inner chainring big sprocket noise -- chainline? new chain?

[jasong]

Hi, I have a new road bike with Ultegra front rings, Tiagra 9 spd cassette, and HG53 chain. The front derailleur is not touching the chain, but there is an audible noise when in the largest sprocket and the next to largest. Looking down onto the front inner chainring, it does appear that the chain is being bent significantly and this is making the noise.

Will this noise go away? I am using Pedros Dry lubricant and everything is quite clean. The bike only has 40 miles on it.

I am pretty sure it's not the rear derailleur B adjustment, as rotating the rear body in a vertical plane (simulating B adj) doesn't reduce the noise.

I searched for other similar posts and found one person that had similar issues, but am curious about some compatibility issues.

Is Tiagra cassette ok with the Ultegra front rings (probably)? Is the HG53 chain ok with the Ultegra front rings? The Shimano tech document CS_6500_SI.pdf (9-Speed Cassette Sprockets - CS-6500) says

"
Do not use the CS-6500 in any combination other than with the
CN-HG92, CN-7700. Other chains cannot be used as the sizes do
not match.
"

Any thoughts? The rear wheel is an ALX-300, but I have also put a 9speed Mavic Cosmo in the back and heard the same thing.

Does the Ultegra HG92/HG93 chain bend better than the Tiagra HG53? Would another lubricant be better (I read somewhere else they were saying stay really wet for this)? And should I break in this chain (if that's the solution) by trying to stay out of these gear combinations?

 

[GuyStevens]

When in the small chainring/big sprocket combination your chain should be straight. If not, this points to the bottom bracket axle being too wide. Are you running double or triple chainrings?

 

[Cipher]

Originally posted by GuyStevens
When in the small chainring/big sprocket combination your chain should be straight. If not, this points to the bottom bracket axle being too wide. Are you running double or triple chainrings?

Mine is not straight with that combination... (Record 2x10 w/a Record 102mm bottom bracket). Typically you are not 'straight' until you are in the 3rd or 4th cog and 39 front. (I'd take a little closer look).

 

[Gonzo Bob]

The noise you are hearing may be completely normal. The chain is only straight or nearly straight in a few gear combinations in the middle of the cassette. When you use the largest or smallest cogs, there is always chain deflection and the largest cogs almost always run a little noiser because of the higher chain tension.

However, the noise could also be caused by a misaligned rear derailer. This could show up only on the larger cogs due to the higher chain tension. A way to check this is to put the bike somewhere where you can turn the cranks and have the rear wheel spin freely. I use my indoor trainer. Shift to the the "problem" gear and spin the cranks and very slightly push in on the body of the rear derailer. If the drivetrain quiets down when you do this, you need to increase the shifter cable tension by turning the barrel adjuster counter clockwise. If the drivetrain quiets down when you pull out on the body of the rear derailer, you need to decrease cable tension by turning the barrel adjust clockwise.

 

[boudreaux]

Originally posted by GuyStevens
When in the small chainring/big sprocket combination your chain should be straight. If not, this points to the bottom bracket axle being too wide. Are you running double or triple chainrings?

That's hooey

 

[boudreaux]

Originally posted by jasong


"
Do not use the CS-6500 in any combination other than with the
CN-HG92, CN-7700. Other chains cannot be used as the sizes do
not match.
"

That is shimano hooey.What crank/BB/spindle length are you using?

 

[dhk]

Believe your noise will decrease with more break-in miles and a more/wetter chain lube, as you mentioned. But, I don't like using the big ring/big cog combination for these reasons:

1) Forces the chain to bend sideways, contributing to more friction and faster wear; 2) Chain runs at it's highest tension, so more friction loss than necessary; 3) Chain runs at an angle to the rear axle, rather than square, so you've got added loss of torque due the geometry.

 

[boudreaux]

Originally posted by dhk
Believe your noise will decrease with more break-in miles and a more/wetter chain lube, as you mentioned. But, I don't like using the big ring/big cog combination for these reasons:

He is using the small ring big cog. Perfectly normal combination.

 

[dhk]

Yes, I need to read more carefully before jumping....the term "largest sprocket" threw me off.

 

[daveornee]

<SNIP>
Your words:
"Looking down onto the front inner chainring, it does appear that the chain is being bent significantly and this is making the noise."

from what you said.................................

I would say that you should check your chainline and Rear Derailer alignment.

 

[jasong]

Without sounding too foolish, how do I find the values for the spindle/BB/crankarms without relying on my own measurements?

BTW, this is a double chainring and 9 speed cassette. Tiagra in back, ultegra in front. Ultegra STIs.

Also, how do I check the chainline exactly? The cassette has no more room to shift stuff toward right (away from hub) to reduce the angle. And it doesn't appear as though the BB has much width reduction to make the chainline less fierce from that angle.

