RSX was one that was top-swing, and with the limit screws reversed.
