New Chainset, terrible noise! (Video Included)

[Smokin Joe]

That's an indexing noise from the rear, not the front..

If that is the case, I wonder if the OP fitted the chain himself? It's very easy (And quite common - don't ask me how I know) to thread the chain over the outside of the guide on the rear derailleur instead of under it. The gears still shift but it makes a hell of a racket.

 

[raleighnut]

If that is the case, I wonder if the OP fitted the chain himself? It's very easy (And quite common - don't ask me how I know) to thread the chain over the outside of the guide on the rear derailleur instead of under it. The gears still shift but it makes a hell of a racket.

I did that once.

 

[nulleth]

I'd like to clear a few things up if I may.

I have four bikes working, and I've worked on all of them.
I've been repairing my own bikes for 15 years and have the basics down.
Indexing, FD alignment, and chain threading aren't the issues.

If I tell you, with a 100% accuracy that the noise is coming from the chain AND the teeth in front chainrings.

Here's what I've done...

• Had a studio mic against the bike in various positions. The noise is loudest at the front.
• Lifted the FD out the way completely.
• Lubed the chain.
• Indexed the gears several times to check.
• Bent, twisted, leaned (gently and by hand) the rear derailleur to check noise and alignment.

Please have confidence in what I'm telling you: It's not the FD, nor is it an indexing issue. I spent 3 hours last night indexing over and over to confirm.

 

[Smokin Joe]

Please have confidence in what I'm telling you: It's not the FD, nor is it an indexing issue. I spent 3 hours last night indexing over and over to confirm.

There's no need to take offence. Your OP didn't make your mechanical knowledge clear and we can only offer suggestions based on our own experiences.

 

[lpretro1]

Some Shimano cranksets are a little noisy when new and will bed in on riding - no idea why - it's just what we have found...

 

[raleighnut]

At the end of the video the chain hasn't shifted down to the inner cog, is it just running on the 'trim' setting at first and then not shifting down.

 

[Smokin Joe]

At the end of the video the chain hasn't shifted down to the inner cog, is it just running on the 'trim' setting at first and then not shifting down.

Well spotted.

 

[nulleth]

There's no need to take offence. Your OP didn't make your mechanical knowledge clear and we can only offer suggestions based on our own experiences.

Perfectly ok, I've never been good at conveying appreciation and respect across forums. I tend to just write like a robot.
I'm completely at the mercy of people's help here. And very much appreciate your time.

 

[screenman]

Did you use an alignment tool on the rear hanger?

 

[ColinJ]

I did that once.

So did I!

I was rushing out to meet someone and put a new chain on in a hurry. The bike made a right racket for the 10 miles it took me to work out what the problem was ...

 

[raleighnut]

So did I!

I was rushing out to meet someone and put a new chain on in a hurry. The bike made a right racket for the 10 miles it took me to work out what the problem was ...

Luckily mine never made it to the right way up.
I don't own a stand so mine sit upside down on 2 cushions on the floor til the fettling is done.

 

[User6179]

I did that once.

Me as well , still have the saw marks the chain made on the rear mech

 

[nulleth]

Could this be because the BB is slightly off center? As if the frame isn't faced properly, thus causing the chainrings to be slightly off angle with the frame, which in turn creates excess noise when the chain touches the teeth?

edit: Looking at the chainring during rotation I can't see any wobble or strange rotation, it looks perfectly centered.

 

[User6179]

Could this be because the BB is slightly off center? As if the frame isn't faced properly, thus causing the chainrings to be slightly off angle with the frame, which in turn creates excess noise when the chain touches the teeth?

edit: Looking at the chainring during rotation I can't see any wobble or strange rotation, it looks perfectly centered.

If the BB was off centre and the crank then the gap between the crank leg and the chain stays would be different on either side ?

 

[screenman]

Could you answer my question.