Bicycle Mechanics - Rear Derailleur cable: Clamp on inside or outside of bolt?

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Bevo Bill
11-10-08, 02:45 PM
When I'm stringing my rear derailleur (10sp DA) I thought I was supposed to clamp the cable on the in-board side of the clamp bolt. (As pictured)
http://www.fezzari.com/img/icons/DerailleurRearDuraAce.jpg

However I had the derailleur installed at the LBS, and the mechanic guy says "Oh yeah, it is better to clamp the cable on the outside of the bolt" -something about it tends to want to bend the pulleys into the spokes a little over time, even with the correct limit adjustment.
He also clipped of the little "finger" deal on the washer of the clamp bolt for some reason while doing this. It operates fine as is; but I'm wondering, is this guy full of crap? I mean Shimano designed it to be on the inside I think, so what the hell?

Anyone else ever heard of this?


roadfix
11-10-08, 02:51 PM
If the cable is not anchored on the correct side the derailleur will not index properly. Doing so alters the pull ratio.

onbike 1939
11-10-08, 02:55 PM
If you take off the clamp bolt you will see a serrated line below where the cable is supposed to be run.


Bevo Bill
11-10-08, 02:56 PM
Strange. I have ridden the bike as-is with it clamped on the "wrong" side, and it works perfectly fine, contrary to 'conventional widsom'. So given that, I haven't bothered to change it back to the "correct" side, yet. I suppose I'll change it back soon enough.

I was really just wondering if anyone had ever heard of a similar suggestion, or if there is truth to this rumor.

dvs cycles
11-10-08, 07:05 PM
I just installed one a few hours ago. Directions specifly say the way in the picture is the way to do it.
Mine works just great that way and I'm sure Shimano intends it that way.

vettefrc2000
11-10-08, 07:18 PM
When I'm stringing my rear derailleur (10sp DA) I thought I was supposed to clamp the cable on the in-board side of the clamp bolt. (As pictured)
http://www.fezzari.com/img/icons/DerailleurRearDuraAce.jpg

However I had the derailleur installed at the LBS, and the mechanic guy says "Oh yeah, it is better to clamp the cable on the outside of the bolt" -something about it tends to want to bend the pulleys into the spokes a little over time, even with the correct limit adjustment.
He also clipped of the little "finger" deal on the washer of the clamp bolt for some reason while doing this. It operates fine as is; but I'm wondering, is this guy full of crap? I mean Shimano designed it to be on the inside I think, so what the hell?

Anyone else ever heard of this?

Full of crap? Yes, most definitely. That is one of the reasons I have a full set of shop tools.:mad:

FWI...I would go back and make them give me replacement hardware.

operator
11-10-08, 07:44 PM
When I'm stringing my rear derailleur (10sp DA) I thought I was supposed to clamp the cable on the in-board side of the clamp bolt. (As pictured)
http://www.fezzari.com/img/icons/DerailleurRearDuraAce.jpg

However I had the derailleur installed at the LBS, and the mechanic guy says "Oh yeah, it is better to clamp the cable on the outside of the bolt" -something about it tends to want to bend the pulleys into the spokes a little over time, even with the correct limit adjustment.
He also clipped of the little "finger" deal on the washer of the clamp bolt for some reason while doing this. It operates fine as is; but I'm wondering, is this guy full of crap? I mean Shimano designed it to be on the inside I think, so what the hell?

Anyone else ever heard of this?

That is a load of ****.

I cringed when you mentioned that he actually modified the washer cable is supposed to run under. What a ****ing idiot.

Panthers007
11-10-08, 08:10 PM
Well this seems to have fit nicely. It's an Ultegra:

http://i424.photobucket.com/albums/pp323/nagognog/IMG_0087.jpg

mechBgon
11-10-08, 08:16 PM
Well this seems to have fit nicely. It's an Ultegra:

http://i424.photobucket.com/albums/pp323/nagognog/IMG_0087.jpg

Your washer is 90° counterclockwise of its intended orientation, but you have the cable on the correct side of the bolt.

Panthers007
11-10-08, 08:28 PM
I'm aware. However it's more stable in this position. So chock one up for Shimano's loopy. And one up for the LBS mentioned above being mostly loopy.

mechBgon
11-10-08, 08:40 PM
I'm aware. However it's more stable in this position. So chock one up for Shimano's loopy. And one up for the LBS mentioned above being mostly loopy.

Actually, the reason for Shimano's orientation is that the bent tab gives the cable a definite fulcrum point, as you can see if you look at the photo of the Dura-Ace derailleur in the first post. But it should work adequately well regardless :beer: Yeah, the original post had me shaking my head at the LBS in question.

roadfix
11-10-08, 08:44 PM
Actually, the reason for Shimano's orientation is that the bent tab gives the cable a definite fulcrum point, as you can see if you look at the photo of the Dura-Ace derailleur in the first post.Ahh, that makes total mechanical sense. I always wondered what the purpose of that tab was for.

dperreno
11-10-08, 08:48 PM
Call me crazy but I thought the tab was simply to prevent the washer from rotating as you tighten the bolt...

operator
11-10-08, 08:57 PM
Call me crazy but I thought the tab was simply to prevent the washer from rotating as you tighten the bolt...

This is exactly what it is for.

dperreno
11-10-08, 09:12 PM
This is exactly what it is for.

Aha! So I AM Crazy... they were right after all!

mechBgon
11-10-08, 09:23 PM
Call me crazy but I thought the tab was simply to prevent the washer from rotating as you tighten the bolt...

edit: after a closer look, I think you guys are correct, it's to prevent rotation. The cable doesn't rest against the tab when it's in its intended groove. Sorry for my goof-up, I must've had Campy on the brain :P

firereign
11-10-08, 09:34 PM
If it works, whats the big deal?!?!

mechBgon
11-10-08, 09:57 PM
BTW, Bevo Bill, the replacement cable-anchor assembly is Quality Bicycle Products #DP7727 for the Dura-Ace version (with aluminum washer), if you feel like having them get you one. Otherwise you can order one from Harris Cyclery: http://harriscyclery.net/page.cfm?PageID=49&action=details&sku=DP7727

roadfix
11-10-08, 10:06 PM
I better just stick to riding my fixed gear bikes.....:p :D

maddmaxx
11-11-08, 03:59 AM
If you use the tab on the washer as a point to pull the cable against, then you will not pull it up tight against the threads of the anchor screw. If you don't pull it up aginst the screw threads, then you will not ding the screw threads or cable when tightening the screw.

Cable position, inside or outside of the screw does make a small difference in the indexing of the derailleur. Its enough to make the difference between so/so and perfect shifting.

Generally, you will find that the major manufacturers have spent serious time designing their equipment and that following their diagrams or instructions will provide pretty good results.

Bevo Bill
11-11-08, 04:54 AM
Ok, thanks all for the confirmation. I actually went and changed it back to the correct side now.

I'd consider going back to the shop to vent and get reparations; but I don't think I'm that persnickety
( http://www.maplewoodbicycle.com/ ) <----I'll just name names
I haven't been back to them since.