Help me diagnose this noise!

[vrotsos991]

In my past few rides I started to notice a knocking noise coming from my bike on hard sprints or standing uphill. I only hear the noise when I stand up and am putting a lot of force into the pedals.

Info that may help.

The pedals are Shimano and have 1700 miles on them.
The wheels are William System 30 with only 700 miles on them.
I took the chain off the crank and rotated the crank and it did not seem to hang up when i rotated it.
I loosened and re-tightened my skewers on my wheels to make sure they were nice and tight.
All drive train components are a sora tiagra mix with 1700 miles on them.
I checked to make sure the headset was tight by turning the wheel at 90 degreese and jerking the bike back and forth.
The noise does not make the noise at the same spot on each revolution of the crank

Anyone have some tips i could use to determine the cause.

 

[tonyzackery]

I suspect bottom bracket bearings.
See if you can isolate one side or the other.
Stand up and mash with one leg and soft pedal on the other, then try the other side.
If you have internal bearings (Octalink, Isis, square taper), you'll probably hear the noise regardless of which side you mash on. External bearing noise can be separated.

Not the BB bearings? Could be pedal bearings. Apply some grease at the spindle and see if that quiets them down.