Zachanonymous

I'm suspecting it's the chain, seems too loose to not make sense. Although I can physically see it making contact with the front derailleur on my right foot's downstroke. I adjusted the rear barrel to match the rear cogs and that didn't seem to work. I put a few hundred miles on with it out of adjustment.

stills has a slight grinding noise on a full power left stroke.

bh85

See if this helps:

Front Derailleur Adjustment | Park Tool

Zachanonymous

I found another post from 6 years ago - He mentions dirty/worn symptoms causing a "grinding" (like changing gear noise) I guess I'll skip my ride tonight and buy a chain at walmart tomorrow, because I can wiggle it back and forth and side to side, pretty easily.

I hope thats it.

headasunder

You may find a new chain will skip over some of the rear cassette cogs, depending on how worn the old chain is, best to measure it first then make a call on whether you are up for both. Do you regularly clean and lube the drive chain? Rule of thumb is chain and cassette wear together and if the chain is changed in time you will not have any issues with chain skipping but if its left too late you have to change both together there are a zillion and 1 threads on this subject so do some research.

FBinNY 

Fist off, try and observe EXACTLY what's happening when you pedal under load. Often periodic or pulsed grinding is the result of the chainrings moving outward when the right crank is loaded.

If you see the movement, the cause could be frame flex at the BB, or a slightly loose BB, or even crank flex.

In any case the diagnostic process starts with observing what's happening, then looking for a possible cause.

BTW- some chainring movement under load is pretty normal, so if it's only slight, the answer might be to trim the FD outward a bit to accommodate it.

Zachanonymous

From my recollection the cassettes integrity looks fine.

BB I'm assuming is bottom bracket, seems good, I do get a lot of flex when I pedal. So I'm still working on adjusting my front derailleur.
And when you said the chainrings moving outwards on right crank, that's referring to the crank rings? or rear cassette rings?

FBinNY 

Sorry, most people here on BF are familiar with bike shorthand.

Yes, chainrings are the crank mounted sprockets, and the bottom bracket refers to the bearings the entire crank assembly turns on.

What I'm theorizing is that a you press the right pedal, the assembly is flexing so the bottom moves inward, and the top outward. So, what I suggest is that you look down through the front derailleur to watch whether the chain appears to be moving sideways with the FD cage as the frame of reference.

If you're uncomfortable looking down this way while riding, put the bike against a wall in a corner with the front wheel resting on the other wall. Get on the bike and hold yourself up by leaning on the wall as you press he right pedal trying to ride though the other wall (which hopefully doesn't collapse under the strain).