Break in Period for Noisy Drive Train?
 

I have a new bike with a Shimano Deore drive train and it's noisy. I've adjusted it as per the infinite wisdom of youtube and I'm pretty sure it's working as it should - clean shifts etc. The chain is sitting squarely in the middle of each gear. Although it came with some oil on it, I've lubed it up with Finish Line Dry Teflon. Yet, when I pedal it seems to make a lot of mechanical noise. There also seems to be a bit of a pattern to the noise. The bike has under 10 km on it - should I just give it some time to break in? Or could something be defective?

new bike? bring it back to the shop tell them to do it right

It came in a box, I put it together myself. I probably should pay someone $40 to "tune" it up. But I do all my own mechanics on my vehicles and motorcycles and I feel quite comfortable turning wrenches. Perhaps I'm giving myself too much credit, but I'm pretty sure I can adjust a bike as well as they can for $40.

I may have adjusted something wrong, but the chain moves smoothly, does not bind etc, shifting is good, etc. It just seems to be a little clicky. The chain is sitting squarely on the center of each gear - we're not talking about noise due to the derailer being out of adjustment.

is the RD top pulley hitting the cassette?

Are you sure the chain is running over "only" sprockets and idlers? Is the side of the chain touching any part of the derailleurs frames. Is the chain running straight and true. Are the derailleurs running straight and true, in perfect symetry with the sprockets.

Bike mechanics are pretty straight forward.

Tooth to tooth there's about a 1/4 inch clearance.

I have seen brand new chains and cassettes run noisy together. 10 km is a very short distance so it's still possible that the noise will go away after another 10-20 km.

Yep, the upper pulley (jockey wheel?) has a slight wobble to it - which coincides with the pattern of sound. It's probably wobbling 1/16" of an inch I'd guess but evidently it's enough to make noise. Is this something to be concerned about - or something that I should complain about on a brand new bike? Maybe I can get a new part under warranty? I'd exchange it but they're sold out and I kinda like the bike.

That play is supposed to be there on the upper jockey wheel. It helps the chain run smoother at higher chain angles.

Check your chain for tight links though. They should all pivot freely. If not, work them around until they do and that should clear up the noise.

By pivot - do you mean the chain should have some flex in it laterally - I'm thinking maybe it's a little tight in some sections and this is causing the jockey wheel to wobble (rather than the other way around) ?

An obvious once per rev source of noise is the front derrailleur cage being rubbed by the chain. Where it's safe look down while pedalling to see if your chain is scuffing on the side of the FD cage. Adjust as required either by trimming the barrel ajuster at the shifter or correctly aligning the FD on the frame according to specs found at www.parktool.com/repair .

Are you sure that the chain is not running over a crossmember on the rear derailleur. It should contact nothing but jockey wheels.

The chain should pivot freely - it should not bind anywhere. Stress it sideways a little, if it binds.

A Deore drivetrain, should run as quiet as a church mouse.

...but what is the pattern? If it repeats at a rate slower than a turn of the crank and the rate is different when on different chainwheels it's the chain. If what you are saying is that the jockey wheel is shifting sideways when the noise happens, or in time with it that would confirm the chain. Have someone pedal the cranks backward while you look from the cassette toward the chainwheels. Does the chain "snake" back and forth? If so that is the source of the noise. If it is binding in one spot, causing the deviation, flex it there to see if that helps. If not some chains will sound better after a while but I would consider that a defect and request a new chain. If the pulleys jump at a point on the chain it's a tight link, more than one I would consider a defective chain.

Note: For anyone not aware of why the timing above would be the chain - the chain will travel one complete revolution of the drive train in (number of chain links)/(chainwheel teeth). That will vary depending on what front chainwheel one is in but is anywhere from once every 2 to 5 crank revolutions.

The chain is not touching the front derailer. It is also not touching a crossmember of the rear derailer. The mechanical noise it makes corresponds to a wobble in the upper jockey wheel. As the clicky sound cycles, so does the jockey wheel wobble. They are perfectly in sync, regardless of what gear I'm in on how fast I pedal - it's the rate that the chain completes a revolution over the jockey wheel that dictates the cadence of the sound. The jockey wheel has some play in it, so I am supposing that the stiff chain is causing the wheel to wobble slightly and is the source of noise. I'm going to chase down the stiff spot in the chain, see if it feels different that the rest of the chain and gently see if it loosens up. That, and put some more miles on the bike.

Those wheels are molded from plastic. There' may be a mold line leftover that is making the noise. Also while the upper jockey wheel should be able to slide side to side the wheel should remain essentially in plane with very little or no tilt being possible. If it is able to tilt side to side a lot then there's something seriously wrong with it.

check for bent hanger and a properly routed chain through the rear derailleur. bike mechanics is not as easy as it sounds neither is internet diagnosis without any pictures or video

The upper pulley is supposed to travel straight sideways each way. There should be no tipping or wobbling. It sounds like you found the problem. It's easy to take the pulley out and examine it.

Did you put the chain on and put a new pin in? Did you loosen the link that is tight after putting it together?

Also that exact chain lube needs to be put on and ideally left over night, before using. That will make the chain a little quieter. When you first put it on it is too watery, it needs to set for a while.

I had this noisy problem when I tried to run a Mavic chain on my Shimano 10-speed rig. The chain was designed for use with Campy 10-speed and was just a tad too wide for Shimano, whose cassette cogwheels are slightly closer together. Too-wide chain.