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Old 01-16-08, 06:00 PM   #1
JoeWright
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Front R440 downshifts always to smallest

I bought some Shimano SL-R440-8 shifters a couple of months ago. The rear ****er is fine but the front one always shifts to the smallest cog on a single click, from any position (so it will move from largest to smallest on a single click). Surely this isn't right? Is there anything I can do to fix it?

It was new a couple of months ago and has always been like this.

Thanks, Joe
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Old 01-16-08, 06:24 PM   #2
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You may need to change the front derailleur, depending on what's on now. The cable tension may also be too tight.
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Old 01-16-08, 06:47 PM   #3
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Old 01-16-08, 07:50 PM   #4
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Originally Posted by pdq 5oh View Post
You may need to change the front derailleur, depending on what's on now.
How did you come to this conclusion?

OP: Does the shifter unit register the clicks? Is it defective? Determine this by disconnecting the cable and dry running it.

Also the most likely cause is too high cable tension. Learn how to adjust your FD here:

http://www.parktool.com/repair/readhowto.asp?id=75
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Old 01-16-08, 09:03 PM   #5
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I had the same problem with the flat-bar road shifter and front derailleur on my wife's old bike. I usually set up a front derailleur like this: shift to lowest gear, turn all barrel adjusters almost in, pull cable taught, attach cable to front derailleur bolt, and fine-tune with the barrel adjusters.

The problem I found is that it led to way too much cable tension. The FD would shift to the middle ring too soon--it would shift from using the half-shift trimming click. Then, when the shifter is put into the actual second gear spot, the chain then shifts to the outer ring. Then, when downshifting, it would always go back to the inner ring, even from the outer ring (because the shifter really thought it was in the middle ring).

The only way I could get around this is setting up the front derailleur so that there was a LOT of cable slack in the inner ring. But it was difficult because I had to find some seemingly arbitrary slackness (as opposed to just pulling it taught). It also rendered useless the trimming half-click (which just pulled the cable to about where it should have been starting anyway), but at least all the gears worked well.

I did find that using a regular drop-bar triple front derailleur (Sora, specifically) helped. There still had to be some slack in the cable, but not as much, so it was a little easier dialing it in.

Don't know if this is what's happening to you, but if your front shifter has a gear indicator, check where it goes for each gear and see if you're actually getting to the last position when in the outer ring. Also check if the shifter has the trimming half-shift going from first to second and determine if it is being used to move the chain a whole shift to the middle ring.

By the way, I'm assuming you're using flat-bar shifters with the FD. That FD is not supposed to be used with road shifters, like STI (though like I said before, for me, it didn't even work for its intended application).
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Old 01-16-08, 11:04 PM   #6
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What front der are you using. what shimano specs fo that shifet on a triple is r443a. The one thing about the derailuer is that you want the outer cage plate of the der to be parrallel to the chainrings (and just a mm or 2 above the outer chainring) instead of the inner cage plate

here is the link to the teck docs for the shifter. towards the bottom there is a trouble shootong chart that describes your problem
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Old 01-17-08, 01:56 AM   #7
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Quote:
Originally Posted by operator View Post
How did you come to this conclusion?

OP: Does the shifter unit register the clicks? Is it defective? Determine this by disconnecting the cable and dry running it.

Also the most likely cause is too high cable tension. Learn how to adjust your FD here:

http://www.parktool.com/repair/readhowto.asp?id=75
+1
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Old 01-17-08, 02:55 AM   #8
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I experienced this problem in a used Shimano FD shifter, It would upshift fine but tapping the downshift lever caused a 3 to 1 slammed shift.
After drowning the shifter in WD40, and working the levers with some tension on the cable, normal shifting returned. I believe the old lube jammed the downshift pawl.
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Old 01-17-08, 07:58 AM   #9
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Are you using the matching flat bar front derailleur. Flat bar shift levers have the same ratio as Shimano MTB shifters and require a matching FD.
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Old 01-17-08, 09:34 AM   #10
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Quote:
Originally Posted by operator View Post
How did you come to this conclusion?

OP: Does the shifter unit register the clicks? Is it defective? Determine this by disconnecting the cable and dry running it.

