I have a set of 2012 Cannondale Hollowgram SISL cranks on my 29er Hardtail. There's a creak that occurs in the downstroke of the drive side arm. Getting my (patient) wife to put her ear to things while I sit on the bike and put force on the crank arm, she can tell that the noise is coming from the pedal area and definitely not the BB. I've tried the following with no affect at all: 1) remove pedal, add teflon tape, tons of grease... reinstall (in case it was movement between the pedal and crank); 2) Swap pedal to my wife's eggbeater SL (in case it was the pedal body); 3) Swap shoes to my other pair (in case it was the cleats). I feel like the only remaining possibility is either the crank's pedal thread moving within the arm (they are hollow after all, and two sides bonded together) or the two bonded pieces of the arm moving at that outer edge of the arm. Anyone else experienced anything like this? I did a google search and it turned up nothing. Any help much appreciated!

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Enjoying my Funk

i had a similar problem and in the ent it turned out to be the xtralite chainring bolts.several attempts to take everything apart,grease,rebuild ended without a result(or creaking after 2 rides).using sram steel bolts now and it's quiet.
it may be worth to try molykote compound.it's a very thick kind of grease that sticks better to where you apply it and is very good for stopping creaking and rattling.

I'd feel less sure, but having had my wife put her ear next to various parts while I sat on the bike, and her being 100% sure that the noise originates from the pedal spindle / crank intersection... that seems pretty definitive. If there was movement between the pedal spindle and crank arm thread, I think 2 wraps of teflon tape plus grease ought to have at least _changed_ the noise a bit in tone or volume. But it didn't affect it at all.

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Enjoying my Funk

With all due respect for your wife, are you sure she can definitively determine that?

Ha, fair question She's pretty good with this sort of thing so I think so. I've also been able to make the noise with one foot clipped in and reaching down and the click feels very distinct with my finger at the pedal spindle and hardly noticeable at all with it at the BB. On these cranks the chainrings are direct mounted to the base of the DS arm, so if there was movement from BB or chainrings etc, I'd expect to feel the vibration strongest there.

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Enjoying my Funk

doubt it is the crank - the pedal threads are part of the inner crank half, and tensioning the spindle draws the two halves together. However, I would check the crank for cracking, as I cracked an old one (Si, not an SiSL). I would also check the spider lockring on the back of the crank, as well as the chain ring bolts. Finally, you can also check the BB spindle for wear on the bearing surface.

Re your wife's hearing, I doubt she can tell - the shock wave/sound propagates so quickly through the aluminum, she would not be able to differentiate one end of the crank from the other.

I once chased a noise in the BB for ages, only to figure out later that it was my front skewer.

With regards to the front skewer, etc... I feel like this isn't just a case of a noise when riding. I can sit on the bike, stationary, and create the noise. I can do it wearing flat sneakers or my bike shoes. I can only make the noise with the DS arm between 1 o'clock and 5 o'clock. I can't make the noise from the NDS arm in any position. And I can get my wife to hold her finger to various locations and ask her when she can feel the click, and she can't feel it when she touches the BB axle, or the chainrings... only when she touches the tip of the DS crank at the pedal spindle. I guess I'll take it over to the local cannondale dealer and see what they say.

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Enjoying my Funk

The only thing I can tell you is that the sound will travel thru the frame etc. The creak may sound like it is coming from a certain area such as your crank/pedal but maybe not where it is originating from. I have solved these issues in the past with process of elimination. I had a creak that I was so sure it was the cranks pulled them off regreased reinstalled still there. Checked my rear skewer was loose tightened fixed the problem. Second issue thought the cranks started creaking again checked skewers were tight then I check my seat was a little loose tightened it creak went away. Bottom line it could be anything on the bike not always the best to focus on one particular area.

I had a click with a Hollowgram set up in a CAAD9 and a CAAD10, both times it was the BB30 bearing outer race moving relative to the bottom bracket shell. In both cases I could induce the click by pressing on one spindle or the other with the bike stationary. The easy fix for me was to remove the crank arm and bearing shield and apply some Breakfree CLP at the shell/race interface; click gone. I did grease the shell when installing the bearings but after more than a year some surface corrosion from fretting was present on the bearing outer cage in a small spot.

This sounds like the pretty common BB30 creak. Reinstall the bearings using some light loctite and everything will be fine.