PeteDman

I just upgraded most of my drive train and everything went on smooth. I'm noticing that when I pedal im getting a lot of vibration coming from the drive train. When I have the bike up on the work stand and I pedal, I can feel the vibration and you can see the chain vibrating in an up and down manner (hope that makes sense).

Things I have done to try to trouble shoot;
Removed the rear cassette to make sure the cogs where facing in the right direction. Cassette is straight with NO wobble.
Adjusted rear derailleur cable and barrel adjuster
Took chain off the crankset and pedaled and its smooth as silk


I just replaced the following:

Rear cassette from 9 speed 12-25 to 10 speed 12-25
Front derailleur from Tiagra triple to 105 double
Chain from 9 speed to Ultegra 10 speed
Crankset from Truvantiv triple to Sram Rival double

What could be causing his vibration?

Thanks

Unkle Rico

The only thing that comes to mind is that your chain might be to long or the cassette lock ring might not be on tight enough? Where are you seeing this "up and down" motion on the chain?

RoadGuy

10-speed chain is thinned and more flexible. Even if you got the chain length correct, I think it would be more prone to vibration.

Length length may be longer than necessary, allowing the chain to bounce or vibrate.

Rear derailleur may not be taking up the chain slack (spring may be too soft by design or manufacturing defect). B-screw not adjusted properly? Rear derailleur not adjusted properly

PeteDman

Yes the up and down is on the chain. Here's how I determined the chain length.
Put the chain on the small ring and on the small cog. I pulled it together until the chain was not touching the bottom of the derailleur by about 1/2 inch, then I put in the pin. Should I go shorter?

JerrySTL

Shimano 10-speed chains are supposed to be installed with the correct inside and outside orientation. You should be able to see the chain model number on the links from the outside if properly installed.

dsbrantjr

Before you go further, GENTLY shift into the big chain ring/big cog combination while turning the cranks by hand; the chain should be long enough to shift into that combination without straining anything and there should be some slack left on chain.

If not DO NOT ride the bike until you have made the chain long enough. If it is too short and you forgetfully shift (and you will eventually) into that combination you can do severe damage to the mechanism or even the bike frame. Then continue troubleshooting

You should then check that the cassette overhangs the hub a a couple of millimeters so that the lock ring is clamping the cassette and not bottoming out on the hub instead. You may need a thicker/additional spacer behind the cassette if there is not sufficient overhang. You should not be able to move the cassette relative to the hub when the lock ring is torqued properly. There may be some slight eccentricity of the cassette but not more that a millimeter or so.

fietsbob

I cant see whats not in front of me.. so ..

<Just a Guess> upper guide pulley sitting right on top of the low gear cog.

Shimagnolo

Is it the lower portion of the chain that is vibrating?
This sounds like what happens when you put a new chain on a wornout chainring.
The worn chainring will have slightly-hooked teeth that will attempt to hold the chain, but the RD spring tension tugs the chain off of the teeth. This is called "chain suck". If it is a really bad case, the chain will be held against the chainring and jammed into the underside of the FD.

dsbrantjr

Also make sure that the chain is correctly threaded through the derailleur, if it's wrong it can ride along the tab that many of them have; I've made this mistake myself. It kind-of-works but makes a noise/vibration.

dsbrantjr

OP states new chain and cassette.

PeteDman

Thanks for the tips guys. Since everything is installed correctly I decided to run over to my LBS for them to take a look at it and I was given the thumbs up. Everything is working properly and they say that the chain needs a few miles on it but it will settle in and get better.

Thanks again

Shimagnolo

Exactly.
A new chain + old chainring can result in chain suck.

FBinNY 

IMO, we need to separate some issues. There's vibration, which I take to mean fast cycles fo small movements that may be barely visible, but can be felt or heard as a hum or buzz. And there's up and down movement, which if beyond what would be classed as vibration would be slower changes in visible chain height, with changes greater than 1-2mm total.

Then you need to isolate when you get the vibration, or issues. All the time, only in select gear combos, only under load? Do you see the idler cage slowly rock back and forth? Is there any kind of steady sawing or buzzing sound? If so, is it all the time? Does the bike backpedal smoothly, or at least as smoothly as forward?

All of those are important clues, just as when you go to a doctor, he'll want better descriptions of your illness, fever? how high? chills? muscle pain, stomach or headache, etc.

Different things cause different effects. For example one of the most common causes of serious vibration and noise when a chain is replaced is threading it wrong so it rubs on the safety tab in the middle of the RD cage. A tip off that this is what you did, is if it snags when backpedaling. But I know of someone not attuned who rode hundreds of miles this way before someone commented about it.

So, con sider this my pitch for more info, and maybe I'll be able to give you a fix, or assure you that you're within the bounds of normal new chain/sprocket noise, and it'll improve somewhat over the next 100 miles.

HillRider

Some Shimano 10-speed chains are directional and some are not. CN-5600 and CN-6600 are not. CN5700 and CN6700 are directional.

PeteDman

It's a constant buzz. More noticeable when in the big ring and smallest cog but that could be that it takes more force and therefore its giving me more feedback. Back pedaling is smooth with no buzz. To be clear the chain moving up and down is actually the vibration causing the issue.

I have been cranking it quite a bit and seems to be getting better or im just getting used to it. The guy at LBS said everything looked good to him. I guess only time will tell.

FBinNY 

OK, so it's a straight out vibration. Here's two things to consider.

1- chordal action -- basically chains and sprockets are different than ropes on pulleys. We think of sprockets as being round, but actually they're polygons with the number of sides equal to he number of teeth. Imagine your front wheel as being a 100 sided disc, now 50 sides, now20, now 11. The fewer sides the rougher the ride, or the more vibration. Same with your chain. Read more if interested.

2- side vibration -- your chain has inner and outer links. Straight on it doesn't matter because the plates don't touch anything. But when the chain leaves the sprocket a an angle, such as when on the outermost ones, the plate rubs down the side of the top tooth until it clears. That allows the chain to move over a bit, until the next inner plate is rubbing the tooth passing 12 o'clock.

So you have two unavoidable sources of vibration. The side vibration will quiet some as the sides of the tips of the teeth wear in a bit, but chordal action is here to stay.

Another source of vibration are worn pulleys. They shrink with wear, so the chain's pitch is too great for the teeth and the chain is constantly shifting around as it runs. If the buzz bothers you consider replacing at least the lower pulley with a new plastic one, which should run quieter.

Lastly, and consider the source here, chain lube can make a big difference here. It doesn't magically change anything, but some lubes, which I won't name, are designed to cushion all those tiny shocks, and muffle the noise. If you're running a light lube of any kind, and the noise bothers you, consider a change.