Chainline/drivetrain issue and question. SOLVED!

[yetitotheheady]

Are the shift cables routed internally?

Ive seen cables unintentionally crisscrossed inside the frame. They can bind up against one another, hence the change in cable tension on the rear derailleur once you shift between the chainrings on the front.

[Clancy]

Originally Posted by oldpotatoe

Things I would check.

-Full der housing...no kinks, bends, smooth ends, ferrules? Might try 5mm housing and metal ferrules.

-Rear der cage alignment, pulley direction, cage not upside down.

-RH shifter..maybe something wonky inside?

-Chain length-maybe too short? Chain installed with 'shimano' facing outboard?

Been waiting/hoping for your reply.

Full cable housing, no kinks, sharp bends. And! I isolated the shift cable by disconnecting the cable clamp at the derailleur, pulling on the cable as I work the shifter to check smoothness and that the shifters is indexing properly - everything is good.

Chain is cut perfect. Done the same way I've done hundreds before.

The symptoms again...

It shifts perfectly in the small chainring, poorly in the large.

When in the large chainring it acts as if there's not enough cable tension, classic. Hesitates when shifting up, drops two cogs (more like 1 1/2) when shifting down. Classic systems of loose cable tension.

Adjust cable tension while in the large chainring, and now it shifts poorly when in the small chainring.

It's done this with the current and new 2x11 drivetrain, also with a 2x10 older drivetrain.

I know this next question is overly broad but how does one determine if the chainline is correct? If the chain is on the large chainring, which cog should it be on when the chain is parallel or in line with the bike? Exactly in the middle of the 5th cog or middle cog?

The frame is a Salsa Vaya Ti purchased new by me. I've contacted Salsa and they had no answers or suggestions. This was a few weeks ago when I had the 2x10 set-up. I emailed them two days ago asking what the recommended chainline is, have not heard back.

It's a spectacular frame, beautiful, and rides wonderfully. Shifts like crap.

I didn't want to state the frame because I didn't want to disparage it or cast it in a bad light. However I'm beginning to wonder if it is the problem. In the specs it states it's designed around a 68 BSA BB to be used either 1X or 2X. In their first reply, Salsa confirmed that the bike is designed around a 68mm BB.

However, by my eye, it looks as if the chainline would be better if the crank sat out further as it would with a 73mm BB. Unfortunately, that requires another crankset.

Money going down a rabbit hole.

[Clancy]

Originally Posted by yetitotheheady

Are the shift cables routed internally?

Ive seen cables unintentionally crisscrossed inside the frame. They can bind up against one another, hence the change in cable tension on the rear derailleur once you shift between the chainrings on the front.

All external housing and full housing.

Hard for me to see in my mind's eye how shifting into the large chainring would effect the cable tension on the rear derailleur if the rear derailleur housing is cut too short. Shifting up does reposition the rear derailleur throughout its entire range in effect pulling on the housing more. I've triple checked that but will again.

I like a big large loop going into the rear derailleur. I may install new and longer housing along with a new cable just to eliminate this as the problem. But I really don't believe it is. I've seen on full suspension MTB's where housing that's just a tad short will impact smoothness of shifting when the suspension is compressed. So you may be on to something.

I still suspect that the chainline is off.

[cmbicycles]

Post up some pictures of your setup, cable routing, etc... that way at least people can see what you/they are talking about.

[Pierre]

Are you supposed to be using a spacer in behind the cassette? If so, have you installed? Is the cassette nice and tight against the hub? I know, I'm reaching...

[Mark McM]

Bad chainlines can cause front shifting problems, and can cause noise and sometimes can cause chain jumping at the extremes of cross chaining, but it usually doesn't cause rear shifting problems (at least not the kind you are describing). Once the chain goes through the rear derailleur cage, it should become aligned properly with the cassette, and not cause shifting problems.

Offsets in rear shift indexing points between large and small chainrings is usually caused by rear derailleur alignment problems. The derailleur cage will extend and retract to take up different amounts of chain slack between large and small chainrings - if the derailleur is misaligned, the cage will move at an angle as it extends/retracts, resulting in different lateral alignments (and consequentially offsets in indexed positions).

You say that you have double checked the hanger alignment, but could the derailleur itself be twisted? Here's a quick check: Find the gear combination that results in the rear derailleur cage being in the most vertical alignment. Stand behind the bike, and eyeball the cassette and the derailleur cage. Is the derailleur cage lined up in the same vertical plane as the cassette sprockets? Another test is to observe the alignment between the engaged cassette sprocket and the derailleur top pulley while somebody else turns the cranks and shifts the front derailleur between chainrings. Do you see the derailleur top pulley move laterally when the shifting between chainrings?

[lzuk]

My wife's aluminum salsa had poor shifting. Did all the same checks. Finally found the weld on the dropout touched the mating surface of the derailleur. Filed it flat and good to go. Never heard back from Salsa as well

[-dustin]

Originally Posted by Clancy

When in the large chainring it acts as if there's not enough cable tension, classic. Hesitates when shifting up, drops two cogs (more like 1 1/2) when shifting down. Classic systems of loose cable tension.

this is the anomaly that rules out a number of potentials.

i'd say it's the chain or cassette, but given that both are new...who knows. too bad you don't have a sram chain laying around.

