Chain line problem

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miltmaster3
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by miltmaster3

Frame : s works sl5. bottom :bb30 . crank : rotor 3d+ 30mm. group set : dura ace 9000. spider : power2max .chainset: rotor non q 130bcd 53-39 . problem: when I have 39 -11 the chain touch the 53 chainring make the chain jump! the front derailleur is correct is it normal? The chain line is 43.5

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Last edited by miltmaster3 on Fri Dec 02, 2016 1:41 pm, edited 4 times in total.
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Marin
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by Marin

That's normal with non-standard setups. Solution: Never use small/small. Unlike big/big there is no reason to use it.

by Weenie


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bikerjulio
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by bikerjulio

There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

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miltmaster3
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by miltmaster3

Thanks you all

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Rick
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by Rick

Just for the record:
Yeah, we all know you shouldn't use the extreme cross chain positions. But I have been doing it all the time for decades with no apparent negative effects.
In the small-small combo, you run the risk of having the chain rub against the big chainring. I have had that occasionally, but solved it by adjusting the derailleur hanger. The derailleur should be "straight" using an alignment tool, but all specifications have a tolerance, and I just set mine so that it is "in" slightly and "pointed" toward the little chainring (pointing in toward the front).

I am staying "within tolerances" so my hanger is still "aligned properly". I can't remember the spec, but I think it is like +/- 2mm when the derailleur adjustment rod is measuring to the wheel's rim ?
Chainstay length will also affect this, with shorter chainstays causing more problems; and chainring design will also create differences. I was unable to get WickWerx chainrings to operate at all in the X-chain position because they are a bit thicker and have thicker molded-in ramps. (Even though they were otherwise very nice and quick-shifting rings!)

Of course everything has to be adjusted CAREFULLY in every scenario. :)

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kgt
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by kgt

Maybe Rotor chainrings are thicker as well.

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miltmaster3
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by miltmaster3

My derailleur has nothing to do I have lot of space between derailleur and chain

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Valbrona
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by Valbrona

How well is your crankset centred?

If chainsatys are symmetric, measure gap between tip of each crank arm and chainstay. Use spacers to adjust position of axle/chainline. That is what spacers are for.

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miltmaster3
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by miltmaster3

Chain line is OK 43.5. I put 3 spacers but nothing

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mattr
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by mattr

Marin wrote:That's normal with non-standard setups.
It's normal with standard set ups.
I've had it on 7, 8, 9, 10 and now 11.

It seemed to be slightly be better on campag and the new shimano 11 seems better than the outgoing 10.

Either don't use those ratios. Get a different cassette to change the angle the chain comes in at. (Bigger is better) or a smaller step between chainrings (42/53)

Don't muck around twisting hangers.

FWIW most bikes used to have chainstay length that was very close or under to shimanos minimum requirement. Which makes the problem worse.
Don't know what the current standard is though.

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jekyll man
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by jekyll man

Change your back wheel to one where the cassette sits a little more inboard?
Official cafe stop tester

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miltmaster3
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by miltmaster3

Rotor knows the problem there is noting I Can do I will always lose 1 or 2 speed in 39 disk. The have the problem with s works sl4 (not with rubeux) I have 2 option 1 keep it 2 get s works crank arm's

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mattr
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by mattr

Sworks cranks are unlikely to fix the issue either.

You either have to have the rings far enough apart that the chain doesn't rub, at which point they won't shift either. Or push the chain line so far out that you can't use half the cassette on the big ring.

You don't have the issue on the Roubaix as I suspect the chainstays are longer.

mattr
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by mattr

Just checked, roubaix stays are between 7 and 10mm longer, so it will tend towards rubbing less, as the angle between chain and chainrings will be *very* slightly better.

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miltmaster3
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by miltmaster3

That was rotor answer when I email them about my problem

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