I've had a Trek 2000 since about 2005 and recently replaced the FD, RD, cassette, chain, brake/shift levers, and all the cable/housing. All new 5700 series 105 parts, except for the chain which is Ultegra. Years ago I replaced the triple 105 crank that came with the bike with an FSA Team Carbon double 53/39. My old cassette was 9spd and the new is 10spd.

With the new setup I get a grinding noise when pedaling under load in my small chainring. Not an ear-splitter, but definitely sounds wrong. Shift up to the 53 and the noise is gone. The 39t doesn't appear to be worn out, and wasn't making the noise before swapping out all the above parts. The sound isn't the chain rubbing on the FD cage. Chain is lubed, everything is new and clean, I'm sure I sized the chain correctly, and I've put about 50 miles on the setup to see if maybe the chain just needed to get to know the chainring but it still sounds the same.

What should I check? Is there anything else with chain alignment that I might've missed? Thanks!

a pic would help.is the wheel square in the dropouts so as to not allow the small cassette sprocket to be too close the the chainstay? the chain properly routed through the rear derailleur pulley's? new crank have the proper distance from the chainstay so the chain isn't making contact to the frame? "Road Double 43.5 mm Shimano spec, measured to the midpoint between the rings.
with typical 5 mm chainring spacing, this puts the inner at 41 mm, the outer at 46 mm."https://www.sheldonbrown.com/chainline.html

Is this happening on all/most of cogs of cass.? If smaller cogs mostly, could the chain be clipping the teeth on the big chainring at this extreme angle?

Is this a asymmetrical chain? correctly aligned?

How's shifting front and rear?

Several possibilities here. Chain way too long allowing the rear derailer to run out of capacity and run against itself?

My guess is a worn chainring.

Thanks for the response, I'm still working my way up to 10 posts before I can share pictures I guess...

It's definitely happening on most if not all of the cogs. I checked out the angle while on the stand and it doesn't look like the big ring could possibly touch the chain while I'm in the small ring.

Yes, and it's installed with the correct side facing out.

Shifting feels pretty great, maybe a little stiff on the FD but I think that's due to some less than ideal cable routing and lengths.

Nope, nowhere near running into itself.

I guess this could be it, and I was on the verge of just replacing it to check. It sure doesn't look bad compared to what others post when describing worn out chainrings, but maybe.

Is it while using any rear cog with the small chainring, or just the largest (innermost, slowest) cog?

Thanks for the reply.

Unfortunately, it all seems OK and should not be any of the issues that I had in mind. Your answers to all the other posters' question also seems to check out. Chainring may be the culprit.

Good luck.

No, nothing special. But you might be surprised how many people get it wrong! It's worth double-checking.

If it's only happening in the small ring and most/all of the cogs that rules out enough other possibilities that I still think it's a worn ring. Might be worth taking the FD completely off to make *sure* it's not rubbing.

Thanks all. I'll try removing the FD just to be sure and then pick up a new chainring if the noise is still there.

Check again if you don't know how it could be wrong.

Ha! I mean I’m looking at it compared to three other bikes in my garage and I’ve replaced chains before. I am however interested in how it could be done wrong.... It seems like you couldn’t reverse the orientation of the chain to the jockey wheels and have the chain even stay on both of them.

Open to specific things to look for though, not trying to be a jerk.

The tab on the DR cage between the upper and lower wheels.

Checked again, chain is on the correct side of the tab. Just to make sure, wouldn't that make an awful noise regardless of which chainring I was in?

is the new ultegra 10 speed chain installed in the correct direction-logos out? did you readjust the sis gear adjustment by shifting to the second smallest cog,turning cable adjuster till you hear clanging then back off till its silent?https://bike.shimano.com/en-US/techn...ls/hg-x11.html

This was it! I did not know about that process and after doing it the sound is gonzo! Thanks so much.