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Discussion Starter · #1 ·
I have a Sette Ace frame I am building up. Which has a 73mm bottom bracket width. I am installing a Shimano M582 crankset which supposedly calls for one spacer on the drive side of 2.5mm.

I cannot get the cage closer to the chain on the smaller cog, the low adjustment screw is all the way tight. The gap just seems too big. The cage is lined up straight as I can get it. The cable is not installed yet.

I also set the chain on the big ring on the back and small ring on the front and noticed my chain is pretty out of line. Is this normal from what you see in the pictures? Could this be the cause for me not being able to set the front derailleur properly? Can I remove that spacer and put it on the left side?
 

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I noticed that as well while building my ace, where for a 73mm shell, you would normally include one spacer on the drive side. I removed that spacer and am running the BB without any spacers.
 

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Neu5p3ed said:
I cannot get the cage closer to the chain on the smaller cog, the low adjustment screw is all the way tight. The gap just seems too big.
Do you mean the gap between the chain and the inside of the front derailleur cage? You should definitely install the cable before you start fine tuning.

As far as chainline, I thought you should be shooting for straight while in the middle ring and somewhere in the middle of the cassette. Chainring assembly is narrower than cassette, so there is no way for chain to be straight through every gear combo.
 

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Discussion Starter · #4 ·
drmayer said:
I noticed that as well while building my ace, where for a 73mm shell, you would normally include one spacer on the drive side. I removed that spacer and am running the BB without any spacers.
I might have to try this, but was wondering if any problems can arise from doing so?
 

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Discussion Starter · #5 ·
cackalacky said:
Do you mean the gap between the chain and the inside of the front derailleur cage? You should definitely install the cable before you start fine tuning.

As far as chainline, I thought you should be shooting for straight while in the middle ring and somewhere in the middle of the cassette. Chainring assembly is narrower than cassette, so there is no way for chain to be straight through every gear combo.
You are correct, I am referring to the gap.

From the instructions I've gathered, is to adjust the gap with the low limit screw, while the cable is loose and the chain on the small ring up front and big ring on the back. Then after that is done adjust the high limit screw while the chain is on the big ring up front and the small ring in the back.

I probably misunderstood and should have worded it differently. I still can't adjust any further the low limit screw and whenever I shift to the small ring the chain drops, due to the too big of the gap.:madman:
 

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~Disc~Golf~
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ace has a 73 mm BB?? why?
My Flite is still 68mm - weird

(sorry I have nothing constructive :()
 

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Discussion Starter · #7 ·
I can't for the life of me adjust the front derailleur cage any further to prevent it from dropping the chain onto the bottom bracket. I need to lessen the gap to prevent this and the only way I can see doing so is removing the spacer.

My previous frame I built had a 68mm bb, but I had a different front derailleur, but should be the same concept with this Shimano XT front derailleur. So i'm sure it isn't something i'm doing totally wrong.
 

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I could be wrong, but it looks like the derailleur might be making contact with the drive-side pivot......

Also I would think that removing the drive-side spacer would make the chain-line worse, not better....

Any chance you could just throw the front derailleur in the trash and go 1 X 9 ???????
 

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Discussion Starter · #9 ·
Derailleur is not making contact.

Sorry no 1x9, lol.

I'm going to try and see what happens tomorrow when I remove the spacer on the right side. Since "drmayer" who replied above, was able to due so apparently without issues.

You can also see that the previous owner of the frame was dropping the chain as well, by looking at the marks on the BB. He probably had similar issues.
 

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Fat-tired Roadie
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Sorry, joining the party late...

It sounds like you bought a mail-order bike used, from someone who couldn't get it set up right either.

There's currently no cable operating the front derailleur and you're concerned because you think that the chain will drop off the small ring if you shift all the way down. You've also noticed that geared bikes don't have perfect chainline. I get a little confused here.

Is your low limit screw on the front derailleur already screwed in all the way? In the pictures, it looks like your derailleur is actually resting against your seat tube, which would mean the low limit screw isn't doing anything. Can you photograph the limit screws?

The limit screws are a standard Metric size, so if you just need a longer low screw, you can get one at a hardware store. I'm surprised that it seems necessary, though.

As far as removing a spacer goes - the crankset is designed to go in a bottom bracket with the inboard faces a certain distance apart. All the configurations in the manual put them at that distance. There's certainly some wiggle room, since bottom brackets, spacers and the clamps for E-type front derailleurs are not always their nominal width. However, I'd be worried about bottoming out the left crank arm before getting proper preload on the bearing. Not saying you shouldn't do it - just saying you should be aware of the potential problem. You'll also end up with your right-hand pedal 2.5mm closer to the centerline of the bike than your left. That's not much, but I have a similar misalignment on an older bike I commute on, and it is noticeable.

Is your front derailleur cage parallel with the centerline of the bike and your chain rings? Can you photograph that from above?

What if you measure your bottom bracket shell? How wide is it really?
 

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AndrwSwitch said:
Is your low limit screw on the front derailleur already screwed in all the way? In the pictures, it looks like your derailleur is actually resting against your seat tube, which would mean the low limit screw isn't doing anything. Can you photograph the limit screws?
This sounds right. Maybe a longer screw is in order. I don't think I'd remove the BB spacer unless you are convinced it will help your chainline and not cause any crank/frame interference.
 

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Discussion Starter · #12 ·
AndrwSwitch said:
Sorry, joining the party late...

It sounds like you bought a mail-order bike used, from someone who couldn't get it set up right either.

There's currently no cable operating the front derailleur and you're concerned because you think that the chain will drop off the small ring if you shift all the way down. You've also noticed that geared bikes don't have perfect chainline. I get a little confused here.