[cachagua]

Shift cables... can bind up against one another, hence the change in cable tension on the rear derailleur once you shift between the chainrings on the front...

Oooh, another really good idea. Definitely something to check. Forgot this completely when I was thinking about it before.

Although, would that make the r der shift like the cable was tighter, rather than looser?

[BikeNY]

Originally Posted by Mark McM

Bad chainlines can cause front shifting problems, and can cause noise and sometimes can cause chain jumping at the extremes of cross chaining, but it usually doesn't cause rear shifting problems (at least not the kind you are describing). Once the chain goes through the rear derailleur cage, it should become aligned properly with the cassette, and not cause shifting problems.

Offsets in rear shift indexing points between large and small chainrings is usually caused by rear derailleur alignment problems. The derailleur cage will extend and retract to take up different amounts of chain slack between large and small chainrings - if the derailleur is misaligned, the cage will move at an angle as it extends/retracts, resulting in different lateral alignments (and consequentially offsets in indexed positions).

You say that you have double checked the hanger alignment, but could the derailleur itself be twisted? Here's a quick check: Find the gear combination that results in the rear derailleur cage being in the most vertical alignment. Stand behind the bike, and eyeball the cassette and the derailleur cage. Is the derailleur cage lined up in the same vertical plane as the cassette sprockets? Another test is to observe the alignment between the engaged cassette sprocket and the derailleur top pulley while somebody else turns the cranks and shifts the front derailleur between chainrings. Do you see the derailleur top pulley move laterally when the shifting between chainrings?

This make the most sense to me. Get a new rear derailleur and give that a try. Or something funny on the derailleur hanger.

[-dustin]

you know, how old is this derailleur? is it new new, or new to you?

when sram derailleurs get some age, the little...ball joint?...that keeps the cage inline will wear. when the cage is rotated foward, it can shift out of place, which will cause the cage to kick like / <- that. small ring isn't a problem. it'll be noticed when you shift into the big ring. easy way to see it is to look at the derailleur from behind and see if a gap forms between the cage and the knuckle when in the big ring.

Pictured derailleur has many, many miles on it, but shows what I'm talking about.

[oldpotatoe]

Originally Posted by Clancy

Been waiting/hoping for your reply.

Full cable housing, no kinks, sharp bends. And! I isolated the shift cable by disconnecting the cable clamp at the derailleur, pulling on the cable as I work the shifter to check smoothness and that the shifters is indexing properly - everything is good.

Chain is cut perfect. Done the same way I've done hundreds before.

The symptoms again...

It shifts perfectly in the small chainring, poorly in the large.

When in the large chainring it acts as if there's not enough cable tension, classic. Hesitates when shifting up, drops two cogs (more like 1 1/2) when shifting down. Classic systems of loose cable tension.

Adjust cable tension while in the large chainring, and now it shifts poorly when in the small chainring.

It's done this with the current and new 2x11 drivetrain, also with a 2x10 older drivetrain.

I know this next question is overly broad but how does one determine if the chainline is correct? If the chain is on the large chainring, which cog should it be on when the chain is parallel or in line with the bike? Exactly in the middle of the 5th cog or middle cog?

The frame is a Salsa Vaya Ti purchased new by me. I've contacted Salsa and they had no answers or suggestions. This was a few weeks ago when I had the 2x10 set-up. I emailed them two days ago asking what the recommended chainline is, have not heard back.

It's a spectacular frame, beautiful, and rides wonderfully. Shifts like crap.

I didn't want to state the frame because I didn't want to disparage it or cast it in a bad light. However I'm beginning to wonder if it is the problem. In the specs it states it's designed around a 68 BSA BB to be used either 1X or 2X. In their first reply, Salsa confirmed that the bike is designed around a 68mm BB.

However, by my eye, it looks as if the chainline would be better if the crank sat out further as it would with a 73mm BB. Unfortunately, that requires another crankset.

Money going down a rabbit hole.

Regardless of some number, ‘proper’ chain line is when in middle of cogset, line between center of crank is parallel to top tube. So, middle of cogset, small ring small angle and middle of cogset, big ring, small angle. Unless it’s WAY out, it’s not chain line. Something is making cable draggy she going into big ring, which essentially ‘tightens’ the chain. I still think I’d try 5mm der housing and metal ferrules first(cheap also).

