TreeUnit

I am experiencing loud, jarring click (sometimes a double click) once per pedal downstroke. It occurs on both the left and right pedal strokes in the 2 0'clock position. It is louder on higher gears

Here are the relevant components
BikesDirect "Bottecchia" Carbon Road Frame
Shimano 105 5600 Hollowtech Crankset
Shimano 105 5600 Hollowtech BB
Time Atac Steel Clipless pedals
Bontrager ProXlite Wheel/Hub, with Ultegra 10-speed Cassette
Ultegra Derailleur (not sure of ##)

A quick search found several past posts describing a similar "downstroke pop" problem, but the solutions found in those threads have all been accounted for in my case.

I have:
- tried another wheelset.
- switched rear derailleurs (from shimano 105 to current Ultegra Derailler)
- purchased a new chain of the same make (Sram 1031)
- switched Pedals (Time Atac to Sylvan Prime)
- purchased a new Bottom bracket of the same make.

- removed, cleaned, and amply regreased the bottom bracket, and screwed it on as tightly as my tool would allow me.
- removed, cleaned and regreased my crankset, tightening its screws as tightly as reasonably possible.
- switched back and forth between Sylvan and Time pedals several times, each time completely degreasing the parts before applying new grease and screwing them on as tightly as reasonably possible.

One thing that sorta worked was lubing the chain. I applied an ample amount of Pedro's Chainj lube, and the drivetrain was silent... for two blocks. Then the popping resumed.

Can anyone recommend other things to try?

Help Me Bike Mechanics... You're my only hope.

FBinNY 

OK the single most common cause of this is a loose crank arm on the spindle. Test by putting the cranks horizontal while coasting, then stand and shift weight down hard. Sit, gently reverse the cranks, and repeat. If you can feel the hard click doing this you have a loose crank.

However since chain lube has an effect, I suspect that you're feeling the chain going over the shift gates (cut or shaped teeth, twice on the outer ring) as it engages. Like a train passing over a switch, this can cause a click. You'll feel it more when using combinations where the chain feeds at an angle (outer with inner, or even outer with outermost) because the chain can move over a bit at the gate, then bite hard on the 1st full tooth.

As you see, better chain lube will help, and this often resolves with some break in.

If this is happening in the inner ring (which usually has no shift gates) while on the outer few rear sprockets, you might be feeling the chain snag on the pick-up pin on the inside face of the outer. This is common with the inner and outermost sprocket or two of 10s and 11s bikes, and the usual cure is to avoid the combination. If that's the issue and it bothers you, it can be improved by increasing chainring separation (but not always cured).

Anothe rpossibility is pedal movement in the arms. Usually you'll only feel it on one side, but the cure is to tighten the pedals, or remove and clean threads and faces then reinstall.

The last possibility is spindle movement in the BB, or BB cups or bearings not tight on the frame. This allows the crankset to rock left and right where the play is. If you can't verify other causes (even if not cure them) have someone check for spindle or BB play.

lennyk

Also make sure to remove and grease pedal threads
I had a creak even with very tight pedals, ony after greasing diditgo away

dsaul

Remove, clean and apply grease or carbon paste to your seatpost. Had the same noise the other day and the seatpost was the culprit.

cny-bikeman

Checking the Internet is fine but many people suggest "solutions" that make no sense. There is no noise that is exactly in sync with crank rotation that can be caused by either the chain itself, the derailleur, hub or anything outside of the crank/bb area. The simple application of logic is the best way to fix most problems on a bike. It's preferable to try tightening and cleaning all parts before putting money into new components, as clicks caused by a component being defective are very rare.