Is your low limit screw on the front derailleur already screwed in all the way? In the pictures, it looks like your derailleur is actually resting against your seat tube, which would mean the low limit screw isn't doing anything. Can you photograph the limit screws?

The limit screws are a standard Metric size, so if you just need a longer low screw, you can get one at a hardware store. I'm surprised that it seems necessary, though.

As far as removing a spacer goes - the crankset is designed to go in a bottom bracket with the inboard faces a certain distance apart. All the configurations in the manual put them at that distance. There's certainly some wiggle room, since bottom brackets, spacers and the clamps for E-type front derailleurs are not always their nominal width. However, I'd be worried about bottoming out the left crank arm before getting proper preload on the bearing. Not saying you shouldn't do it - just saying you should be aware of the potential problem. You'll also end up with your right-hand pedal 2.5mm closer to the centerline of the bike than your left. That's not much, but I have a similar misalignment on an older bike I commute on, and it is noticeable.

Is your front derailleur cage parallel with the centerline of the bike and your chain rings? Can you photograph that from above?

What if you measure your bottom bracket shell? How wide is it really?
Currently my lo-limit screw is tightened all the way in. The bikes bottom bracket width from what I measured is spot on 73mm wide. How wide is it really (are you referring to the width with the bottom bracket installed?).
 

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Fat-tired Roadie
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Weird problem. I'd be inclined to get the longer screw before changing the spacer configuration. But as I mention above, I'm sensitive to funny little misalignments in my crankset.

The seat tube's not off-center is it? I know a few Fishers are designed that way, but looking at pics of the Ace elsewhere on the 'net, it looks pretty symmetrical.

Some other things that might cause this, although I think they're long-shots... You have the road instead of mountain bottom bracket (should be labeled on the housing.) The crank is not seated properly in the bottom bracket.

The first one seems somewhat possible - the bottom brackets are partially compatible. The second one... less so. I found installing the HT II crank I have to be pretty simple.
 

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Discussion Starter · #14 ·
AndrwSwitch said:
Weird problem. I'd be inclined to get the longer screw before changing the spacer configuration. But as I mention above, I'm sensitive to funny little misalignments in my crankset.

The seat tube's not off-center is it? I know a few Fishers are designed that way, but looking at pics of the Ace elsewhere on the 'net, it looks pretty symmetrical.

Some other things that might cause this, although I think they're long-shots... You have the road instead of mountain bottom bracket (should be labeled on the housing.) The crank is not seated properly in the bottom bracket.

The first one seems somewhat possible - the bottom brackets are partially compatible. The second one... less so. I found installing the HT II crank I have to be pretty simple.
From what I see the seat tube is pretty much in the center. The bottom bracket/crank was used previously on my other frame so I know for sure its not for a road bike.

I will try to see if getting a longer screw will help. Hopefully this can fix it.
 

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Chain line is massively off...

Look at the wear on the big ring.

Set up BB so that when in granny granny the chain is straight, or in big big the chain is straight...

Or at least as far as you can get it.
 

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Discussion Starter · #16 ·
jeffscott said:
Chain line is massively off...

Look at the wear on the big ring.

Set up BB so that when in granny granny the chain is straight, or in big big the chain is straight...

Or at least as far as you can get it.
The crank is from my previous frame (swapped), the derailleur in this case came with this frame from previous user.

So i'm getting conflicting answers in the above post person states that the chain should be straight while in the middle ring on the back and middle ring up front. Your mentioning it should be straight in the granny gear up front and big ring on the back? And big gear up front and small ring in the back?
 

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You prob. already did this, but make sure the crank is properly torqued down. If its just "snugged up" that will cause a problem, of course.

I say this because the last one I installed I thought was pretty tight, but went to double check and it needed a little more torque, which moved the crank inward quite a bit.
 

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Neu5p3ed said:
So i'm getting conflicting answers in the above post person states that the chain should be straight while in the middle ring on the back and middle ring up front. Your mentioning it should be straight in the granny gear up front and big ring on the back? And big gear up front and small ring in the back?
Check out:
http://www.sheldonbrown.com/chainline.html
 

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Discussion Starter · #19 ·
I think I've found an answer, from another forum. I measured my rear and it is 135mm which should have a 47.5 chainline. I measured and my chainline is currently at 50. If I remove the spacer on the right it should bring it down to 47.5 inline with the rear.

Another question is do I have to move the spacer to the left side if I remove it from the right side bottom bracket?

From other forum:

Chainline is defined as the distance from the centerline of your bike to the centerline of your gears..ie middle ring on a three ring crank...middle cog in the cassette, etc.
Generally the rear end determines the chainline and there are essentially two MTB standards.
135 rear = 47.5mm
150 rear = 55mm
Now there are the odd frames like all the demos (and others) that have 135 rear ends with 150 chainline and you IH that had a 150 rear with 135 chainline (because of floating brake).

Within the same bb shell width catagory, yes to an extent. SO lets say a set of XT cranks (only avail for 68/73 mm bb) or 68/73mm saints have a nominal 50mm chainline when set up as suggested by shimano (it should also be noted that 50 is NOT the correct chainline for a frame with a 135mm rear end....47.5 is. The extra width came about with external bbs). If desired, you can move spacers from drive to non-drive side (or vice versa) to change the chainline by the spacer thickness (2.5 mm as supplied).
 

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Discussion Starter · #20 ·
Good news, looks like the problem has been fixed by removing the spacer on the right side. Also read a suggestion from another forum that if I am running a 135 rear and have a 73 front to just run the 73 bottom bracket, and it appears to have fixed my issues. I just have to fine tune things now, hopefully I won't run into anymore issues.
 
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