[dddd]

We've had a few real experts weigh in here, I believe cachagua nailed it early on, and I feel certain that the problem rests with the rear derailer cage somehow rotating off-axis from the rear axle.
I hadn't thought of the weld at the mounting surface, but I have had to correct many drivetrains that had off-axis (with the rear axle) derailer hangers and bent derailers, and all presented the described symptoms exactly, though not always in the same "direction" with respect to which chainring had which sort of problem.
Perhaps both of the derailers used here were bent. It is not an uncommon problem!
But I would also re-visit the derailer hanger's mounting bolt face being off-axis with the rear axle.
In the absence of alignment tools, ANY new and mounted long-cage rear derailer should provide a good enough indicator of whether the cage is running parallel to the cogs at various angular positions. I would install such derailer without cable, and then position the cage (by hand) vertically under the larger cogs of a clean cassette. Then I would sight down the parallelism between the large cogs and the cage (the pullies) from above.
I would then position the cage horizontally and repeat that, while viewing from behind the bike.
I have yet to come across a bike where an off-axis defect that was bad enough to be a problem did not show up with such a careful visual inspection.

Lastly, One can actually inspect a derailer's straightness while it is off of the bike simply by holding it in front of the horizon while sighting off of the end of the mounting bolt! I have used this to reject many used-derailer purchases in the field, and have come to trust my eye to the degree that I feel that any significant misalignment between cage and mounting bolt is clearly visible. Here again, one should look from at least two angles by rotating the cage about it's pivot.

[Clancy]

Originally Posted by Mark McM

You say that you have double checked the hanger alignment, but could the derailleur itself be twisted? Here's a quick check: Find the gear combination that results in the rear derailleur cage being in the most vertical alignment. Stand behind the bike, and eyeball the cassette and the derailleur cage. Is the derailleur cage lined up in the same vertical plane as the cassette sprockets? Another test is to observe the alignment between the engaged cassette sprocket and the derailleur top pulley while somebody else turns the cranks and shifts the front derailleur between chainrings. Do you see the derailleur top pulley move laterally when the shifting between chainrings?

Last night I replaced the cable and housing just to make sure that the problem isn't caused by the cable housing being cut too short and causing increased tension when shifting up to the large chainring.

Problem remained.

With the bike in the stand I then had my wife pedal and shift as I observed the guide pully's alignment. And sure enough, the guide pulley moves ever so slightly inboard every time.

Reminder, the bike uses full cable housing.

The current set-up uses a new Rival 1 rear derailleur, new Rival 22 Hydro shifters, new SRAM Red 11-32 cassette, new Shimano chain.

The derailleur is a Rival 1 obviously intended for a 1X set-up. I assumed it wouldn't matter if it's used in a 2X set-up - I thought what does the rear derailleur care what's happening up front?

Is the Rival 1 derailleur the issue?

Because! Here's the other piece, the bike was doing the exact thing when I first built it up using SRAM Force 2x10 shifters and a SRAM X-9 rear derailleur. Exact same symptoms.

Where the Rival 1 is designed for a 1X set-up, the X-9 is designed for a 2X and the cable pull ratio is correct to use with Force shifters.

And, I had installed that groupset on a Gunnar Hyper-X and the shifting on that bike was perfect. When I purchased the Salsa Vaya Ti, I transferred the groupset from the Gunnar to the Salsa and the problems began.

So now I believe it's a soft derailleur hanger. The hanger is the stock one that came on the bike. I'm going to order a replacement from Wheels Manufacturing, not Salsa.

I also ordered a Rival mid cage derailleur to eliminate the Rival 1 as the issue.

Common that a derailleur hanger is not stiff enough?

Money down a rabbit hole

[oldpotatoe]

Originally Posted by Clancy

Last night I replaced the cable and housing just to make sure that the problem isn't caused by the cable housing being cut too short and causing increased tension when shifting up to the large chainring.

Problem remained.

With the bike in the stand I then had my wife pedal and shift as I observed the guide pully's alignment. And sure enough, the guide pulley moves ever so slightly inboard every time.

Reminder, the bike uses full cable housing.

The current set-up uses a new Rival 1 rear derailleur, new Rival 22 Hydro shifters, new SRAM Red 11-32 cassette, new Shimano chain.

The derailleur is a Rival 1 obviously intended for a 1X set-up. I assumed it wouldn't matter if it's used in a 2X set-up - I thought what does the rear derailleur care what's happening up front?

Is the Rival 1 derailleur the issue?

Because! Here's the other piece, the bike was doing the exact thing when I first built it up using SRAM Force 2x10 shifters and a SRAM X-9 rear derailleur. Exact same symptoms.

Where the Rival 1 is designed for a 1X set-up, the X-9 is designed for a 2X and the cable pull ratio is correct to use with Force shifters.

And, I had installed that groupset on a Gunnar Hyper-X and the shifting on that bike was perfect. When I purchased the Salsa Vaya Ti, I transferred the groupset from the Gunnar to the Salsa and the problems began.

So now I believe it's a soft derailleur hanger. The hanger is the stock one that came on the bike. I'm going to order a replacement from Wheels Manufacturing, not Salsa.

I also ordered a Rival mid cage derailleur to eliminate the Rival 1 as the issue.

Common that a derailleur hanger is not stiff enough?

Money down a rabbit hole

Yes...and a new rear der can't hurt...Good luck. Hope it works.