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Is the front derailleur supposed to move pretty much parallel?

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Is the front derailleur supposed to move pretty much parallel?

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Old 07-22-09, 09:32 AM
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Is the front derailleur supposed to move pretty much parallel?

Hi, recently picked up an old Diamonback X-link MTB. Front derailleur is a Deore, top swing, (top pull, if that matters) and I think it might be out of whack.

When you click it over to the big ring, the aft end of the cage is sticking farther outboard than the front end of the cage. In the middle ring, the cage is parallel to the ring. And in the small ring, the aft end of the cage is farther inboard than the forward end.

Never noticed any of my other bikes ever doing this. Is this thing bent?

Thanks for any help.
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Old 07-22-09, 10:08 AM
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Maybe. Outer plate of FD should be parallel to the plane of the CW in all three positions.
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Old 07-22-09, 10:17 AM
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That's what I was thinking... time to hit ebay for a cheap replacement.
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Old 07-22-09, 11:00 AM
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Don't jump the gun and buy a new one without trying to realign it first.
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Old 07-22-09, 11:59 AM
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Agreed^^^ - Don't just buy another without trying it after a re-installation. Starting from square 1. is the best way to solve most every FD problems. This is a cut & paste giving an outline of what to do:

Take the cable off the FD. Now install it from scratch as per Park Tool Repair:

https://www.parktool.com/repair/readhowto.asp?id=75

And BicycleTutor:

https://bicycletutor.com/adjust-front-derailer/

When you have it properly trimmed and are ready for the cable - a new one wouldn't hurt - you want to pull the cable taut - not too tight, taut. Then apply 48 to 60 inch-pounds to the pinch-bolt. Then put it through it's paces.

It's always easier and faster to install a FD from square-one, than it is to make adjustments with it already attached. This tends to fix one thing - while throwing another out of kilter. Start fresh. You'll get it.

Adding a barrel-adjuster can solve many problems with the cable coming loose - or being too tight.
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Old 07-22-09, 12:34 PM
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The problem is, it's aligned "too far inward" in the small ring and "too far outward" in the big ring:


I can't see how to adjust out that bad travel.
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Old 07-23-09, 01:09 AM
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Originally Posted by Phantoj
I can't see how to adjust out that bad travel.
It's bent and/or a pivot point is broken. I think what DieselDan meant is before buying a new one, see if you can bend it back into shape.
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Old 07-23-09, 03:29 AM
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The cage can be manipulated with the instrument of your choice, *if needed*. Are you sure you're doing the adjustment correctly as per previous posts?
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Old 07-23-09, 07:59 AM
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Thanks for the help, folks.
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