Thanks for your help guys,

 

[jasong]

Gonzo Bob, I don't think the rear derailleur is contributing to the noise. I did push in a little and pull in a little (laterally) and it only increases the noise. I have smooth shifting in the back and have been paying close attention to make sure the derailleurs aren't touching. I also fore/aft pushed on the rear derailleur simulating B adjust but that doesn't do anything either.

I'm fairly convinced that the chain line is fairly extreme from the small ring to big cog, my concern is just whether or not this is acceptable and if I should stay away from this combination during this breakin.

I may just keep this thing on the trainer for a while until I get a few hundred miles.

Is there a tolerance that is given for acceptable chainline for a given chain? I guess I could measure the angle that's formed between the top of the ring and top of the cog, and see if that's within it? What do you guys do in a shop if it's in doubt whether or not a given combination will work? Or if frame is out of alignment?

Thanks for help, any more ideas?

 

[boudreaux]

Originally posted by jasong
Gonzo Bob, I don't think the rear derailleur is contributing to the noise. I did push in a little and pull in a little (laterally) and it only increases the noise. I have smooth shifting in the back and have been paying close attention to make sure the derailleurs aren't touching. I also fore/aft pushed on the rear derailleur simulating B adjust but that doesn't do anything either.

I'm fairly convinced that the chain line is fairly extreme from the small ring to big cog, my concern is just whether or not this is acceptable and if I should stay away from this combination during this breakin.

I may just keep this thing on the trainer for a while until I get a few hundred miles.

Is there a tolerance that is given for acceptable chainline for a given chain? I guess I could measure the angle that's formed between the top of the ring and top of the cog, and see if that's within it? What do you guys do in a shop if it's in doubt whether or not a given combination will work? Or if frame is out of alignment?

Thanks for help, any more ideas?

You never did answer the question of what crank/BB and spindle length. If this setup came from a factory it's probably safe to asssume everything is correct.If you cobbed it together,it's probably safe to assume you got a mismatch.The combination should be perfectly usable.It it shifts right,derailer adjustment is correct. There could be defective cogs.or you just need to give it some more time.

 

[daveornee]

Originally posted by jasong
Gonzo Bob, I don't think the rear derailleur is contributing to the noise. I did push in a little and pull in a little (laterally) and it only increases the noise. I have smooth shifting in the back and have been paying close attention to make sure the derailleurs aren't touching. I also fore/aft pushed on the rear derailleur simulating B adjust but that doesn't do anything either.

I'm fairly convinced that the chain line is fairly extreme from the small ring to big cog, my concern is just whether or not this is acceptable and if I should stay away from this combination during this breakin.

I may just keep this thing on the trainer for a while until I get a few hundred miles.

Is there a tolerance that is given for acceptable chainline for a given chain? I guess I could measure the angle that's formed between the top of the ring and top of the cog, and see if that's within it? What do you guys do in a shop if it's in doubt whether or not a given combination will work? Or if frame is out of alignment?

Thanks for help, any more ideas?

Take a look at the Park Tool site:
http://www.parktool.com/repair_help/clg2.shtml

Something about your component combination makes me wonder if someone didin't put the Ultegra crank on this bicycle after delivery. It could be that the bottom bracket isn't the correct length (too long) for this crank, or even worse, that the crank wasn't properly mounted.
I wouldn't ride it any more until you get this checked out by a shop.

 

[Calvin Jones]

It is possible the front chainwheels are too far from the bike center line. As the chain wears and rounds the teeth, the noise should quite down a bit. If chainline is the issue, try shifting outward in the rear one cog at a time and see if it quites down, which it will likely do.

You might try to measure the front ring chainline and see if it meets the spec for that model. Also, compare it to the rear.

See http://www.parktool.com/repair_help/clg2.shtml
You do not need the CLG-2 to do the above measurements.

 

[jasong]

Thanks for the replies Calvin, Dave,Boudreaux. Thanks for the links on the chainline tool. I will play with that some.

The bike is a complete bike, I didn't piece stuff together so in theory no noise. Cranks are 172.5 mm. Frame is 57cm C-C.

Still don't know BB or spindle vals.

 

[jasong]

Originally posted by jasong
Thanks for the replies Calvin, Dave,Boudreaux. Thanks for the links on the chainline tool. I will play with that some.

The bike is a complete bike, I didn't piece stuff together so in theory no noise. Cranks are 172.5 mm. Frame is 57cm C-C.

Still don't know BB or spindle vals.

The BB is 68 x 109.5, it's a 9 speed shimano tiagra cassette, ultegra 53x39 front, crank length 172.5 mm. 57cm frame.

Thanks for help guys,