Also the most likely cause is too high cable tension. Learn how to adjust your FD here:

Quote:
Originally Posted by pdq 5oh View Post
The cable tension may also be too tight.
http://www.parktool.com/repair/readhowto.asp?id=75
Learn how to read.

BTW, when I put SRAM Attack shifters and flat bars on my road bike, I had the same problem while using the 105 front derailleur. I should have changed derailleurs as others here suggest. I merely lessened the cable tension. Or should I say set it less "high"?
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Old 01-17-08, 05:22 PM   #11
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Thanks for all the help everyone.

Yes, I made sure the derailler is the right one (Sora everything). I've diagnosed the following:

With cable unattached the shifter has five positions (two each for first two rings) and is happy. When connected, too tight and it reduces the number of positions (cannot shift to highest). I have to connect very loosely to get five shift positions put the first two shifts just take up the slack and don't move the derailluer.

So, it seems when attached tight enough so that the first and second upshifts actually do something, the shifter will fail to index to the highest gear. I've tried every minute adjustment available and I seem to be stuck between good indexing but poor movement, or good movement but incomplete indexing (so I can't shift onto highest chainring).

Any thoughts?

Thanks, Joe
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Old 01-17-08, 07:06 PM   #12
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Learn how to read.
Rolleyes yourself. Answer the ****ing question. I have no problems with the cable tension suggestion, i'd like to know why or how you reached the conclusion that the FD is the problem before cable tension is checked.

Learn how to read
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Old 01-17-08, 07:07 PM   #13
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Quote:
Originally Posted by JoeWright View Post
Thanks for all the help everyone.

Yes, I made sure the derailler is the right one (Sora everything). I've diagnosed the following:

With cable unattached the shifter has five positions (two each for first two rings) and is happy. When connected, too tight and it reduces the number of positions (cannot shift to highest). I have to connect very loosely to get five shift positions put the first two shifts just take up the slack and don't move the derailluer.

So, it seems when attached tight enough so that the first and second upshifts actually do something, the shifter will fail to index to the highest gear. I've tried every minute adjustment available and I seem to be stuck between good indexing but poor movement, or good movement but incomplete indexing (so I can't shift onto highest chainring).

Any thoughts?

Thanks, Joe
Are you sure you are clamping the cable correctly? The cable needs to go over the little nub next to the hex nut that secures the cable.
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Old 01-17-08, 07:08 PM   #14
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Quote:
Originally Posted by JoeWright View Post
Thanks for all the help everyone.

Yes, I made sure the derailler is the right one (Sora everything). I've diagnosed the following:

With cable unattached the shifter has five positions (two each for first two rings) and is happy. When connected, too tight and it reduces the number of positions (cannot shift to highest). I have to connect very loosely to get five shift positions put the first two shifts just take up the slack and don't move the derailluer.

So, it seems when attached tight enough so that the first and second upshifts actually do something, the shifter will fail to index to the highest gear. I've tried every minute adjustment available and I seem to be stuck between good indexing but poor movement, or good movement but incomplete indexing (so I can't shift onto highest chainring).

Any thoughts?

Thanks, Joe

A Sora derailleur is not the right one to use with these shifters....You need to use a derailleur from the R443 or 453 family. This is a road type front derailleur that responds to the cable pull of an MTB ratio shifter (the R440 is this ratio) A standard road FD (like Sora) does not move the proper amount.
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Old 01-17-08, 07:25 PM   #15
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Maddmaxx is right.

If you're running SORA (road) with 440 shifters it's not set up to work.

The only Shimano FD that will pull correctly on road cranks with flat bar shifters is the R443, or newer model 453. Usually its a case of a shifter simply telling the DR what to do, but in this instance thats not true. You need a different FD.
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Last edited by Monoborracho; 01-17-08 at 07:45 PM.
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Old 01-17-08, 09:37 PM   #16
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Operator, the two posts above are why I suggested the derailleur may be the problem. Does that answer your question?
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Old 01-18-08, 05:39 PM   #17
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Oh yes it is wrong. Thanks for pointing that out. Now I'm going off to cry.

Cheers everyone for your posts.

Joe
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